Cadillac HT-4100 / The Quest for 200K

Another Year Passed, Another 6 Thousand

2011-12-07T07:15:00.003-05:00

The DeVille is enjoying a well-deserved winter off in my garage. It just crossed the 90 thousand mile mark in September, and while it continues to run fine, signs of age are beginning to creep up.

In June, I took it to one of the best local upholstery shops and had the headliner replaced. The sag had pronounced to the point that the fabric was riding atop my head whenever I drove. Eventually I pinned it up, but that looked a little too white trash. So I bit the bullet - and what a difference! They matched the fabric to a tee, and it looks just like new.

This fall, after having the tires rotated, I noticed a popping sound coming from the front end whenever there was a marked body twist (such as going down a hill and turning at the bottom). A visit to my suspension guy revealed the problem; a broken stabilizer link. He also found a few more. The CV joint boots on the front axles are shot , and the struts front and rear are simply worn out from old age. I'm quite sure all are original equipment.

So, I'm looking at about $1600 to have them repair everything, or about $800 to do it myself. Crazy as it sounds, I'm thinking about just letting the shop do the job. After nearly three decades of gathering road salt, etc., old suspensions can be a pain in the a$$ to work on. Let them break bolts and studs and replace them. I'm getting too old and ornery for that kind of frustration.

Imagine that. The Cadillac may make it to 200k, but I'm going to be a grouchy old fart before it does...

Two Years Later - All is Still Well

2010-10-18T06:43:00.002-04:00

Does anybody read blogs anymore? Certainly not many people are keeping blogs like this. Everyone seems happy to turn over their entire private life to Facebook, in exchange for the benefit of intruding on everyone else's private life. Oh well, times change.

But vintage Cadillacs do not. It's near two years since my last post, and the 1987 DeVille continues its gentle journey to 200k. The odometer is creeping toward 85 right now, and all systems point to a long life. Since the water pump, mechanical issues have vanished. Not a rattle, stumble, squeak, or one single trouble code. An occasional rough idle this summer has been my only concern. With the cooler weather this fall, even that has cleared up.

My headliner has started to sag badly (very common to all 80s GM cars), so I will be taking the car into a local upholstery shop to have it redone. Later this year or early next, I plan to repaint the left rear door, which has gathered a bit of surface rust under the wide body trim.

Oh Oh

2008-10-14T15:26:00.003-04:00

Well, I knew from the start this was a gamble.

My latest oil analysis report from Blackstone Labs follows the oil change I did in September. They found coolant in the oil, and elevated wear levels in the bearing metals. Not good signs at all.

The Blackstone guys think it's probably an intake or head gasket. I'm still holding out hope (foolish, perhaps) that it's maybe just a fluke. My reasons are numerous. First, the level of actual coolant in the oil is pretty small - .24% - so if there is a leak it's not major...yet. Second, just before the last oil change I replaced the water pump, and it's possible some coolant slipped past the timing cover. Third, I let this oil go considerably longer before changing it: over 5 thousand miles and over 8 months.

To test my theory - and possibly risk my engine - I'm going to do another change at 2 thousand miles and have them analyze it again. If it shows similar or greater coolant intrusion, then I'll have to act.

However, after speaking with three experienced Cadillac technicians, I'm not sure what that course of action will be. All of them said that once you crack open a 4100, it's like Pandora's Box. You're almost assured to have leaks again in the future, perhaps immediately. Apparently the aluminum block, once released from the stabilizing pressure of the cast iron heads, warps out of shape. After that, it's near impossible to get a correct seal.

The service manager at my local Cadillac dealer suggested a unique approach. It seems Subaru has had very similar problems with a number of their engines; serious enough that they issued a recall. The first step Subaru directed was to try a new type of sealant in the cooling system. The SM told me they've had 80% success in sealing head gaskets with this stuff. It's made by Holts in England, and sold with a Subaru label and part number from dealers.

At $14 a bottle, I'm willing to take the gamble. Will report back on my success/failure.

Still Buffeting Along!

2008-07-17T16:04:00.002-04:00

Just a quick update: It's midsummer, and the Cadillac is running like a champ. No strange noises, no warning lights - it's really a remarkable piece of American engineering. Go ahead all you 4100 haters, sneer all you want. I'll just keep driving.

Yesterday, the old horse was shod with brand new shoes. My buddies down at Junior's Tires set me up with four Cooper Trendsetter touring tires. Cooper is one of the last American owned tire companies that still produces tires in this country (Dayton, Ohio to be specific), and I'm just old codger enough to believe that's important. Besides that, they're really nice tires, with a tread pattern that produces zero noise and a very smooth ride. It's also nice to not be embarrassed as I squeal around corners on the old front tires.

Still averaging 17 mpg city, and 24 highway. At $4+ a gallon, it's nice to still be able to drive a butter-soft luxury car.

Lack of Posts is Good News!

2008-04-06T10:31:00.005-04:00

I'm sure the 3 or 4 people who regularly read this blog are wondering if I've abandoned it. Not at all! Two things have conspired to keep me from posting regularly. First is a big video/audio project I've been working on. You can read more about that at my website.

The second reason is, the Cadillac has been running flawlessly. Pardon me while I knock on the wooden desk. Ever since the water pump near-miss in August last year, it's had no more problems. I changed the oil once, sticking with Amsoil but foregoing the Blackstone Labs analysis this time.

Of course, the Caddy sits around a lot in the winter. Not that I care that much about preserving it for the ages, it's just that our 2003 Olds Silhouette with GM's excellent traction control system is much safer to drive up here in the tundra (and we've had a helluva winter this year).

The odometer reads 61,642. So I've owned this car for 2.5 years, and have driven it less than 20 thousand miles, with a few minor (albeit somewhat expensive) issues. From the original purchase price of $2800, I've invested roughly another $1500 into parts and repairs. On balance, it's been a really good experience, and the things I've learned have been invaluable.

But at the rate I'm putting miles on this DeVille, it will take me another 21 years to get to my stated goal of 200K. I'll be 70 years old and the Cadillac will be 42. Think either one of us will make it?

The Water Pump Challenge - August 2007

2007-08-08T06:34:00.000-04:00

About a month ago, I noticed a buzzing noise coming from the serp belt area of the car. At first I suspected the tensioner pulley, as these commonly fail. Just to be sure though, I stopped at Auto Zone and picked up a cheap mechanic's stethescope. Probing around, it took only a minute to determine the noise was the water pump.

This was not welcome news - I've never had much luck with water pumps. On this sideways V-8, room to work on anything in the belt area is very tight. There is little margin for error. But, I pressed on regardless. The factory service manual gave a pretty benign description of the job, making it sound almost easy. A posting at cadillacowners.com brought several responses that further boosted my confidence. So with some time off work, I dove in.

First step in the process is to clear some room. This means moving all the components on the right fender, including the A.I.R. filter, the AC accumulator, the washer fluid bottle, the bracket, and the fender brace. To move the accumulator, disconnect the clamp on the radiator support to free up the flexible pipe, and swing the entire unit up and out of the way. I wired mine to a circular bracket mounted on the intake manifold, behind the air cleaner.

Once these items are cleared, access to the water pump is very good. The next step is to drain the coolant, then loosen the three bolts holding the pulley to the pump. Using a half inch breaker bar, put downforce on the belt tensioner atop the engine. This locks the pulley so the bolts can be broken loose. On the DeVille, you can actually remove all three bolts and the pulley before removing the pump.

The 4100's water pump is a thin, flimsy item about 14 inches long by 3 inches wide, by about 1/4 inch thick. It's held on by 18 different bolts and nuts. Three of the bolts are large hex heads, two are Torx head, and the remainder are smaller bolt and nut/stud combinations. To keep mine in sequence, I started with the top center large hex head bolt, then loosened all the perimeter bolts in a clockwise sequence. When I arrived back at the first hex bolt, I removed each one, then lined them up in order on my work bench. In the center of the pump is one Torx head bolt and two small hex bolts. Here again, all went smoothly until I got to the last Torx bolt. It was frozen tight as a drum. I did everything I could think of to break it loose: shot WD 40 on it, heated it, but it wouldn't budge.

Before long my worst fears came true,and I stripped out the head of that bolt. THE LAST DAMN BOLT!!! Next step was to try an EZ-out. Still would not budge. With no options left, I drilled the head off the bolt, and removed the old pump.

Now I had a quandry. Because this bolt is right next to the water jacket outlet, I couldn't simply ignore it or a leak would be certain. I rented a right angle close quarters drill, drilled it slightly bigger and tried a larger EZ-out. Absolutely would not move. I didn't push it too hard because the last thing I wanted to do was break off a tempered steel EZ-out and then have to drill THAT out.

Now it was really getting dicey. My only option was to try and drill the bolt to the same size as the original, then tap new threads into it. The tough part was, this had to be done with near perfect accuracy, and I would get one shot to do it. Adding to the difficulty was the access. A high-pressure AC line was directly in the way of my drill, so I had to have the local hardware custom cut a carbide drill bit to a length of about three inches. If I missed the angle, or was off by as little as 1/8th of an inch, it would mean pulling the engine. Finally, and most disconcerting, the water jacket in the engine block runs in and then up, directly behind where I would be drilling. Go too deep, and this project would get much more expensive very quickly.

Needless to say, I was sweating bullets as I started drilling. Carefully and slowly, I ran the drill in to a point I had marked on the bit as the deepest point I dared to go. So far so good. Next was tapping the new threads. This also went amazingly smooth. Finally, I test fit the bolt - AND IT THREADED RIGHT IN! Well, sort of - because I couldn't drill as deep as the factory bolt, there were not enough threads to allow it to tighten down. So I had to shorten the Torx bolt by 3/8ths of an inch to make it work. But it worked! What a rush that was. Of course, I wasn't out of the woods yet. I still had to get the new pump on and running without leaks.

It didn't take long to discover the reason GM used the Torx design here. The pulley and belt ride very close to the pump at this point on the engine, and no standard bolt design other than Torx would allow enough clearance. Because I had destroyed one of my Torx bolts, I needed a replacement. This isn't a basic hardware store bolt. So I called the local Cadillac parts department. The guy there is very helpful. Even though I was talking about a silly 7 dollar part, he took the time to make sure he had the right one. As it turned out he had to order it, but put a rush on it to get it to me the next day. I'll be back to do business with him again.

Last night I was able to put everything back together, and to my utter amazement this job has been a success. I started the car - no buzzing, no leaks. I may have a few more gray hairs than last week, but that's the price of admission to driving (and repairing) an elderly Cadillac.

All Systems Go

2007-06-09T08:37:00.000-04:00

June has arrived, and with the Cadillac, all systems are GO. For readers of this blog born after the peak of NASA and the Apollo missions, that means everything is working fine.

I finally got the EGR replaced, the throttle body injection settled down, and the A/C refrigerant recharged. The last item was the only one I didn't do myself. Initially I bought one of those recharge kits, but the system had an audible leak when I put in the R134; so I thought it best to take it back to John, the A/C tech who did the conversion back in 2006.

John found the leak in minutes - an O-ring at the Schraeder Valve on the low pressure line. He replaced that, charged it with R134, and viola! We're back in the cooool Cadillac business. Total bill for the service was $39.00. More than fair.

Of course with gas up to $3.50 a gallon, I'm not getting much chance to drive the Caddy any distances. It's pretty much limited to back and forth to work these days. We did take one 200 mile jaunt to Clare in May, and the Caddy produced 22 mpg. Coming up, we have a day trip to Mackinaw Island planned, plus a return to Clare, and I may take a day off to take mom out to lunch very soon. That should let the old girl stretch her legs some.

The picture isn't real. It's a Gimp generated fantasy image of what the Caddy would look like with limo tint windows and alloy wheels.

Kinda sharp!

The Trials of Working on an Old Cadillac

2007-04-28T20:22:00.000-04:00

Okay, so I was pretty overconfident of my diagnosis and repair of the EGR system. Then my wife an I took a 100 mile spin in the DeVille last week - and what should appear? The good old "Service Engine Soon" light, and the familiar E48 trouble code.

I still think the solenoid was not working, but apparently neither was the EGR valve. Rather than mess with it any further, I decided to just bite the bullet and drop the 68 bucks for a new AC/Delco valve.

That's where the challenge began.

Because of the way the EGR is placed on the manifold, it's nearly impossible to get to the mounting bolts with ordinary wrenches, and a challenge even for some expensive pretzel shaped tools. A plea for help at Cadillacowners.com brought me many helpful suggestions, the most promising of which was to loosen and lift the throttle body to give some clearance for an end wrench. So I did.

Because Cadillac uses custom bent steel fuel lines all the way from the tank, the first step was to break them loose at the throttle body. They join the TB with a two piece coupling; fairly standard design - or so I thought. The TB is then held to the manifold by three bolts, and a host of vacuum hoses had to be disconnected as well. Finally, I had it loose enough to raise about 5 inches, which gave ample room to get my wrench on the EGR. So far, so good.

About 1/2 hour later, the new EGR was in place, and the TBI was bolted back down. I started the car and everything seemed good, except a very strong raw fuel smell. It didn't take long to find that one of the fuel lines (there are two on this TBI system) was dripping pretty good. I fiddled with it for about another hour, but no amount of tightening could stem the flow.

I finally determined that the inner part of the coupling was leaking, right where it threads into the throttle body. So the next day I pulled it back apart to see if there were any cracks or signs of a broken O ring. Not finding any problems I elected to place an O ring in the space just to help it seat better.

My favorite local auto parts store matched the perfect O ring for me, and I purchased a new PCV valve at the same time. After getting them home on Thursday night, I put the thing back together again. On starting the engine I was glad to see the leak was gone, but now the engine was idling very high, around 2000 rpms.

I was very tired and frustrated at this point, but I went ahead and attempted to adjust the Throttle Position Sensor (TPS), using the instructions from the factory service manual. No luck; it still raced like crazy. So just before bed, I posted again on Cadillacowners to see if anyone had a suggestion.

The next morning, two people had offered ideas. Both responders pointed me toward a major vacuum leak of some kind, most likely the base gasket where the TBI meets the manifold. I remembered that while tightening the throttle body that one of the bolts had felt funny going in. I was quite sure the gasket was misaligned.

But again I was wrong. As it turned out, I must have been really tired the night before, because on Friday night I went back out to finish the job, and discovered I had never connected the big vaccum line that runs from the TBI to the power brake booster. I had a big vacuum leak all right - like the Grand Canyon of vacuum leaks.

I hooked it up properly, started the engine - and she idled like a purring kitten.
Since I had fooled with TPS the night before, I adjusted it back to factory spec and the 4100 just turned to silk. A short test drive proved all was well.

So in the end I learned three things:

1) Always check the basic stuff first. You'll usually find the problem there.
2) Never work on a Cadillac after a hard day at work and two Miller Lites.
3) I will buy a factory service manual for every car I own. They are worth their weight in gold.

EGR Repaired, new code appears

2007-03-28T11:41:00.000-04:00

The EGR problem from the last post is now fixed. On cadillacowners.com, a guy from Schaumburg, IL had an '85 Sedan DeVille that had blown the engine, so he was parting it out. I bought his EGR solenoid, plus a vacuum pump (which has been discontinued at GM parts) and an HVAC fan control module to keep as spares. About $500 worth of parts (dealer prices) for $50.00.

The parts arrived on Monday, and on Monday night I installed the solenoid. It works perfectly, producing a vacuum pulse to the EGR valve when the engine is at operating temp, and running above 2000 rpms. The old 4100 seems to run better, and I should see an increase in mileage right away.

But - there's another issue now. I cleared the trouble codes, took a short test drive, and rechecked the codes. This produced an F48 - Low Refrigerant Warning. Somewhere my A/C system has developed a leak and lost all the R134 over the winter. I'll run it back to the shop that did my conversion back in October of '05 and have them leak test and recharge it next week.

I've been thinking again lately about selling the Cadillac. For some reason, when I have car about three years, I start getting restless to have something else. I'm still hung up big time on the Oldsmobile Trofeo, but would be just as happy to find a really nice Olds Touring Sedan, Buick Reatta or Riviera from the '88-'89 era, or possibly even a Cadillac Allante.

Just dreaming right now, but you never know.

Code E48 - EGR System Fault

2007-03-10T13:29:00.000-05:00

Last fall, my "Service Engine Soon" light came on, so I ran the onboard diagnostic and came up with an E48, an EGR system fault.

After a little research at the forum board at cadillacowners.com, I found this is a very common problem with the 4.x series engines, used from 1985-1994. So, with a free Saturday today, I decided to diagnose and repair the condition.

Here is another example of why having a GM Factory Service manual for these older Cadillacs is indispensible. I was able to go down the trouble tree step by step, isolate the problem, and figure out what needs to be done to correct it.

I should say here that in my case, the code didn't cause any problems with the car. It still runs fine, although the mileage has slipped a bit.

First, a quick primer on the EGR system: Basically it's a part of the emissions control. The primary part is the EGR valve, a saucer shaped device mounted on the intake manifold behind the throttle body. This valve operates by vacuum, and when open it allows exhaust gases to be recirculated into the fuel in the intake manifold. This lowers the combustion temperature, which in turn causes the incoming fuel (and any un-burnt fuel in the exhaust) to be burned more efficiently. The valve only operates when the car reaches normal temperature, and then only after the engine exceeds 2000 rpm. The vacuum which opens and closes the valve is controlled by an EGR solenoid, which in turn takes it instructions from the onboard ECM computer.

To diagnose, start the car and let it reach operating temperature. Then remove the air cleaner, and disconnect the two-wire connector to the EGR solenoid. If the idle changes or the engine stalls, the problem is likely a vacuum leak or obstruction in the intake manifold passages.

In my case it did not change, so the next step was to jumper a test light across the connector pins to make sure power is being delivered to the connector. To test the car must be put into an ECM cycle mode. To do this, start the car, enter diagnostics, and turn on the cruise control switch on the dash. Turn the engine off, and turn the key back on within 2 seconds. Enter diagnostics again. When the FDC reads .7.0, press the HIGH button until the FDC reads .9.5. Then press down on the gas pedal and release to start the ECM cycle process. The FDC switches to .9.6, and the vacuum pump will cycle on and off. At this point the test light on the EGR connector should blink on and off every three seconds. If it doesn't, there's a short in the circuit or a blown fuse. The ECM cycle mode will stop automatically after 2 minutes, or you can simply turn off the key.

In my case it blinked normally so the circuit is okay. The next step was to check the EGR valve operation. Start the car, and place your fingers beneath the EGR valve until you can feel the diaphragm (careful, it gets hot in there). Reach across to the throttle body and raise the idle up to 2000 rpm. You can feel if the EGR valve is opening normally. In my case, it was not.

At this point I knew it was either the EGR valve or the solenoid. The next step in the manual is to hook a vacuum gauge to the hose leading to the EGR valve, to test the operation of the solenoid. It should read 3 pounds at idle, and 7 pounds at 2000 rpm. Since I don't have a vacuum gauge, I simply tested it with my finger. There was no discernable increase in vacuum when the engine revved. The solenoid was looking like the culprit.

To double check, I disconnected the constant vacuum hose from the other side of the solenoid and hooked it to the EGR valve directly. The engine stalled instantly, which told me the valve is working as it should. The solenoid was not opening to allow the proper vacuum to open the valve.

Now that I had a diagnosis, I needed a part. It turns out GM discontinued the solenoid, and so did AC/Delco. The aftermarket still offers it, but at Rock Auto the price is $144, and they don't have it in stock. Bummer.

My next step is to try the junkyard. My old friends at Gene's still have both the '86 and the '88 I've robbed parts from before, so Monday I'll buzz out and pull one. Using electrical/mechanical part from a junkyard is a gamble, but if I stumble upon a good one for $10 - it's worth a try.

At Rest

2007-01-22T06:49:00.000-05:00

Wow, it's been three months since a posting! I've been busy with other projects, and the Cadillac hasn't gotten much attention. Right now, it's sitting quietly in the garage awaiting spring. It hasn't been driven much since Christmas as winter has finally settled in here in Northern Michigan. I will drive it a couple of times this winter just to keep the battery charged, but mostly we're driving the 2003 Olds Silhouette these days. It has heated seats and traction control - gotta love that.

Just before I put the Caddy into hibernation, a trouble code popped up. The very common E48, which is an EGR issue. The most likely culprit is carbon buildup in the manifold passage serving the EGR valve. The good news is that the diagnosis of this problem is pretty easy, and the fix - even if it requires new parts - is relatively cheap. I've also noticed the mileage slipping a bit, down to about 13 around town and 21 on the highway, but that's likely a result of whatever is wrong with the EGR system.

Other than that, not much to report. The Cadillac still looks, runs, and floats down the road like a new one, and I'm loving every minute of it.

The results are in - Amsoil is doing the job

2006-10-26T09:24:00.000-04:00

Well, it appears the research has paid off. My choice to go with Amsoil in the HT-4100 was not without its critics. In fact, most of the respondents at cadillacowners.com told me at best I was wasting my money, and at worst I could be prematurely destroying my engine.

But the proof is in the results, and here they are:

It may be kind of hard to read this form, but the general theme of it is this: Since I started using Amsoil 10W-30 synthetic 18 months ago, the wear rate inside my engine has been reduced dramatically. In the first report, the lab tech told me that "The GM 4.1 is not the best wearing engine, but yours is wearing better than most." In this report, the comment says, "...you're doing something right."

That sodium level that was a matter of concern in the initial report (high sodium could indicate coolant contamination) took a nice drop on the latest test, as did all the trace metals and contaminant levels. The TBN of my sample was just a fraction lower than virgin oil of the same brand/weight, so it would have been suitable to run in the car for some time longer. Blackstone has recommended a 4200 drain interval for the next change.

Finally, when you compare the significant wear metals of my engine vs. the universal averages, the wear rate of my 4100 is about 67% lower. The conclusion? Amsoil is doing exactly as the science predicted it would - protecting my engine extremely well. Suddenly, 200 thousand miles doesn't seem like an unreasonable goal.

The Once A Year HT4100 Survival Kit

2006-10-22T09:42:00.000-04:00

As I've written here before, the most critical element to preserving an HT-4100 equipped Cadillac is the careful and regular attention to the engine fluids, particularly coolant.

At right is what I like to call the HT-4100 Survival Kit. It consists of five quarts of Amsoil 10W-30, an Amsoil Absolute Efficiency oil filter, two gallons of undiluted anti-freeze/coolant, three gallons of distilled water, and a blister-pack of six of the GM Sealer Conditioner tablets. This year I took the extra measure of changing out the thermostat and the lower radiator hose.

Fall just seems to be the best time for me to accomplish tasks like this, so on October 14, the DeVille went up on jackstands in my garage. The first step in the process was to remove the thermostat, which on this car is particularly easy. It's one of the few places on this car that's handy to get to; and it's well-designed to boot. Just two bolts, pop the old 'stat, and replace it with the new one. The beauty of the design is there is no fiber gasket, simply a grooved O-ring that fits around the thermostat. It sits inside a machined shelf, with just enough of the O-ring above to seal perfectly.

Slightly more challenging was the removal of the lower hose. Cadillac thoughtfully drilled a hole in the bottom of the radiator support panel which allows access to the hose clamp. It works providing the last mechanic who installed a hose was thoughtful enough to position the clamp properly. I did not luck out on the latter. The clamp screw was pushed just high enough that a screwdriver could not get a bite on it, so I had to remove the lower clamp with a tiny brass wrench that came with some part I bought years ago. You know, one of those things you hang on to just because 'I might need it someday." This little wrench was also used to reach the top clamp, which was almost hidden by the array of hoses and pumps on the component side of the sideways V-8.

Removing the lower radiator hose proved to be an exceptional way of draining the radiator. While the drain petcock trickles like an old man with a bad prostate, the hose method gushes the old coolant out in a matter of seconds. This picture is what the coolant from a 4.X series Cadillac engine should look like. The supplement sealer tablets change it from that candy green to a chocolate brown color. I was pleasantly surprised at how clean the thermostat and hose areas were, as well as the coolant itself. No rust or gunk buildup whatsoever. That tells me the internal passages of the rad and engine are probably just as clean, and the old engine is still in pretty good shape.

Next step in the process is to refill the radiator with distilled water, then start the engine and run it up to operating temperature. It's also important to run the heater at full blast during this process to flush out the heater core. Of course the engine must be allowed to cool off before opening the radiator cap again, so I used that 45 minutes to lube the chassis and then change the oil.

Just after pulling the plug on the oil pan, I captured a sample of the Amsoil to send off for analysis. This time around the oil has been in the car for six months and 3600 miles, or about 100 miles more than the last change. I'm really hoping for a good report from the folks at Blackstone Laboratories.

Once the oil change and lube was done, it was time to return to the coolant. I removed the lower hose again and drained off the flush water, then refilled the radiator with a 50/50 mix of Peak Full Force coolant. About halfway through the refill process, the GM sealer tabs were crushed into a powder and poured into the radiator.

When the job was done, it was time for a short drive to let the coolant mix well, and the sealer to find any spots where it needed to work. A 15 minute spin around town did the trick, and the Caddy is good for another six months on the oil, and a year on the coolant.

Fall Fixes - Repairing the power Seat and Antenna

2006-10-08T15:16:00.000-04:00

During the summer, the front tilt motor on the driver's seat started making a grinding noise, like a gear had stripped, and it would not move into a lower position. It still went up, but not down. Since I drive the car most of the time, this wasn't a serious issue, but would cause problems if my wife had to use the Cadillac - she's a foot shorter than me!

Also, my power antenna has never worked. It was stuck in the up position. These two items are all that kept my DeVille from being 100%, so this October I decided to attempt repairs on both.

The previous post was all about my foray into the junkyard, and this post is about the results of that trip. I pulled a power seat cradle off the only '87 Sedan DeVille at the yard, hoping that it would be functional. Removing the seat from the Cadillac is simple, providing you have power to the seat. First step is to pull the trim caps (1 screw on each) where the seat bolts to the floor. This is best done by running the seat all the way forward to get to the rear caps, then all the way back to get to the front caps. Then pull the six 13mm bolts holding the seat to the floor studs, unplug the power connector, and remove the seat.

I should mention that later work becomes much easier if you run the front and rear tilts to their highest point. Four 13mm bolts hold the power cradle to the seat assembly.

The junkyard part I rescued had a broken adjuster plate, so I had to disassemble the tracks from the motor assembly and build one unit out of two. It's really easy to do this. The drives connected through plastic coated flexible square cables that snap onto both ends with simple connectors, and the entire motor assembly is held with one nut. You have to twist the square cables a bit to get them to slide into place, but a little patience gets everything together.

Since the two tracks I built up were not aligned to each other, I had to remove the seat a second time. The alignment was accomplished by eyeing the position of the replacement track, removing the drive cables from it, then plugging in the remaining track and settting it as close as possible. It worked like a charm. The seat is now back in the car, and working perfectly. Cost - $85.00 for the junkyard seat track.

My second project was to repair the power antenna. My factory service manual told me that if the antenna moved up and down a few inches, the likely culprit was a broken cable inside the mast. At the junkyard I pulled an antenna from the same '87 DeVille, and was pleased to see that it looked as though it had been replaced at some time in that car's life.

Removing the power antenna is easy, although space is at a minimum. The first step is to loosen the fender access panel on the right side. First, turn the wheel all the way to the right, then remove the four screws and two or three snap retainers that hold the plastic fenderwell panel in place. The panel can be folded up and over the tire, exposing the antenna motor.

There is a plate with two bolts holding the antenna to the fender at the bottom. The factory service manual says to disconnect the antenna and power cable under the dash and remove them with the antenna, but because of the difficulty of routing those cables back in, I elected to simply snip the power wires under the fender and remove the two screws that hold the antenna cable to the mast assembly.

The final step to getting the antenna out is to remove the screw at the top of the fender under the hood. I made the mistake of thinking the two Torx head bolts were what held the antenna into place, but these are the support plate bolts for the hood hinge. It's just that one single Phillips screw adjacent to the the hole where the mast emerges from the fender. From there, it's just twist and turn and wiggle until the antenna assembly drops out the bottom.

After testing my junkyard antenna and finding the motor dead, I decided again to attempt building one unit from two. The cases are held together with five metal clips, three eyelet fasteners (that must be drilled out to remove), and the water tight sealant. Disassembling my antenna case proved the manual was correct, the white plastic cable that runs the length of the antenna, and spools on the gear at the bottom, was broken.

Luck was not on my side though. After taking the junkyard case apart, I discovered that it also had a broken drive cable. So I simply sealed up my old antenna and put it back in. The radio works fine with it - this was more of a cosmetic/perfectionist repair. I'll keep my eyes open in case I run across a known good antenna, but make do with what I have in the meantime.

The last Cadillac project for the fall is the change the oil, replace the lower radiator hose, and flush the coolant. Hopefully I can get that done next Saturday morning.

Junkyard Prowling

2006-09-26T14:23:00.000-04:00

There is no doubt about it. I love prowling junkyards. This morning I went out to my favorite local boneyard seeking some parts for the DeVille. Nothing really critical, it's just that I decided to fix the power seat and antenna before the snow starts flying. It's much of a pleasure to pull parts on a sunny September day than to attempt the same when there's three feet of snow on the ground.

The yard has two DeVilles in my vintage range; one an '86, the other an '87. They had a white '88 last year, but I noticed it was gone this fall - probably off to the crusher. The blue '87 nearest the camera is the primary parts donor for me. The '86 next to it is a really loaded example, including the factory sunroof option, twilight dimmer and sentinel. Interestingly, both cars have almost identical mileage: 179,000. They both still have the factory 4100 engines, too. From appearances, they probably ran when they came here, but the transmissions went bad.

I pulled the parts I wanted in about an hour (see the next post for details on the repairs), then took the digital camera around the yard to see what I could see. I'd estimate this yard to be around 10 acres, with probably 2 thousand cars. As I've posted before, they have a great system. When a newer car arrives they strip it of all saleable parts and those go into a warehouse. The older stuff is placed on 3 foot high iron posts, which makes it very easy to get to almost everything you might need. They give you a discount if you pull the parts yourself.

One of the first unique pieces I came across was this 1988 Olds Touring Sedan. It's almost complete, including the interior with those great infinitely adjustable buckets. The odometer reads 257 thousand miles! Short a little surface rust, it looked in pretty fair condition. One of the yard guys told me they drove it in to the yard - the only thing wrong with it was the trans was missing reverse gear.

Seeing this Touring really broke my heart. I've decided this is now #2 on my list of 'want' cars. The Trofeo I thought I wanted has dropped to third. The Cadillac is running so damn nice it's hard to even think about selling it or moving on to something else, but when I do think about it - my list is:
1) 1988-89 Buick Reatta
2) 1987-91 Olds Touring Sedan
2) 1988-89 Olds Trofeo

The other most interesting find was this 19(95-96?) Cadillac super-stretch limo. It's hard to believe how badly rusted this car is for only being 10 years old - but notice that the rust is confined to the area where the stretch plug was inserted. The original Cadillac body panels are rust free. This car was stripped completely of it's interior, other than the front seat. The blacked out side glass was pretty much intact, and it still had the builder's plaque on the trunklid.

It had been built by Master Coachbuilder Chicago Armor and Limousine Company, but something tells me this image probably won't show up in their next sales brochure!

It's funny really, when you consider what it costs to have a limo built, and the fact that they are the ultimate luxury car, you would think they would get racehorse car all their lives, but I see lots of beat up, rusted out limos running around. I must admit though, this is the first one I've ever seen in a junkyard.

Flawless Summer

2006-08-27T11:27:00.000-04:00

One weekend before Labor Day, and it's been a flawless summer of driving for the '87 Sedan Deville. Here's the report: The Cadillac now has 52,400 miles, or about 7 thousand miles accumulated since I purchased it in May of 2005. Since replacing the alternator last November, it's been running trouble free. The only repairs needed since then have been preventive maintenance and cosmetic. It's been driven daily as our primary transport, mostly back and forth to work and on weekends, and hasn't even had a hiccup. The A/C works perfectly, and the mileage average is 16.4 in town, 24.5 on the highway.

In October, I'll change the oil again and send off a sample to Blackstone Labs for analysis. This will be the confirmation test of Amsoil, to see if it lives up to my expectations. Also due up is a drain-flush-refill of anti freeze, which in my opinion is the single most important maintenance item to preserve an aluminum block Cadillac engine for the long term.

There are two other issues that will be addressed this winter, while the Cadillac is comfortably tucked away from the bad weather. First is removal of the front seat to repair the tilt motor, which has stopped working on the forward side of the seat. The motor still runs, but it just spins like the gear is disengaged.

The second project will be the removal of the power antenna. The GM factory service manual gives pretty detailed instructions on how to remove and repair the antennas. Here again, the motor runs fine, but the cable which pushes and pulls the antenna up and down seems to have broken or become detached.

Almost 100%

2006-07-09T16:51:00.000-04:00

Today there were thunderstorms predicted, so rather than do fun summer stuff, I decided to spend a little time fixing some things on the Deville that had been waiting. The list went like this:

1) Replace the window/seat switch control trim on the passenger door.

2) Replace the bad hubcap center on the left front.

3) Test the switches to figure out what's wrong with the cruise.

The first two jobs went really smooth. Replacing the switch trim was really simple, thanks in part to a fellow poster at cadillacforums.com who sent me a step by step guide to removing the door trim, including photos!

The old trim piece was really beat. Here's a picture of it after it was removed:

Getting this switch trim out is quite simple. On the passenger side, there is a notch in the front of the trim. Beneath that is a spring clip that holds the trim to the door panel. Just stick a flat screwdriver in and depress the clip, then pry up to remove. The rear of the trim is held by a simple plate that slides over the door panel on the horizontal. The whole switch unit comes out as an assembly. The trim is held on by three screws at the bottom. Here's what it looks like taken apart:

The replacement trim I salvaged from an '86 Deville at the junkyard last fall. The few chips it had were easily touched up with a laundry marker. The only tricky part was that the flat retainer plate was missing from my new part, so I had to transfer the old one. Unfortunately, it's held on by something akin a rivet, so I had to drill the old plate off, then carefully drill two small screw holes in the replacement trim piece. After threading in a couple of small sheet metal screws, it went together just like the factory unit. I reassembled the switch plate and reversed the process to install. The result looks just like new!

The hubcap thing wasn't really all that critical, just annoying. The red-crest center on my left front wire wheel cap was quite loose, and at low speed it sounds like there is gravel in the hubcap. I picked up three old caps from a guy in Midland when we went to the car show in June, and today cleaned up and swapped on one of those caps with a good, tight center. The sound is gone.

Next on the list was testing the switches on the cruise control. As noted earlier in this blog, the cruise has never worked properly on the Deville since I've owned it. Engaging the cruise put it into a constant acceleration mode, almost like flooring the gas pedal. It could be quite unnerving, as it felt like the car was going to run away.

The engineers at Cadillac really did the onboard diagnostics right. You can test all kinds of systems on the car just by manipulating the correct switch sequence on the climate control panel. This is why I encourage anyone with even modest mechanical abilities (like me) to get a copy of the GM factory service manual. Inside is a wealth of diagnostic testing material, and all the 'trouble trees' that take you step by step through the process of determining the source of problems.

In this case, the cruise control switch test can be done after running through the normal diagnostic routine. That is "Off" and "Warmer" hit simultaneously with the key on. The Fuel Data Center shows all intermittent and hard trouble codes, then reads .7.0 when it finishes the test. To test the cruise switches, you do the diagnostic routine with the engine running. From .7.0, the brake pedal is depressed and released. The FDC then reads E.7.1. From here on, all switch tests must be done in order within 10 seconds intervals, or the computer will interpret the lack of input as a faulty switch. Here's the order of tests:

1) Depress the brake pedal again to test the cruise release switch.
2) FDC switches to E.7.2 Push throttle down about 1/4th of the way and release slowly to test the throttle switch. FDC switches to E.7.4 (E.7.3 is skipped)
3) FDC switches to E.7.4 (E.7.3 is skipped) Apply brake and shift from Park to Reverse to Neutral. This tests the park neutral switch.
4) FDC now reads E.7.5 Set cruise master switch on dash to ON position, then OFF to test that switch.
5) FDC now reads E.7.6 Turn cruise master switch ON, then depress set/coast button on turn signal lever.
6) FDC now reads E.7.7 Cruise master switch ON, depress and release resume/accel switch on turn signal lever.
7) FDC now reads E.7.8 Turn wheel all the way to the right or left, then back to center. This tests the power steering pressure switch.
8) FDC will read E.0.0, then go back to the standby .7.0

After completing these tests, the FDC will re-display any switch number that did not test properly.

In my case there were no switch errors, so I moved on to cycling the cruise vacuum valve and the cruise power solenoid. To do this, you shut the engine down, then turn the key back to the ON position within 2 seconds. You then re-enter the diagnostic mode. When .7.0 is displayed again, you press the HI button until the display reads E.9.5 From here, depress the gas pedal and release it. The display should switch to E.9.6 Turn the cruise master switch on the dash ON
and the power solenoid will start cycling rapidly. The cruise vacuum valve will cycle on and off every 3 seconds. Again, my system came up normal.

The next set of tests gets kind of involved; checking vacuum hoses and electrical connections, so I thought it was a good time to break for lunch. On the way to the store, on a whim, I tested the cruise control. Lo and behold - it WORKED PERFECTLY! I just about danced in the driver's seat!! I can only assume that running the switch test and cycling the vacuum components corrected whatever condition was causing the original problem. In any case, I'll take the easy fix any day!

So the Cadillac is near 100%. Everything is working as it should, with only a couple very minor exceptions: the power antenna - which I have no intention of fixing - and the recently developed front-tilt motor on the driver's seat. It sounds like there may be a stripped gear. But since the seat is set for me, I'm not too worried about that either.

Man it's nice when the Cadillac gods smile at me.

Road Trip #2 - Mackinac

2006-06-26T10:24:00.000-04:00

For about the past 8 years, my wife and I have enjoyed spending Father's Day weekend at Mackinac Island, which is the final weekend of their two-week long Lilac Festival. We always stay at the same place, and do the same things, but it's alway's a blast. Mackinac is a very cool place.

This also afforded a great opportunity to get the Cadillac out on the road again, so on Saturday, June 17th, we pointed the crest north. It was a great ride up, about 125 miles from our house to Mackinaw City, where I entrusted the Cad to a young valet at the Shepler Island Ferry Company (after checking the mileage first, of course). The old girl performed smoothly and without a single hiccup on this second long trip of the summer - and oh how nice it was to have the air conditioning working - as Saturday was blistering hot. We rode along in total 72 degree comfort, while outside the pavement broiled at 90+ degrees.

Our four days on Mackinac were blissfully quiet and peaceful. There are no motorized vehicles allowed on the island, so all transportation is by horse drawn carriage, bicycle, or your feet. We hiked a lot, and on Sunday, rode bikes around the island early in the day. On the southeast side, the most famous of the island's limestone formations rises in dramatic fashion. Arch Rock was originally carved out by wave action when the lake levels were much higher, forming a perfect stone arch. It's looked like this for hundreds of years, but erosion is still taking its toll, and the State Parks geologists expect it will probably collapse in the next 80 years.

A few hours after this photo was taken, it dumped rain. Unfortunately, the height of the storm was right in the middle of the Grand Parade, but it was still enjoyable to watch. About 20 minutes after the parade ended, the sun came out, and we enjoyed a concert in the park performed by the Scottville Clown Band. This all-volunteer band is the funniest, and by far the best marching band I have ever seen. They are so powerful and loud, they make most big time college bands pale by comparison.

On Tuesday afternoon, it was time to head back to the real world. After four days on the island, coming back to the mainland is an assault on the senses. You so quickly grow unaccustomed to traffic noise and the smell of exhaust, it requires re-adjustment period. However, driving a Cadillac, even a 19 year old one, takes the edge off pretty nicely.

We arrived at the dock in Mackinaw City, and the old girl was waiting for us, having been delivered by the valet just as promised. Our trip south was uneventful, and once again, the Deville drove smoothly and flawlessly all the way home. Running on Shell V-Power premium, we averaged 24.6 mpg, using the air about 3/4ths of the time. The odometer now reads just over 51 thousand miles.

Early Summer Road Trip - Caddy Rolls Up 50K

2006-06-06T09:21:00.000-04:00

On June 3, my lovely wife and I made one of our many annual summer day trips; this one to Midland for the first of three antique festivals - that also happens to include a pretty good car show and swap meet.

It was a perfect chance to get the Cadillac out on the road again. The majority of the driving time the old girl gets is just around town, and she needed a good open road run to clean out the carbon. Midland is about 250 miles round trip, 2/3rds of which is two lane highways and the rest freeway.

The weather was ideal, sunny and in the mid 70s, very low humidity. There was a slight chance of rain, and in fact we heard a couple of thunderclaps shortly after arriving, but we never felt a raindrop until the ride home. The car show was fair - not as many participants as I've seen in years past, but there were some very nice Cadillacs in the show, including the two 1959 models pictured here. Above is a bright red convertible, and below is a '59 two-door hardtop. Both were in exceptional shape, and represent the peak (literally) of the tailfin era of the late 1950s design.

At the swap meet, I found a trio of wire wheel hubcaps for an '87 Deville, and offered the seller 10 bucks for the bunch. He agreed, so I bagged them up and went on my way. The crest centers on my current hubcaps have loosened over the years, and sometimes it sounds like I have stones in the hubcaps at low speed.

There is also a dealer who sets up at every Midland show who sells all kinds of automotive literature. Shop manuals, showroom brochures, owner's manuals, you name it. I just love browsing through this stuff, and always seem to find a treasure. This year I picked up a dealer brochure for the 1989 Buick lineup. It's literally like a catalog - almost 70 pages, and covers all the Buick models pretty thoroughly. My main reason for buying it was because of my recent interest in the Reatta/Riviera models from the 88-89 era. Like the Trofeo, they have a touch screen computer on the dash. It's not as colorful or elaborate as the Oldsmobile VIC, but pretty cool just the same.

Mid afternoon, we pointed the Cadillac northwest, and headed home. We did make a couple of side stops in Clare, first at Jay's Sporting Goods, then to a little gift store my wife likes, and finally to my favorite mid-Michigan spot, the Doherty Hotel for lunch. While we ate, it simply poured down rain, but stopped just before we were ready to depart.

The night before this road trip, the Cadillac passed the 50 thousand mile threshold. It looks, runs, rides, and feels just like a new car, even though it's nearly 20 years old. During this 266 mile round trip weekend, the HT 4100 pulled 24.5 miles per gallon, even though we were USING the air about 75% of the time.

Yes, it has a couple of issues yet to be resolved, but overall, this is one fine Cadillac that I'm proud to own. Having said that, I'm contemplating the possiblity of buying either a late 80s-early 90's Olds Trofeo (there's a beauty on eBay right now), a Riviera, or a Buick Reatta. I like those styles better, they have more gadgets and toys to play with, and they're both powered by the highly reliable (and much easier to work on) 3800 engine. This of course would require selling the Cadillac. That would be hard for me to do, but my garage, my budget, and my wife just won't accomodate the idea of three cars.

Oil Analysis Results

2006-05-25T09:48:00.000-04:00

I was right!

Well, sort of...

The results are back on my first lab test sampling of Amsoil used in the Cadillac. To recap, I was searching for the best possible oil to help in preserving the HT-4100 engine. Many suggestions came my way from fellow Cadillac owners, but I dug a little deeper, read a mountain of research, and came to the conclusion that Amsoil synthetic motor oil might be the right choice.

At first, I was willing to trust Amsoil's claim of radically extended drain intervals. The particular grade of oil I used (5W-30 ASM) is supposed to provide above average protection to 25 thousand miles or 1 year of service. I never intended to let the oil go 25k, but a year didn't seem so crazy.

Well, a lifetime of admonitions from my late father (the best auto mechanic I ever met) bothered my conscience, so at 3500 miles and 8 months of service, I changed oil. For the summer I switched to the Turbo Formula 10W-30 Amsoil.

I took a drain sample of the old oil and shipped it off to the good folks at Blackstone Laboratories of Ft. Wayne, Indiana. I just happened to pick them off the internet - what a fortunate choice that was! Blackstone provides a complete chemical, metals, and mineral content analysis of motor oil for just 20 dollars, and they'll even ship you the sample kit free of charge! For an additional 10 bucks, they'll do a deeper study of all the additives in the brand of oil you use, to tell you how they've held up. The analysis report is sent via e-mail (PDF) as well as a snail mail hard copy. The whole process from shipping it off to receiving the results takes about 4 business days.

It may sound a little wierd to get excited about an oil analysis report, but when mine arrived on Tuesday, I dove into it like a best selling book. It's only one page, but it tells a detailed story about what's going on inside the engine. In my case, the 4100 is slightly better than average in trace metals, which means wear inside the engine is less than normal. The additive chemicals in Amsoil retained their quality, although the sustained viscosity number was slightly higher than it should be.

The only matter of concern was an elevated level of sodium in the oil. The average is 13 ppm, and my sample contained 25 ppm. Some oils use sodium as an additive, but Amsoil does not. While this could indicate some minor coolant contamination, the number is so small it's not enough to worry about yet. I called the lab tech to inquire if this contamination could have been induced by my working on the lower coolant hose at the same time I did the oil sample. He said, "Possible, but not likely." The more likely culprit is that it's simply residue from when the intake gaskets failed a few years ago.

My primary question of the lab was: Is the Amsoil still good for continued use? By way of answer, I will quote directly what the report says:

"It's not really whether the oil is suited for extended use, but whether your engine is suited to it. The engines that have the best luck with long intervals are those that make little metal. The GM 4.1L is not the best-wearing engine ever made, though yours is better than most."

Also during my conversation with the lab tech, I asked his opinion of Amsoil, and he said "It's a good product. I wouldn't put too much stock in their extended drain interval marketing. We have done analysis that demonstrate some grades can lose viscosity faster than comparable synthetics. But in terms of protection, it's among the better oils out there."

All in all, the analysis pretty much confirms what I've believed all along about Amsoil. The GM 4100 is not the best wearing engine, but after using Amsoil, the wear levels in my engine are better than most. Because of the sodium content, I plan to change it again at 3500 hundred miles and have a sample analyzed by Blackstone. Hopefully the sodium will return to normal in the next test, but I'm willing to bet the wear levels stay the same, or even drop somewhat. If that's the case, I may go ahead and extend the change interval to 5 or 6 thousand miles in 2007.

Two Down, One to Go

2006-05-18T13:54:00.000-04:00

This week was cold and rainy, just like last week. Since I can't do much yard work, it presented the perfect opportunity to get some of the maintenance issues done on the Deville. My Amsoil order arrived on Tuesday, so after work, up went the car on jack stands, and into it I dove.

The first step was to drain the coolant and remove the 2-inch piece of rotten hose that joined the coolant distribution tube at the bottom of the engine. This really seems a strange design to me - why run a steel coolant tube beneath the engine, to a place the average driver would never look, and where it will be relentlessly hammered by road debris, salt, and crud? Just one of those compromises Cadillac had to make to get the 4100 in there sideways I guess...

Before I started, I inspected the area closely and discovered that most of the 'rust' was actually just swollen and flaking enamel paint that Cadillac had put on at the factory. There seemed to be plenty of good metal left underneath it. Here's how it looked at the start:

After cutting away the hose and breaking off most of the paint flakes, it didn't look nearly so bad, but I was glad to get it repaired anyway. The front section of the tube is joined directly into the engine, so I didn't mess with that. The rear section is connected to two heater hoses at the top of the engine, and held by two brackets, one midway up the block, the other near the curve at the bottom. Both are a bitch to get to, but I was able to loosen the upper bracket enough to twist the tube for better access.

Back on the floor, I packed both open ends of the tubes with shop rags, then scraped away the rest of the flaked paint and rust with a stiff wire brush. Then came the Dremel tool with a soft wire brush to skim off the rest of the surface rust, and last a light sanding to smooth them out. Finally, three heavy coats of Rustoleum paint made them look almost new again:

A great suggestion came to me from two users of the Cadillac.com forums - replace the short hose with a longer piece of heavy duty hose. This serves to pass the coolant, plus protect the metal tube from further abuse from road crud.

I went to my favorite hometown auto parts store, and asked for the best heater hose they had. They suggested an engineered hose from Gates, which is super heavy and will stand up to lots of heat and abuse. It was $7.00 a foot, but to prevent me from having to do this job twice, that's a bargain!

I coated both ends of the metal tube with WD40, then slid a 5 inch section of the heavy hose as far on the rear section as it would go. After a little persuasion,

I was able to force it onto the front section, then slide it forward to cover almost all of the exposed metal tubing. To finish the project, I used 4 clamps. The two on the inside prevent coolant from leaking out, the two on the outside prevent moisture and salt from getting in. It's a sealed, permanant repair that I should never have to worry about again.

Feeling pretty proud of myself, I moved on to changing the oil and filter. If you've read this blog from the beginning you're probably thinking, "Hey! What happened to all that unshakable faith in Amsoil being able to go a year without changing?" Well, that faith still stands, but I'll admit it, my dad's ghost haunted me and I had to change the oil. It has about 3500 miles and 8 months on it, with one filter change at 6 months. I took a drain sample, which I will send off for lab analysis, and if it comes back 'fit for continued service' (which I expect it will) I will let this fresh batch go longer. Anyway, I switched to 10W40 Turbo Formula and the new Amsoil Absolute Efficiency filter.

The whole project took two evenings, about 4 hours total. Last on my repair list this year is the cruise control, which I hope to get to next month.

It's a Dirty Job, But Somebody Had to Do It

2006-05-12T09:58:00.000-04:00

One of the most overlooked portions of detailing a car is cleaning under the hood. Lots of guys will take great pains to keep every grain of sand off the carpet, but don't give a second thought to the grime and good that builds up in the engine compartment. Even many dealers don't bother with detailing the engine compartment, and to me, it really shows.

When the Deville lost her intake manifold gaskets a few years back, my mother in law didn't drive it far, but just far enough to spray coolant all over under the hood. The hole in the wall garage that did the repairs for her did a good job, but they didn't bother to even rinse off the vapor that was everywhere. Three years later, it had baked on and created an adhesive surface that trapped every spec of dirt and oil vapor – needless to say it was a mess, not at all befitting the super clean condition of the rest of the car.

As a former detailer, I'm not shy about turning on a pressure washer under the hood. Back in the 'points and condenser' days of the 1970s, you had to be a little cautious about hitting the distributor cap, and it was usually a good idea to keep the engine running. Modern engines tend to be better sealed against moisture invasion, but the delicate computers and array of sensors create a whole new set of potential problems. I posted the question at Cadillacforums.com, and had an answer within a few hours. NightWolf (a well-read 18 year old from Florida who drives a '92 Coupe Deville) told me he regularly washed the engine of his Cadillac and never had a problem. He recommended that I treat the build up with Simple Green before spraying.

I picked up a gallon of concentrated Simple Green Xtreme Clean at Sam's Club, mixed it 1:1 in a spray bottle, and coated everything under the hood. After soaking overnight, I took the Cadillac to the car wash the next morning, sprayed another coat of S.G. and turned the high pressure water loose. The results were amazing! The baked on crap rinsed away like magic. Some older residue stuck fast, so I re-coated with S.G. and hit it again. It's not show-car clean yet, but the difference is really amazing. I really wish I'd taken a 'before' photo, but here's the 'after' photo anyway.

The Cadillac is still running great, pulling around 15mpg around town, 21-23 on the road. There are three issues that need to be resolved this summer. First and foremost, the coolant transfer tube (which runs from the radiator side of the engine, beneath the harmonic balancer, and back up on the firewall side of the engine) is beginning to rust at the bottom. Here's a bad piece of long-term engineering planning on Cadillac's part, using a ¾ inch steel tube to carry coolant essentially beneath the engine, where it gets lots of road crud and heat, is an invitation to rust. Then they made a junction at the bottom with a 2 inch piece of heater hose – how lame is that? Anyway, I've got to pull that hose apart, sand and paint it, then put in a longer piece of rubber hose to protect it for the ages.

The second issue to be done is a fresh oil change. I've elected on this first run of Amsoil to change it now as opposed to September. I'll still send in a sample for analysis, to determine what state it is in after 8 months and about 35 hundred miles. Last will be the cruise control, which I think is a switch issue. After that, the Cadillac will be back in prime shape.

Spring - I think

2006-04-03T09:31:00.000-04:00

We've had some really nice days so far in late March and early April, so the Cadillac is poking its nose out of the garage quite often. It's so nice to just hop in and go for a cruise, even if it's just the 8 mile commute to work and back home at night.

There has been a change in our garage over the winter. We've returned from the dark side (Chrysler/Jeep ownership) - we're now the typical Michigan household with all Detroit iron in the house. The PT Cruiser just never fit us well, and with one full grown golden retriever at home, and another to be added in the next year or so, it just was not enough car. I bought the car thinking that it would be a gas mileage champion (which it was compared to our Grand Cherokee), only to find out too late that one of the major complaints against the PT is it's crappy mileage. We averaged 17 mpg with it.

My wife took a real shine to the Olds Silhouette mini van after driving her mother's one day last winter, so we went on the hunt for one. It didn't take long. My favorite used car dealer had three in stock, and the one we chose is a 2003, silver with a grey leather interior. With just 43 thousand miles, it's just like new in every way. The one problem these vehicles have, which is a poorly sealing head gaskets, had already been addressed on this van, so we snapped it up. I have to say, despite all the un-manly stigma attached to driving a mini van, this is one finely engineered vehicle. It doesn't have the goodies and gadgets found on some modern vans, but everything is extremely well engineered - and damn is it comfortable! It makes me sad for the demise of Oldsmobile.

Speaking of Oldsmobile, my eyes have recently been drifting toward some of the cars they produced in the 80s and early 90s. In particular, I'm fancying the 90-92 Toronado Trofeo. Built on the same chassis as the Buick Riviera, the Trofeo was a genuine masterpiece of engineering and style. Unfortunately, they didn't sell very well, so there are few of them around, and most of them have a gazillion miles.

Still, if one should happen to turn up with low miles, and the VIC (Visual Information Center) touch screen computer on board, I'd have to give it some serious thought.

The other Olds I've fallen hard for is the 1987-89 Fe/3 Touring Sedan. These are a very sporty edition of the otherwise fairly dull C-Body Olds Ninety-Eight. I never knew these cars existed until I spotted one the other day at the grocery store parking lot. It was in ragged shape, but you could tell that at one time, this was a gorgeous car! The features of the Touring Sedan include a high performance 3800 V-6 with a stiffer Fe/3 touring suspension, full instrumentation package dash, alloy wheels, Trofeo style bucket seats and a console. Sadly, these are even more rare than the Trofeo, but if I ever do spot one of these with less than 100k miles at a decent price, I'd be very tempted to take the plunge and buy it.

Of course, this is all speculative, and has nothing to do with the subject of this blog, which I still love. It would take a unique specimen of one or the other of these cars to get me to give up my 1987 DeVille. It's now at 48k and some change on the odometer.

The Caddy hasn't gone many miles these past few months, but since I repaired the alternator last November, it has been performing flawlessly. The gas mileage is averaging 15 around town, and 21-23 on the road. Say what you will about it's lack of flair or "un-Cadillac-like" performance, this is a finely engineered American car that I am proud to own.

Road Trip!

2006-02-12T08:07:00.000-05:00

Every few months I take a day off from work and make the journey back to my home town, about 90 miles south of where I live now, and take my mom out to lunch. It's typically an enjoyable trip, filled with nostalgia on my old stomping grounds. On February 9th, 2006, it was a blast! This was the first long trip in the Cadillac since last fall when we took it to Clare - that was just days before the A/C compressor seized up to the tune of $900. Obviously, I was hoping for a better experience, and I got one!

Since replacing the alternator, the Cad has been running like a watch. Trouble free, no warning lights or odd behavior - it's driving as one would expect a Cadillac to perform. Since about half this journey home is on divided freeway, I knew it would be a grand opportunity to let the old girl stretch her legs.

I departed in the morning just before 10am. The trip consists of rural two lane roads for the first 20 miles, then a 20 mile stretch of dangerous country highway called M-115, then south on US 131 for 50 miles. That's where the fun began. It hasn't snowed much this winter, so the pavement was dry. I ran the Cad up to 75 and pretty much held there all the way south.

As you can see, traffic was very light. That's a mid-90s N* Sedan DeVille up ahead. He passed me just as I was merging onto the freeway, smiling at my quaint old '87. A few seconds after this picture was shot, I handed him his ass, sweeping by at just over 80 mph. The Cad ran flawlessly all the way, and I arrived a few minutes ahead of schedule.

Our lunch date was fun - mom really got a kick out of riding in the old Sedan DeVille. She especially commented on the supple leather seats, and the near total lack of road noise. We took a short drive north to the next little town of Reed City, where we met my sister at a hole in the wall Chinese restaurant; you know the type: outstanding food - but apparently they don't understand the concept of a vacuum cleaner.

Following lunch, we drove around town and talked for about an hour, then it was time to point the crest north and head home. I hit the freeway running and immediately ran the Cad up to 75, holding that speed for about 10 miles. It occurred to me then that this is where this type of car belongs. Yes, they're fine around town, but Cadillacs are born to be out on the open road, running at cruising speed. Inside the cabin it is so quiet and sturdy, it feels the same going 70 as it does going 35. No shakes, rattles, vibration or wind noise. I cranked up the Bose and decided it was time for a little carbon blowing.

In a matter of seconds, the speedometer was buried at 85, but the pull of the HT 4100 was still increasing. When I felt the speed had reached 95, I held it there for about 4 miles. I could have been going 100 or even 105, and yet it would have been no problem sipping a cup of hot coffee without spilling a drop. Just to prove the point of how sure footed and confidence inspiring this Cadillac is on the road, I took out the digital camera and shot a photo of the speedometer to capture this highlight moment in the trip.

No, I wasn't being stupid. There was hardly any traffic, it was broad daylight, and this was a wide open point in the freeway where I could see for at least a mile in every direction. Had there been a cop around, well, then I might have thought myself stupid indeed.

Coming back to 70 created an illusion...it felt like I was crawling down the road. Exiting the freeway, I returned to a sane speed on M-115, never going over 60. The last stop before home was the BP station in Mesick, where I refueled and checked my gas mileage. It came out to 21.5 mpg! Running that hard over 100 miles and still getting great mileage - not many new cars can equal that kind of performance - let alone most 19-year old Cadillacs. I figure once the cruise is fixed and the engine freshly tuned, I should be able to squeeze 24 or 25 mpg out of the old girl.

Overall, I could not be happier with the result of this road trip. I would have no hesitation to jump in the Cadillac and go to Chicago, or Florida, or anywhere. Sure, it has a few little old car glitches and flaws, but this trip proved to me that for this Sedan DeVille, life is just beginning.

January 1 - A Fresh Start?

2006-01-01T09:10:00.000-05:00

When I bought the Cadillac in late May 2005, it had 45,373 original miles. Today, January 1, 2006, it has 47,801 miles, which means it has aquired 2,428 miles in the past 7 months. At that rate, I'll be driving it for the next 25.5 years to reach my stated goal of 200 thousand miles.

Obviously, we need to step up the pace here. We have one major driving trip planned in the next couple of months, that being a jaunt to Chicago to visit our son in February. Because I have no record of the radiator hoses ever being replaced, and because time with our son is so limited and precious, I probably won't risk taking the Cad on that jaunt, but otherwise, it's going to go everywhere.

So far, considering the original purchase price, insurance, fuel, maintenance, and all repairs, the Cadillac has been an expensive adventure. Total operation expense: roughly $4625 dollars. Divided by miles driven, that comes out to $1.90 a mile. The good news is, the old girl is truly running like a Swiss watch these days, and each mile clicked off reduces that per mile expense.

And when (not if) we reach that 200 thousand mile mark, I have promised my wife that we'll drive the Cad to the junkyard, and she can operate the crusher. Then we'll go to the local dealer, and I will buy her a brand new XLR roadster. She seems pleased with that prospect.

So 2006, here we come. With a shiny silver hood and glittering Cadillac crest proudly pointed into the wind, we're ready for the brand new road ahead.

thumbs up - quietly

2005-12-16T10:36:00.000-05:00

i am writing this in all small letters because that is the printed version of whispering. you see, speaking in a normal voice, or especially in the very pleased tone that would better reflect my optimism, might just jinx things.

here's the update: it's been three weeks and several hundred miles, and the caddy is running like a watch (knock wood, salt over shoulder, prayers of thanksgiving).

we got dressed up last night and went to my wife's office christmas party at the country club. what a kick arriving in a shiny, silent, elegant old cadillac.

shhhh....don't wake the gremlins.

Fully Charged with Success!

2005-11-24T11:11:00.000-05:00

Yesterday, I decided to test my theory that the alternator is slowly dying by driving the Cadillac to work. We made it precisely one mile when the red "No Charge" light came alive, dimly at first, then brighter. So much for a slow death - this alternator was taking a sh** right now. We turned for home and opted for the PT Cruiser to take us to town.

Late in the day, I stopped at my favorite local auto parts place and picked up a remanufactured AC/Delco alternator. The experts at the Cadillac discussion groups say it's not even worth the time to install any of the aftermarket brands - they just don't hold up.

This morning, I went out in the far too cold garage and put it on. Not exactly what I wanted to be doing on Thanksgiving morning, but once I got into it, it was kind of fun. There's something about new electronic stuff; the smell, the feel - it's just cool.

Anyway, the new alternator was installed in about an hour. It's a pretty straightforward job, but man, these sideways V-8s do not leave much room to work on components. After completing the install, I started her up and ran through the diagnostic computer check. The monitored battery voltage, which a few days ago would not go above 11.5 volts, was instantly at 14.2 - exactly where the manual says it should be. I turned on the blinkers, then the lights, and the heater fan; the speed of the blinkers did not change. Success!

So another 150 dollars poorer, I again have a Cadillac that's ready to take me anywhere in style. My wife is wondering now if buying this car was the right move. She hates car problems of any kind. Because of our matching work schedules and the close proximity of our offices, we've enjoyed the luxury of only needing one car for almost all of our 20 years together. We really still don't need a second car, which she believes just invites added expense to our lean budget.

But I was raised in a car family. My dad was a mechanic, and my oldest brother drag raced cars with his best friend in the 60s - he's now a diesel tech instructor at the University of Illinois. Growing up in this environment showed me the fun of owning and maintaining cars. I did a little drag racing myself back in the 70s, plus worked in dealer parts and service departments from AMC, Volkswagen, Chevrolet, and Ford. Cars are in my blood.

So this morning I tried to explain to her the logic behind having patience with the Cadillac, and with me. This car is my hobby, and keeping it on the road is my quest. There are plenty of other hobbies men choose, some less expensive, others considerably more, but nothing that I've found gives me as much satisfaction as this. Like the angel she is, she simply understood. That's why I married her, y'know?

So Many Idiot Lights, So Little Time

2005-11-20T08:43:00.000-05:00

After several hundred miles of pleasureable, trouble free motoring, the Caddy has decided to treat me to another idiot light. This one is called "Service Electrical System." It's amber in color, which in warning light significance means the problem is developing, but not yet serious enough to warrant a "Service Now" amber or the fearful "No Charge" red light. It occurred to me that if Cadillac put honest idiot lights in their cars, they might read something like this...

But again, I've digressed. The factory service manual indicates the "Service Electrical System" light is illuminated if the voltage output at the regulator (built into the GM generator) exceeds 16 volts or falls below 11.6 volts after 5 minutes or more of driving at over 1000 rpms. Apparently in the "C" body era (1984-1992), Cadillac developed a more efficient way to keep the battery charged by monitoring the battery voltage through the ECM computer, then using that data to regulate the amount of charge delivered to the battery.

I have noticed in the past couple of weeks that when the lights were on, the blinkers were a little slower. Last Tuesday on our way home, we had the lights, heater, wipers, and rear defroster all going at the same time - and on pops this "Service Electrical System" light. The battery is not a likely suspect, in that it's a top of the line Interstate only three years old, and that the headlights to not dim and brighten with engine rpms.

A few discussion board posts have confirmed my first guess: the generator or the regulator is slowly failing. For normal daylight driving it's okay for now, but under heavy accessory load, it will eventually die. Yesterday, I ran a voltage output test on the generator and it's putting out 11.8 volts at idle. It should put out between 12 and 15. Under a load it drops down to about 10.

I could fool around and do a bunch of testing to find the problem, and maybe save a couple of bucks in the process, but with the holidays coming, it may be smarter to just replace the alternator and be done with it. AC/Delco remans are 154 dollars. I'll let you know how it works out.

The Great Amsoil Debate

2005-11-08T14:06:00.000-05:00

The last couple of months have taught me something: It's not just religion and politics that can stir up strong opinions. If you really want to see fire-breathing debate, get a bunch of car guys together and bring up the subject of motor oil. It seems every car guy knows which oil is the best, and is convinced it's the only brand any person with an ounce of brain tissue would choose. A female reading this blog will at this point roll her eyes and think, “God, are men really that shallow?” Yes, we are. It gives us something to do while you're in the shoe store.

Of all the things I've written about in this blog so far, the one point that has sparked more impassioned replies is my choice to switch my Cadillac over to Amsoil. For anyone who doesn't know, Amsoil is a synthetic motor oil company with a blending tank and a home office in Wisconsin. Some claim that Amsoil was the first company to market genuine fully synthetic oil for automotive use, predating Mobil 1 by about two years. Until recently, it was only available through a multi-level marketing network of independent dealers, mostly average guys with other jobs, who filled their basements and half their garages with cases of Amsoil stuff and sold it to their friends and families.

It's this MLM network scheme that give most critics a bad impression of Amsoil. Most of us are just more comfortable with products that come from big, traditional retail distribution companies. In addition, Amsoil has never been very restrictive with their dealers, allowing them to make wild and unsubstantiated claims about the miracle qualities of the oil. Google Amsoil and check out a few of these dealer pages. Most of them are honestly enthusiastic, but some go way overboard.

Since I work in the advertising business, that kind of baloney has no influence on me. I'm skeptical of everything except the existence of God. However, if you take an honest look at the science, both Amsoil's and that produced by a number of independent labs, the results show it's a very good product. In most of the critical wear studies, Amsoil beats the products of the major oil companies hands down. On top of my 'beat the odds' genetic-flaw mentality mentioned earlier in this blog, or perhaps as a result of it, I tend to latch on to a subject and study it endlessly. I've read hundreds of pages of data and raw information about how motor oil works, how synthetics are created, motor oil grading and weights, how the molecular structure of synthetics makes them superior to fossil oil, and a score of laboratory studies comparing brands. Only now do I feel I can offer a well informed opinion.

Another factor that troubles so many Amsoil critics is the company's claim of remarkably long extended drain intervals for some of their high-end motor oils. For the type I use in the Cadillac, they recommend up to 25 thousand miles or 1 year, with only a filter change at the six-month mark. Frankly, that troubles me, too – even though I've read oil analysis studies of vehicles using Amsoil (some that have gone mind-boggling distances between changes) that indicate the oil is fully capable of remaining in service well beyond that limit. Yet my dad was an auto mechanic most of his life, and he taught the 3k rule like it was the 11th commandment. That kind of conditioning is hard to overcome.

The truth is, the 3 thousand mile oil change interval is a fairy tale, and always has been, even for fossil oil. Read this quote from Dave Mann, a 19-year veteran lubrication specialist with Ford Motor Company:

“When looked at from an engineering and chemistry standpoint there is absolutely no way an arbitrary number such as 3000 miles can be recommended and specified for all cars and light trucks. The 3000-mile oil change is more of a marketing program headed up by the major oil and quick lube companies fighting to retain the 3000-mile oil change.”

To my knowledge, there has never been a study done that conclusively proves a short duration oil change interval extends the life of an engine, but there is plenty of science out there demonstrating that longer intervals do nothing to reduce engine life. For my circumstance, I will run the Amsoil for one full year, but since my Caddy is an occasional driver, it will only get about 6 or 7 thousand miles of use in that time. I plan to do regular sampling of the oil – every thousand miles from the 3 thousand mile mark, and have it analyzed at a lab. The results will be posted here for anyone who' s interested. If this test demonstrates that Amsoil doesn't measure up, I'll admit defeat then go back to the car guys and ask for a recommendation.

Then I'll stand back and let them fight it out.

An Autumn Cruise

2005-11-02T20:51:00.000-05:00

My wife has lately gone crazy over this little shop in Suttons Bay, about 15 miles from my office. She's especially enamored with a brand of rustic wood bowls they sell. She's bought just about every style they make, except one. She mentioned last weekend if I had any spare time this week, I could run up there and get that last bowl for her collection.

Today was the day. Work was driving me crazy, and the weather was absolutely stunning. In our corner of Michigan, a day like this in early November is some kind of gift. All the signs were pointing for me to just jump in the Caddy and go.

To confess, I actually had it planned to go since yesterday. With all the money and time I've spent getting this DeVille back in shape these past few weeks, I really wanted to get it out on the road and enjoy the fruits of that labor. I also grabbed the digital camera on the way out of the house this morning to capture a few images along the way.

Leaving town, I flipped on the radio and let myself be wrapped in that sweet Bose Symphony Sound. Okay, so I was listening to Shawn Hannity on AM; but damn - even that sounds grand on this system. Traffic was light and the 4100 was feeling fairly frisky, so once I hit the open road, 60 was an effortless exercise. The road I took winds along a beautiful blue-green bay, offering almost constant scenic vistas. The almost new General tires contributed to a silent, silky ride. It was like being in a Cadillac TV commercial from 1987.

First stop was a boat launch about halfway through the trip. Since most boats are tucked away by this time of year, it was a fair guess the place would be deserted, and I could shoot some decent quality pictures without a lot of background clutter. Here's the the best of those...

Suttons Bay and the little shop arrived all too soon, even though the first half of the trip took me over 40 minutes. I went in and bought the bowl she wanted, stuck it in the trunk to surprise her later, and wheeled back out of town.

Heading south, I thought about stopping at one of the small wineries that dot this area to shoot a few more pictures. Most of them make great backdrops, but unfortunately most of them are also closed during the week in the late fall. So I just stopped once more at the boat launch, and using the camera's self timer, shot this self portrait...

Even if nobody ever reads this blog but me, this picture will remind me of a nice fall day, a sweet 1987 DeVille running at it's best, and a 1 hour cruise that left me feeling better than I did before it started.

Everything's Cool

2005-10-29T21:10:00.000-04:00

Forgive my momentary slip of melancholy in the last post - I love this Caddie!

The coolant fan problem is no more. It was a pretty easy fix. I elected to give the junkyard modules a chance, so this morning it was off to the big boneyard here in town to retrieve one. This place is a curious mix of the ultra-modern yard, where parts are pulled, inventoried, and stored in a warehouse; and the old fashioned junk dealer, where they still let customers wander about the yard and pull whatever oddball stuff they might need. Gratefully, the fan control module on an '87 DeVille fits in that oddball category.

It was cool and foggy at 9 this morning when I arrived at the yard, the back seat of my PT Cruiser loaded with tools and my Cadillac service manual. The guy at the desk gave me a printout on how to locate the two '86 DeVilles they had in inventory, and off I went into the bowels of the graveyard. It's pretty slick at this place - all the cars are set on stands made of steel pipe, resting about two feet off the ground. I found the two DeVilles right where the paper said they would be.

Removing the module from the first car was pretty easy; I had it out in about 10 minutes. It's located right behind the headlight assembly on the left front of the car; about the size of a deck of cards, with a big finned heat sink on top. It's held to the sub-body by two small 7mm bolts, and all the wiring is attached with removable connectors. All I needed to remove is the left directional assembly, and the windshield washer fluid jug. Giving it a bit of thought, I decided it might be a good idea to pull the one from the other car as well; for 10 bucks a piece, it might save me another trip out here if the first one didn't work.

When I got home, I really had no intention of changing out the new module in my Cadillac today, but my blessed wife said, "might as well finish the job, honey!" You gotta love a woman who understands these crazy male obessessions. Of course, she loves driving the car, too...

Swapping the new module in went even quicker, as in '87 Cadillac moved the washer fluid jug to the other side of the engine compartment, and cut bigger access holes in the radiator frame to get to the wiring. After putting in the first module, I got into the diagnostic mode on the onboard computer, switched to the manual fan control override, and hit the "High" button to run up the speed of the fans. It took several seconds for them to start, then I heard that magical sound of BOTH fans revving up to full speed!

Second test was to turn on the A/C full blast, when the fan module is supposed to default to running both fans at full speed. That worked perfectly too. The third test was to let the car warm up to operating temp while sitting still, to see if the fans started when heated engine coolant started flowing into the radiator. Passed again. The first module was working exactly as it was supposed to.

I was elated! There's nothing quite like the feeling of success when you're able to track down, diagnose, and repair a problem yourself. It's one of the reasons I bought this car to begin with. Some people just don't get that. They'd rather have new cars so they can just turn the key and go, and when problems arise, they give it to the dealer and let them fix it. Don't get me wrong, that's great if you don't mind a big car payment every month; not to mention driving something that looks just like what everybody else is driving.

Now I'm down to just one existing problem - the cruise control. I think I'll take the winter off, and tackle that one in the spring.

And the Hits Just Keep on Comin'

2005-10-28T21:08:00.000-04:00

Sometimes, I really have to wonder whatever possesed me to buy a 19 year old Cadillac. So far I've owned it about four months, and all I've done is spend money and time on it.

Then I take it for a drive.

Remember those old TV commercials that described "Cadillac Style"? Whoever wrote that campaign is a genius who deserves a condo in the Caribbean and all the Rum punch he or she can drink. This car drives so nice it's almost sinful. Like a guy told me once. "There are very few cars you can get in and drive 100 miles, and feel better when you get there than when you left." He was talking about a Lincoln Mark 5, but my '87 DeVille fits that category very well. Now if I could just get it to go 100 miles without breaking something!

Latest on the hit parade is something called the Coolant Fan Control Module. It's basically a little variable voltage computer that resides behind the left side marker light. It receives signals from the engine computer, which monitors the coolant temperature constantly. When the coolant reaches a certain temp, the Coolant Fan Module is instructed to run one or both of the electric fans located behind the radiator. This cools the fluid in the radiator, which then flows back into the engine. In the old days, the fan was hooked to the front of the engine and ran constantly. But since this 4100 V-8 is mounted sideways, it requires this rather elaborate setup.

I'd noticed before that the smaller of the two fans on my Cad ran constantly, but the larger fan never ran. I also noted that from time to time, the "Coolant/Temp/Fan" light would come on on my dash, mostly on hot days while idling at a light. From these two conditions, I deduced that either the fan was shorted, the Coolant Fan Module was not working, or the temperature sensing unit may be faulty.

As I may have said in previous posts, I was smart enough to purchase a GM factory service manual for my Cadillac from e-Bay, and it's been a gift from heaven. You see, for all the wrong things Cadillac did when designing this car, one of the most brilliant strokes they included is an on-board diagnostic computer, built right into the climate control panel on the dash. All I need to do is hit the "Auto" and "Warmer" buttons simultaneously, and the panel switches over to the diagnostic mode. It lists trouble codes, returning both intermittent and hard (constant) problem codes for almost every system on the car. With my service manual, it's simple to translate those codes into a real actionable diagnosis.

The computer on my car gave me three codes, E47, F41, and F48. The E47 code showed an interruption in the computer's data transfer (this a result of the computer shutting itself down when the A/C compressor died). F48 was also related to the A/C problem, but the F41 code caught my attention. That meant a 'cooling system fan' problem. The manual stated that this code would activate the "Coolant/Temp/Fan" light. Ah hah!

The manual then directed me to a seperate diagnosis page for my code. It's a great little Q & A chart that you follow until you trace the source of the problem. I was instructed to disconnect both fans, and take the connector from the inoperable fan and jumper it with wire to the known good fan. If the good fan ran, I needed to replace the inop fan. It didn't run, which indicates that my Coolant Fan Module is bad. Just to be doubly sure, I plugged the good connector to the bad fan, and it started right up and ran perfectly. I also measured the output of both connectors with a voltmeter. The good connector showed 13 volts, the bad connector less than 6. From the on-board computer I can also manually control the the fans from off to full speed, but doing this neither changed the voltage or the fan speed at either connector.

Now the key is finding another module. It's still available from Cadillac - for 310 bucks! Or I can get one from a discount GM parts outfit online for $145. My local boneyard has two '86 DeVilles, and he'll sell me the module for 10 bucks if I pull it.

I'll let you know which direction I go in the next post.

A/C Crash

2005-10-22T12:57:00.000-04:00

When I purchased the Cad, I knew the air conditioning didn't work. It had been diagnosed with a bad compressor two years ago, and this week, I found out just how bad it was.

Actually the problem started after the last time my wife drove the car. Hmm...
But I digress. She told me that when she got home the car smelled hot, but not like antifreeze. I checked it out and found significant noise coming from the serpentine belt area. A bit of investigative work narrowed it down to the air pump, water pump, or compressor. During the diagnosis time, the noise got so loud it became impossible to determine which component was acting up. I pulled the belt and turned all the pulleys, and everything seemed free. The way Cadillac (it's the same with most serpentine belt equipped cars) has engineered the system, there's no way to isolate individual components. Then I noticed - of all things - SPARKS coming from the A/C compressor housing! I had my answer.

The other problem with the serpentine system is that if any of the components fail, the car becomes undriveable. Don't get me wrong - the serpentine design is an excellent innovation in terms of maintenance. The belts last much longer, and the components run more efficiently; but in terms of emergency cobbling - there's not much you can do.

With no experience on A/C systems, and no tools to work on them, I knew this was outside my ability. I took a gamble and decided to attempt driving the car to the local A/C shop, about 6 miles from my house. I made it three miles before the compressor siezed completely. The "Service Soon" light came on, followed a few seconds later by a total shutdown of the Climate Control panel, the Fuel Data Center, and the speedometer stuck at 50 mph! That made me nervous.

The tow truck driver was a really nice old guy, but he still stuck me for 45 bucks to haul the car three miles to the shop. Oh well, he's gotta make a living too.

The shop is actually an old family owned tire store, but they hired a freelance A/C tech named John a few months ago, and he's got a great reputation. He's earned it. This guy is awesome. John looks like Grizzly Adams, but he knows his stuff. He ordered a new compressor from the local Cadillac dealer, who had to import one from another dealer in Texas. It took a couple of days to get here, but once he had it, he worked non-stop to finish the job.

We picked up the Caddy this morning, and everything is working just as designed. It even blows cold air. Of course, here in the hinterlands of Michigan we won't need air for another 8 months, but Cadillac's climate control system depends on everything working properly for anything to work properly. I set the thermostat to 70, and obediently the heat kept me cozy all the way home.

The total bill - $972.35. Yeah, it hurts - but I planned on getting the air fixed next spring anyway. It's nice to have the old girl back in proper trim again.

On "Drivers" vs "Collector Cars"

2005-10-08T09:34:00.000-04:00

I recently invited a retired Cadillac technician to read this blog and offer his comments. His reply was polite but somewhat condescending; and it got me thinking.

He said that my technical descriptions were accurate and well presented, but that I might be wasting my time with this car because it's not an 'object d'art.' In terms of 'design and distinctiveness,' according to him, the mid 80's was one of the darkest eras in Cadillac history, and that these cars should be thought of as mere 'drivers' (that is, a car to be driven until it is used up) as opposed to 'collector cars.' His car by the way is a gorgeous '83 Eldorado Biarritz with even lower miles than my '87 DeVille. Very much in the collector car category.

In one way he's right. My DeVille is not going to wow anybody at the local show and shine. Compared to other years of Cadillacs, especially the new breed of superb sports sedans they are producing, it is an ugly duckling. Yet I've owned my share of so called 'collector cars,' and while that is very nice, it tends to be a purely extrovert experience - i.e. no one drives (or trailers to shows) a mint condition '67 Chevelle SS 396 or '63 split-window Corvette because it's a marvel of engineering, or even supremely comfortable for that matter. These cars are objects of desire, and people want to own them to impress others. Simply put - "See my car? It is cool, therefore I am cool."

The downside to owning a collector car is that you are constantly fretting over every rut in the road, every bird that craps on it, every stone that goes 'tink' off the undercarriage. Dust is your worst enemy, rain your worst nightmare. You park in the most remote corners of every parking lot to avoid door dings, and you spend enough on waxes and cleaners and chamois cloth to bail out a third world country.

So given the choice, I'll take my 'driver' any day. As you can see from the pictures, it's in great shape, it's amazingly comfortable, and it rides every bit as good as any other Cadillac I've ever been in, despite it's diminuitive size. That Bose "Symphony Sound" stereo is absolutely sublime, too. Let me tell you, if I combined the driving experience of the half dozen collector cars I've owned, it wouldn't begin to measure up to the cradling pleasure of wheeling this butt-ugly Caddy down the road.

And this Sunday, when my wife and I make our semi-annual pilgrammage to the little town of Clare, Michigan, we'll happily glide along down the highway earning 22+ mpg, park wherever we please, and if birds crap all over it, or it rains or heaven forbid snows, we'll pop into the 5 dollar car wash and let 'er rip.

In short, we'll be simply enjoying our old "driver," while all those collector cars (at least here in the great frozen north) are tucked away in climate controlled garages under padded custom covers, doing nothing but taking up space while they wait for the next car show season.

2005-09-19T12:11:00.000-04:00

Antifreeze, Horse Pills, and Amsoil

Another step taken toward preserving this Cadillac for the ages. Because the previous owner (my mother in law) couldn't remember the last time the antifreeze had been changed, I decided to get it done now. Both of the 4100 posting boards I visit recommend changing the coolant and adding the sealer once a year, or every two years minimum.

The service manual mentioned that the coolant must meet the GM-1825M standard, which I later found out most major brands do. Next purchase was the coolant supplement (sealer). I chose to buy the GM branded stuff (I'm told Bars Leak makes the identical product, but since GM's is only $4.50, why switch?). It comes in a blister pack of six "pills" about the size of a 3/4 inch socket.

The manual also said to drain the old coolant away by opening the radiator drain (it's on the driver's side, lower corner of the radiator, a small plastic plug that screws in), and two cylinder block drains. I never could find those - and the manual had no illustration as to where they might be. After reading several posts on the topic, I felt comfortable that draining the radiator and fresh water flushing the system was adequate. I got about two gallons of coolant just from the rad, and the system is just over 3 gallons capacity. Then refilled the system with distilled water, ran the engine for 10 minutes at about 2000 rpm, drained off the flush water, crushed and added the sealant pills directly to the radiatior, and refilled with undiluted antifreeze. Another run of 10 minutes or so mixed what was left in the block with my fresh antifreeze, and I'm good to go.

The only matter of concern was that during the flushing cycle, the idiot light (What the heck does Coolant-Temp-Fan mean anyway??) came on after a few minutes. I kept adding more water to the coolant tank next to the radiator, and eventually the light stayed off.

The other trick was getting the radiator full with the fresh antifreeze. It's almost a two-person job. One to keep the engine running at high idle while the other tops off the radiator. I tried doing it by operating the throttle by hand while pouring - not recommended!

Finally, I also changed oil this weekend. I'm switching all my vehicles over to Amsoil. Some people don't like it, but they can't really give me a reason other than it's expensive. It's actually not much more than any other synthetic when you get the preferred customer discount (which is available to anybody at their website). Plus, I like the fact that it's completely synthetic and made in Wisconsin - not much left these days that's still manufactured in the USA. The final selling point for me was Amsoil's claim that you no longer need to change oil every 3 thousand miles. They say that benchmark was established by the oil companies and the auto manufacturers to create more business for dealer service departments and sell more oil. As a former employee of various parts and service departments, that doesn't sound like a conspiracy theory to me.

Amsoil says you can run their oil for 25 thousand miles or 1 year, changing only the filter at 6 months. Some may say that's foolhardy and risking my engine - but if Amsoil is making that claim publicly - I have to believe they have sound data to back it up. I would never sue them should my engine blow, but surely some people would! Besides, when is the last time you heard a manufacturer make a recommendation to buy LESS of their product? To me, that means something.

2005-09-11T08:46:00.000-04:00

Replacing the blower motor control module was a breeze. The local boneyard took one off a '90 DeVille and charged me $20.00 for it. Three bolts, two electrical connectors, and about 15 minutes later - the fan works just as Cadillac intended.

A word to owners of Cadillacs which use this generation of Climate Control System (about 1982 through 1992): If the fan starts running and will not stop - this is a simple repair you don't need a shop to diagnose and charge you a small fortune to fix. The control module on most models is located on the firewall, atop the blower motor housing, almost in the center of the car. There are two connectors running to it, one with four wires and the other with two wires.

This device is the electronic speed controller for the blower (Cadillac calls it the Blower Motor Driver Circuit). When it fails, either the fan doesn't work at all or it runs all the time. In the latter case you actually have to unplug the fan to get it to stop. You can't repair the control unit, only replace it.

2005-09-09T08:52:00.000-04:00

If you're new to blogging, it's important to know that to read a chronological blog like this one, you must start at the bottom. In other words, you must scan down the page (or select the link to the left) to read the introduction, then work your way up. The newest post appears at the top of the page.
Enjoy!

2005-09-08T16:21:00.000-04:00

The Beginning - September 2005

If a picture is worth a thousand words, this one is worth 45 thousand miles. 45,373 to be exact. That's the starting point on my quest to get 200 thousand miles from an HT-4100 equipped 1987 Cadillac DeVille.

Truth be told, I enjoy several advantages over the average nervous 4100 owner, many of whom gnaw their fingernails into bloody pulp everytime they get more than a few miles from home, expecting the engine to explode at any moment. My lucky stars are these:

1) I know all the previous owners of the car, have a good relationship with the dealer, and have nearly every service record from the day it was delivered.

2) As a former drag racer, I have just enough shade tree mechanical ability to tackle most of the problems that might crop up.

3) Most experts (or at least the guys I hang out with at a Yahoo Group called "HT4100 Exchange") agree that by 1987, most of the severe problems with the 4100 had been resolved. Therefore, this blog may be of little comfort to owners of 82-86 Cadillacs. However, I'm not free of worry. This engine needed the intake gaskets replaced about a year ago after coolant began running out of it like a monsoon rain, and for the last few years, it's been serviced by a little hole in the wall place similar to the above described "Joe's Garage."

Now, let's begin the journey with a very brief history of how I ended up with this car. It was sold new by a local dealer to an elderly couple who drove it very little. They both ended up with Alzheimer's Disease in the late 90's, and my mother in law (who is a professional home caregiver) was hired to care for them. After they died, she was offered the car by the couple's daughter. At that time it had just 14 thousand miles. She jumped at the chance. On the wages of a school cook and caregiver, she never dreamed she'd own a Cadillac.

She drove and maintained the car like it was made of glass. In winter, she stored it indoors under a custom cover. Every few weeks while she was driving it, she would take it in for some new belt or hose, a tune up, tires, or 'just to be looked at" by the wrench benders at her favorite garage. The worst problem occurred two summers ago, when the intake gaskets failed and she nearly overheated the engine. This can be devastating to the aluminum block, but there appeared to be no long term damage here. Luckily, the gasket replacement did the trick, and she had no more serious troubles.

During the five years she owned the Caddy, I had the opportunity on several occasions to drive it on relatively long trips...pure motoring joy. Those readers who own similar models will nod in agreement when I say there's nothing like that Cadillac glide. They simply float down the road as if on a cloud - yet these smaller front-drive models also stick to the road and handle like a sports car. I've only owned one other Cadillac in my life, a 1966 Coupe DeVille with the silky smooth 429 V-8. While that was a nice ride, it literally swayed like a Chris Craft during lane changes and practically stood on the door handles on sharp curves. Not to mention it drank gas like a sailor on three day leave in Shanghai. This '87 DeVille had road manners I'd never experienced before, was every bit as smooth and silent as my old two ton '66, and sipped fuel at a stingy 24-25 mpg. I was hooked.

By summer of 2005, my mother in law was ready to sell the Cad and I was ready to buy. My wife had other ideas. Her tastes run more toward the BMW Z-4, or the new Pontiac Solstice, and she adamantly opposed our buying that "stodgy old lady car." A little gentle persuasion on my part, and a jaw-dropping price ($2800) for such a low mileage car changed her mind.

So that's how it got in my garage. Now what?

I should mention at this point that the Cadillac is our second car, and gets little actual daily driver use. First choice is a 2001 PT Cruiser, which we picked up after dumping our V-8 powered Jeep Grand Cherokee just as gas was crossing the $2.25 a gallon threshold. We mostly drive the Caddy on weekends and pleasure drives, and occasionally as a commuter.
It's nice to not have to rely upon it, and that gives me the luxury of working slowly on repairs.

Even though it's a low mileage survivor, the Caddy has some issues. Because my mother in law has no garage of her own, the car sat out in the sun for five summers. The result was that the color coordinated paint on the rubber trim around the rear bumper and the body side molding has faded completely away. Also, the molded rubber trim around the body-colored rear window bezel disintigrated into a bunch of 3-inch pieces. There are numerous parking lot nicks and scratches. the air doesn't work, and the cruise has gone absolutely looney.

Just last weekend, the blower on the climate control system started running and would not stop. Even with the key off and removed from the switch, the fan kept running. Luckily, shortly after buying the Caddy I picked up from e-Bay a factory service manual for the '87 DeVille, and after scanning the outstanding diagrams inside, I was able to trace the source of the trouble: a faulty blower motor control module. A bit of internet research showed this is a common failure item in all years of Cadillacs that used this CC system, from about 1982 through 1992. I'll pick up a new module this weekend at the boneyard and replace it.

More later...

Introduction - Attempting the Impossible

2005-09-08T07:56:00.000-04:00

In the early through mid - 1980s, the Cadillac division of General Motors created a superb series of automobiles that unfortunately were powered by one of the worst engines ever built. The HT-4100 (HT stands for High-Tech) was supposed to be an engineering marvel, created to conform to government fuel economy standards, mounted transversely in smaller, leaner luxury sedans and sports coupes that would define a new era for Cadillac. It would end up being such a debacle that it nearly brought this storied automaker to the brink of extinction.

The primary problem with this engine is in its metallurgy. For some reason only the Cadillac engineers can discern, they chose to mate a state of the art aluminum engine block to old-fashioned cast iron cylinder heads. This blending of dissimilar metals created a series of issues that would ultimately put the 4100 on the Popular Hot Rodding list of the The Worst Automobile Engines Ever Created. The 4100 is also one of the few engines in history that is specifically excluded from coverage on almost every major extended warranty plan offered. Many shops simply refuse to work on them, because the incidence of repeating problems is so common.

In brief, here is the chain of events that makes this engine so prone to self-destruct: The aluminum used in the block is not stable enough to meet the extremely close tolerances required to prevent leakage of water (antifreeze) into the oil. As the engine goes through cycles of heating and cooling under normal operation, the surfaces where the aluminum and cast iron parts meet begin to lose contact. Eventually the fiber gaskets between these surfaces are unable to hold back the coolant, and it spills into the crankcase oil. The oil turns into an acidic brew that no longer lubricates; instead, it destroys the crankshaft bearings and camshaft lobes. Making matters worse, Cadillac owners tend not to be the type who regularly open the hood to check oil and antifreeze levels. Even if they did, it's unlikely they would understand the relationship as the coolant level dropped while the dipstick level increased, or recognize the danger when normally honey-gold colored oil changes into something resembling Cream of Mushroom soup. As the coolant level dropped the engines ran hotter, until they eventually overheated, which caused catastrophic warping of the block and accelerated the leakage problem.

Cadillac knew these issues existed well before the first HT-4100 was installed. Their response was a lame form of reverse engineering: a single paragraph in the owners manual stressing to owners the importance of changing and flushing the cooling system at least every two years, and most critically, to add a blister-pack of "coolant supplement" pills with every change. This "supplement" was actually a re-packaged form of good old Bars Leak, made from ground ginger root (isn't that a spice?), which sought out and plugged gaps in the cooling system. Of course, if the owner didn't read the owners manual, or had the car serviced at Joe's Garage - where Joe perhaps didn't know about this fatal flaw - they were headed for major trouble, and soon.

As you might expect, this chain of events destroyed more than engines. It caused an enormous meltdown at Cadillac dealer service departments. It got so bad that by 1985 GM was sending out replacement engines by the truckload on a weekly basis to many dealers, and picking up stacks of blown engines in return. Warranty costs soared, and Cadillac customer satisfaction dropped to an all-time low. The 4100 engine disaster came close on the heels of the V8-6-4 Displacement on Demand engine of 1981 (read more about that at the Worst Automobile Engines page). The public and the automotive press began to wonder if Cadillac's stature as a marque of engineering excellence had passed.

At the very same time Cadillac customers were watching their expensive machines self-destruct, Toyota was launching the superb Lexus luxury cars, Nissan was developing the Infinity lineup, and Mercedes and BMW were introducing models in the same price range as the Cadillac DeVilles. Lincoln was still building their luxury-liner Town Cars on the aging but reliable rear wheel drive chassis. The result was predictable: Cadillac owners lost faith, and switched brands by the thousands.

In the end however, the 4100 was not the demise of Cadillac. With the 1988 model year, Cadillac revamped the 4100 into the 4.5 liter, then later the 4.9 liter, both of which were far more reliable engines. These were followed by the awesome Northstar powerplants, which many experts believe to be one of the best mass produced engines ever devised. Combining these engineering successes with a brash young styling department, Cadillac has not only survived into the 21st century, it has been reborn.

Okay, enough with the history - what the devil is this blog all about?

If you haven't guessed by now, I happen to own one of these mechanical bastards. It takes the form of a 1987 Sedan DeVille, silver in color with matching grey leather interior. When I bought it three months ago, I knew nothing about any of the preceding information. A casual comment by a mechanic and research on the internet has educated me: I now know the potential swamp I have waded into.

Yet I remain undaunted. Through some genetic flaw, mental instability, or unresolved childhood trauma, I am the type of person who believes that I can beat the odds. If I had been on the Titanic, I would have drowned believing the old girl truly was unsinkable.

So this car has become my quest. I want to prove that somehow, this Cadillac is the one they built right. Good Lord, it's almost 20 years old and still running, alibet with only 45 thousand original miles. Still, some twist of fate put this automobile into my hands. My goal is 200 thousand miles.

Impossible you say? Maybe, but I'm going to try. Perhaps along the way I can help a few other mid-80s Cadillac owners who find themselves in the same boat (pun intended) to learn by my example. Stay tuned for the updates.