I put a new alternator in shortly after purchasing the car.
I put a new windshield in because the old one was chipped from age.
Was about to replace the exhaust system, which had rusted through, right before I got rid of the car.
It was the most reliable car I've ever owned right up until the day the HT4100 engine blew up at 86,000 miles and I had to scrap the car.
Other maintenance items it didn't NEED, but I had done because I loved the car:
- New thermostat
- Radiator drain and flush
- New spark plugs, wires, distributor cap and rotor
- Regular (2500 mile) oil changes
- New PCV and air filter and breather
- New brakes
- New tires.
Cosmetic repairs I made:
- Rolls-Royce grille
- Limo-tinted windows
- New dashboard
- New hood ornament.
I know people say that with proper maintenance and care, these HT4100-equipped Cadillacs will last forever, but I don't think that is the truth. I knew about the problems with the 4100 and I took the appropriate steps: Radiator drain and flush, clockwork oil changes, etc., and my car still died on me. It never even showed signs of stopping or of future problems until the day it conked out.
I was driving to work and I heard a crunching, rough sound under the hood. In the split second it took for me to think "Hmm, that sounds bad, I should pull over and have a look," the car had died and I was drifting to the side of the road.
Other than that it was probably the nicest car I've owned yet. It gave decent fuel economy (15-22 mpg), it was extremely quiet, handled nicely, and got nice comments from everyone who saw it. The 252-cid V-8 was extremely underpowered for the size of car it was pulling, and it took awhile for the car to accelerate in situations like getting onto the Interstate. Once the car got up to speed, however, it rolled from 45 MPH and up without a hitch.
It was painted in a very attractive dark blue/black metallic color called "Twilight Blue Metallic." The interior was blue leather. It had excellent legroom and an attractive dashboard which made navigation easy. It even had a factory cassette tape deck!
This car really broke my heart. I used to spend hours cleaning and detailing the car and keeping it in tip-top shape. It died anyway. I tried selling it to someone who could afford to put a new engine in, but to no avail. I didn't have the $2000 it would have cost, so I had it towed to the scrap yard. I watched them crush it.
If I could tell a prospective HT4100 owner one thing, it would be this: Buy the car if you want it, enjoy it while you can, but don't get too attached, because you never know when the end is going to come.
Why did you not just put a chevy engine in. They're all the same and 200 bucks gets you a 350ci. At least here it does.
A chevy 350 would not work in the Deville.
A. You get no warranty if you change the motor that was originally in there.
B. You need to change EVERYTHING else. Deville's were not made to handle the thrust of a 350 and the tranny's weren't compatible. The 4100 is a garbage motor.. I replaced mine when it blew and it blew again so I sold the car for 600 bucks. E-mail me @ jeeptj72@aol.com if you have any questions.
First, I think you severely underestimate the ht4100 they had their problems, but I have heard quite a few good comments about them.
Second, You should have kept the car until you could have bought either a new ht4100 or other compatible engine I have heard that the caddie 4.5 and 4.9 are compatible and are more reliable the 4100. It breaks my heart that you had such a nice car crushed.
Jeff.
It breaks my heart too, that you had such a nice car crushed.
My car is an '84 DeVille. It's been a "One Family" car since it was a new car. I bought it from my uncle about 5 years ago when it only had 28,000 original miles on it. I've put about 80,000 miles on it since then (it now has 108,000 miles).
I've been scrupulous about getting oil changes every 3,000 miles and flushing the radiator out once a year. I've also replaced numerous parts simply because I thought it was a good idea. Rubber dries out after a while and I've replaced most of the rubber parts under the hood. My last major undertaking was asking my mechanic to fix all the things that were leaking under the car. (Same mechanic since the car was new, I might add.) I've also replaced the rear air shocks, etc.
My car died out this week and coasted to a stop. None of the lights inside ever came on and the car didn't smoke. I thought it might have been the alternator or a fuel filter. I had the car towed to my mechanic.
One fuel filter was totally clogged, but he also noticed that the car had very little fluid in the radiator. He has tried to reseal the head gasket with something that has come out in the last couple of years -- but we don't know if it will take or not. Right now he says the engine seems "kind of flat" but he's not saying I should replace it yet.
Worst come to worst, I will replace the engine. According to my mechanic, they have new rebuilt engines that have steel shields on them (supposedly better than the original engine). He does not recommend a reconditioned engine. He says the rebuilt ones come with warranties, etc.
I too, baby my car. I am hoping to get about 300,000 miles out of this car. I love the fact I have no car payment. I love the "land yacht" aspect. The car runs great, gets very good gas mileage (24 mpg highway), and has loads of room. It's just an exceptionally good car. With no car payment, I can afford to put money into fixing it.
I'm terribly sad that you had a perfectly good car taken to the junk yard. Yes, engines cost money, but so does buying another car. I'm putting my money into fixing the one I have versus looking for something else to buy.
The 4.5 and 4.9L engines would not have worked in an '82 Cadillac because they are transverse-mounted engines and the '82 was a standard engine. Perhaps a 425/472/500 Cadillac engine would have worked, but at the time I needed a daily driver and didn't have the time or money to be searching around for an old engine to put in the car.
It seemed silly to me at the time to take out a loan to put a $2000 new engine in a car, when I could get a whole other car for $2000 or so. Considering that the '82 deVille needed a whole new exhaust system, new rear wheel cylinders, a new vinyl top, and other small repairs, it seemed better to just scrap it. I was able to part out a lot of the good things about it and sell them to get some money. I ended up getting a '77 Sedan deVille for just over $3000, with only 46k miles on it. So I did. I later sold that and bought an '84 Lincoln Town Car for $2200, which has served me much better than any of the five Cadillacs I have owned. I sometimes wish I could have kept the '82, but hey, hindsight is 20/20. At the time, I did what I had to do.
I don't believe Cadillac should ever have produced this motor. I could not have taken care of it better and it blew twice. I had this car looking like it came out of the showroom and anyone I encountered gave me the famous HT4100 lecture and they all told me to get rid of it. I did not listen. I did however score a brand new jeep wrangler, but I totalled that out anyway within one year.
I have a 1983 Fleetwood with the 4100, and THAT is an underpowered car. I figure that, with some modifications, I could get a 368 to go in (they put them in the Limo version). That is, of course, if it's not one the 8-6-4 deals.
Was there a power-train mistake that Cadillac did not make in the 80's? I just replaced my 4100, and I want to make it at least 10,000 miles before the next problem.
The 368 cid engines with the 8-6-4 feature are the same engines as the other 368 Cadillac engines and the 8-6-4 feature can be easily disabled while installing the motor in the car.
I currently own a 1985 Cadillac Seville with the HT4100 engine also and I've read the previous comments about that engine. I'm wondering if a 4.3 liter v6 engine from a Chevy s10. I haven't actually taken a closer look at how the trans./engine connection bolt together to see if it could bolt right into that transmission. This is just a thought I had from hearing about those engine conversions.
I have a 83 sedan with the 4100 engine, I like my car too,
but my engine is weak runs, but weak and now my tranny will not pull because of that, I'm thinking of replacing my 4100 with the 368 cid, if I can make the switch with little or no problem.
I own a 1982 Cadillac Coupe Deville with a V-6 engine, 92,000 miles, Original 8-track, Floor Mats, and Hub Caps. I paid $1500 for it and I believe it was money well spent. I am the second owner, the previous was an older man who used the car for running to the store and church. The only concern I had with buying this car was the fact that it wasn't a V-8, But after reading what you guys have written I feel better. I previously owned a 1979 Coupe and I really haven't been able to tell the difference in power or gas mileage, they both take off slow, but get up to speed quick and maintain good. I'll be putting it on the road for the first time to attend the Tennessee Vols and Kentucky game. I guess I'll get back with you then and let you know how she does...
I have an 83 Eldorado with the HT4100,& so far I have been very pleased with its performance. This engine has the potential to be very reliable with a few modifications. I purchased this car at 94,000 miles with a blown head gasket. Before I began to fix it, I did my homework on the 4100. I found mass amounts of information about it. This engine is very complicated & bolt torques must be EXACT. This engine uses cylinder inserts completely surrounded by antifreeze. The Block is made from an aluminum-alloy, & the heads are cast iron.
First of all, in 1983 gasket & casting technology were not as good as todays. As a result many 4100's have a nasty reputation for blown head gaskets & engines failing due to coolant contamination of the engine oil.
Second, there were several inferior parts used in the original 4100's which general motors has issued Technical Service Bulletins for. The worst being the camshaft. The GM supplier of camshafts for the 4100 was caught using inferior quality metals for camshafts. As a result the camlobes would round-over very quickly. Replace the Camshaft with a "NEW", not reground, camshaft & that problem is solved. There is also a service bulletin for the 4100 that states that the original intake manifold gaskets may seep anti- freeze into the engine oil. Replace the intake manifold gaskets & that problem is solved. The service manual procedure MUST BE FOLLOWED EXACTLY when toquing the intake manifold bolts. The Engine oil pump was a very poor design & does not provide sufficient oil pressure & that by itself will slowly destroy the engine. Replace the Factory Pump with a new aftermarket model. The head-bolt torque has been revised. The new bolt torque is much tighter than the original factory torque. Also you must use a special sealer in the anti- freeze to seal any porosity in the block. I made these modifications At 94,000 miles and I know have 126,000 Miles and have not had any problems with my engine. I change the oil every 3,000 miles.
I installed platinum+4 spark plugs, an Accel ignition Coil & wires, & a K&N air filter. This added quite a bit of horsepower.
Seems the common thread of these engines is a hit or miss thing. I've known guys who, with excellent maintenance, never got more than 70,000 miles out of their engine, and some that went through several new engines before that time. There have also been stories of people getting 200k+ miles out of these cars without so much as a new spark plug. I guess the HT4100 truly exemplifies the old Latin phrase "Caveat Emptor" -- Buyer Beware!
I can't give up my 82 Sedan DeVille! Yes it is big and people are surprised at how well I can maneuver that barge. I just replaced the high-pressure hose on the power steering unit. Now I am trying to find the dang cable that plugs into the circuit board and plugs into the CB unit. Of course it is not on any schematics because it was the AM/FM, Cassette, CB model. But I cannot sell her no matter what my wife says. Everytime it breaks something the usual conversation is "We need to sell that damn thing." As you said before I would rather put money into repairing it than a car payment. Next major expense is the paint job. Motor leaks at the main seal, but I just need to find a mechanic to replace that for me.
I am considering purchasing a 1984 Caddy with a sick 4100. I have owned a previous 84 with the same engine and it has over 90k on the odomoter. Had to rebuild transmission, but my brother did that in his barn, and it seems to be working. The high mileage 4100 is a result of using the proper sealant in the coolant. Cadillac was right about this requirement. It truely is a gigantic barge and slowly finds its way to the speed limit, but my grandsons can streach out in the back seat and feel as if they were in a leather swimming pool. It is axiomatic thatif it is a Cadillac, it will break. Look at all the newer ones that have water in the rear taillight lenses. See if you can find an older one with a working radio or trip computer. They are all true barnicle encrusted whales with incredible comfort. And the way they porpoise down the highway is breathtaking.