HT4100 4.1, 4.5, 4.9 Discussion, HT4100 Check In in Cadillac Engine Technical Discussion; If you drive an HT4100 powered cadillac, post pics, reliability, when/how many problems you had, and how many times something ...
Something tells me you're gonna have a hard time giving that thing away. If someone had a free factory rebuilt HT 4100 I'd be hesitant about taking it. If/when mine goes it's Olds 350 time.
Right now it's being used as a model for the exhaust setup for my turbocharger project. The exhaust manifold patterns are the same on the heads. It's kind of an out-of-car model for the engine that's in the car now so I can get a decent idea of the welds and all...
there is another option you could always get a 4.5 tbi engine and swap crank liners heads and manifolds or get really creative at a machine shop and do the same guts swap with a 4.9 and use an after market controller for the pfi it would be unique and look really close to stock.
hey it's an idea
1987 Deville, HT-4100, 50,990 miles. Runs fine, no issues.
At 19,000, A/C stopped working, repaired at 43,000 after compressor seized. $940
At 36,000, lost the intake gaskets. $650
At 46,000, replaced alternator $150
The lady who owned the car before me never had the antifreeze changed until the intake gaskets were replaced. Other than routine maintenance and tuneups, that's it for expensive issues in almost 20 years.
I own a 1986 Coupe Deville with the 4.1 .This was a family car that my father-in-law purchased new. I have driven this car when it was new a few times, it has been passed down to me after it was worn out. I have replaced the brakes, shocks, drive axles and rack & pinion, because they were OE that's about 18 years all oe. that isn't so bad. the engine was well maintained over the years.
at 134,00 miles I just finished replacing the intake gasket, and it's running very smooth.
I love Caddy's I have owned several over the years but this one is special and I am keeping it to pass down to my daughter.
I have all the paperwork and repair manuals for the 4.1, its not really a bad engine, like all engines it needs to be maintained. there are special things these engine require, like the coolant tablets. don't let anyone tell you that you don't need them. they are important. don't skimp on cheap gaskets buy the best do the job once God knows it takes hard work to replace them.
Automobile(s): 1985 Cadillac Fleetwood Brougham d'elegance - 1969 Coupe DV
Santa Cruz, CA
Re: HT4100 Check In
i have an 85 fleetwood with 106,xxx miles on it. original engine, original transmission, original paint, original everything. nothing (except minor things like wiper delay and parking lamps) has been replaced or rebuilt. i did add some flowmasters though . anyways I have never had a problem with the engine other than the lack of power...
recently i have noticed that once in a while i will hear a noise like someone is dragging their nails across a chalkboard coming from under the hood. usually right after i start the car on a cold start. has only happened twice and ive had the car for 4 months.
other than that, great car! just needs a better engine!
My first experience with a 4.1L was in an 87' Deville. That thing was the biggest piece of crap I have ever seen in my life. Ran fine on a couple test drives, the car looked great. The thing was possessed or something. I got so pissed off at that car I called a guy in the newspaper to get it out of the driveway. I thought about sticking a rag out of the gas tank and burning the thing to the ground.
Second 4.1L completely different story. 84' Eldorado looked like hell when I got and ran like a champ tell I sold it. Fluid changes, filters, a couple hoses, an ISC and it ran probably the best a 4.1L could ever run. Great car when done. Ironically the first generations where the ones I was told were real problematic. Wish I still had it but I did need the money.
Third one 84' Seville still have. Good for what it is. Nothing has had to be changed or messed with. Rarely drive it. Hard to after you have drove around in some of the more powerful Cadillacs. Really just wanted the body. May try to get crazy with it. Always loved that body. It is my favorite cadillac design of all time. At least the extrior.