HT4100 4.1, 4.5, 4.9 Discussion, 1991 Cadillac Biarittz - Engine problem. in Cadillac Engine Technical Discussion; Here's the story.
I bought this car back in November, it has 110-120 thousand miles on it, i don't remember ...
Here's the story.
I bought this car back in November, it has 110-120 thousand miles on it, i don't remember the exact number. When I first test drove it, it was fine(because it was only for about 10 minutes) then I had to take one of my pet's to the vet, and the engine pretty much started to overheat and wouldn't go over 40 mph uphill, the engine started smoking I'm pretty sure it was a white/grey smoke, I don't think it was black, but I couldn't really tell since it was about 11pm.
So I took my car to the garage, and the guy says that the engine is bad, he didn't tell me what all he tried, he basically said that there was 2 types of metals in the engine, I forget which two, and the way he explained it was; as the car runs from the gas heating up the one metal when it first ignites the gas by the time the gas goes through the engine its expanding and contrasting the one metal too much or something. I don't remember what he exactly said. Maybe someone else here can explain it better? The mechanic said that the cars year was just a "bad engine year", but then again, there is no official Cadillac garages around my area to look at it. But other than that, there is virtually nothing wrong with the car, except for cosmetics. I bought the car for about $800, and I found a place that can do a rebuild for about $1,500.
Now, I wouldn't mind spending that on a rebuild, but as the car sits I can't use it, and I wouldn't want to spend $1,500 on a rebuild if I can't use the car. I would be using it as my primary transportation vehicle.
Automobile(s): Cadillac 78 Seville, 78 Coupe de Ville, 92 Sedan de Ville
Re: 1991 Cadillac Biarittz - Engine problem.
Sounds bad, like it ran out of oil or coolant. Whenever you buy a car all fluids should be changed for peace of mind. It's probably not worth replacing the engine which would be cheaper than rebuilding one. Too bad because those were nice cars.
The mechanic was trying to explain that the 4.x series (pre-Northstar) uses different metals--aluminum block, steel heads, and aluminum intake--and they expand and contract at a different rate. During normal driving conditions this is not a problem but if the engine gets really hot several times then the gaskets will be scissored between the different metals. Now the car won't pull and was burning coolant, then the head gasket is probably shot. Unfortunately this condition can also cause the metal to become deformed and the engine has to be machined back to specifications. Plus the aluminum block can be hard to work with--sometimes the head bolts will strip the threads in the block. Once you're at this point it's just easier and faster to replace the whole engine.
It's up to you if you want to do it. They are interesting cars. The 4.9 engine in your 1991 is the best of the series, some of them go into 300k miles with no problems, and they are good reliable engines if they are maintained. I would do it if it were mine