I bought a 95 Buick Century,that ran like a champ?

Question

I flushed the radiator and added 2 gallons of prestone antifreeze in it, then all of a sudden I start to run hot for about 2 straight weeks constantantly adding prestone anti-freeze my coolant needle was in and out of the overheating range and every time I would check my radiator the antifreeze would be low as if it was dissappearing so I kept on adding this reagular prestone antifreeze into my radiator when I noticed a label on top of my radiator that read"This vehical takes Dex-cool antifree" so I instantly added 2 gallons of Dex-cool antifreeze into my radiator with the engine running and the heater on, ten minutes later thick white smoke start to come out the exhaust and out the engine so I took it to the shop and it was a blown heads and water in the block my question is was the reagular prestone anti freeze was the reason my car was running hot? and will I be better off buying a rebuilt engine or replacing the heads?

Answer 1

Dexcool and regular Prestone are not compatible. Unless you drained and flushed the block and heater core along with the radiator, any residual Dexcool may have combined and reacted with the Prestone and clogged your cooling passages, thus leading to your overheating.

However, if the overheating and coolant loss began immediately after flushing and refilling the radiator, I would bet that the previous owner had problems and simply added some "miracle in a bottle" sealer to the antifreeze instead of performing correct repairs. When you flushed the radiator, the sealer was removed and the problems returned.

As to whether or not you should replace the heads or the whole engine: that's hard to say. It depends on the overall condition and mileage of car, plus how much you like the car and how long you want to keep it. If you don't plan on keeping the car a long time, expensive repairs don't make sense, especially considering the age of the car.

Fortunately, the engine may be fine if it only had antifreeze in the crankcase a short time, and wasn't damaged by overheating. Change the contaminated oil, then change it again in about 1000 miles, and again in another 1000 miles.

If you decide to go ahead with repairs and keep the car, consider changing the transmission fluid, too. Many people will advise against this, but transmission fluid deteriorates rapidly when overheated, and can contribute to transmission failure if not changed.

Answer 2

Sounds like you had an air pocket in the cooling system after the flush, and overheating the engine did not help the head gaskets, it did not matter what type of coolant, running the engine hot due to an air pocket not allowing the coolant to circulate properly is what did your engine in. If you drove it with coolant in the oil, you are better off with a replacement engine, bearing damage has already occured.

Answer 3

i own a repair shop,and anti freeze wont cause one to blow a head gasket,if you don't have nothing in it it will blow a head gasket,but changing it didn't cause it to do that,i think it might have had a problem before,and it might have had stop leak in it to prevent it from doing this,and once you flushed it out you got rid of the stop leak,and that's probably started it to do this,id have it checked real good before i spent any money on this engine,it might be shot,but a real good mechanic can tell you for sure,good luck i hope this help,s.

Answer 4

you got a head gasket leaking.hows the engine run?if it runs good then all you need is change thehead gaskets(make sure you change both gaskets,and if you want to do a good job,take it to a machine shop and have the heads shaved for straightness.

Answer 5

what does fuel gauge say and are you for sure you filled up with right type of fuel ,like gas and diesel don't mix is there any thing else it did before dying

Answer 6

intake leaking internally
intermix of coolant and oil damages the engine.
replace it

Answer 7

did you check the over flow also?