Just bought an 88 RS with a 2.8. The previous owner said someone told her a head gasket was bad, and that's why she was seeing steam from the exhaust. I have yet to see any steam. It does in fact over heat very rapidly, in about 5 minutes, its up over 225. I did also discover the radiator is leaking, which I will replace. I also thought about the thermo just being stuck shut. I want to go through all the simple possibilities before I get seriously into turning wrenches. For now, the V6 is staying in there. It is a five speed manual. We are not interested in a swap at this point. And from what Ive read its easier to just buy a V8 car to start with.

 

Check the oil very well to make sure no coolent is mixing in. Even pull the plugs if you wana double check things.

Do you know for sure that the radiator is leaking and where it's leaking at?

Does it fire up and idle well?

We'll I would pull the tstat out and inspect it or just replace it as they are cheep. Replace the radiator that is leaking then see if the over heating issue goes away.

Also when filling it up be sure to let the system burp. Once the tstat opens when it gets up to temp you will see that the radiator level will fall down fast and the air in the system will burp out. When filling leave the cap off and use a big funnel to fill it up and leave funnel In rad with water in it until it burps and then fill it up. When water stats coming out of the rad after it burped you can then toss the cap back on.

Don't rely on that temp guage to the exact temp. Those things are close to right but if the cars stock and such. It should level out to be about straight up and down on the guage when warmed up and not bounce arround (temps should stay steady).

 

The oil is okay...not milky. Thats one of the 1st things I checked. I went and bought a thermostat, then realized I needed a swivel, which I didnt have, but now do. That housing is in a really poor place IMO. The radiator is leaking on the passenger side, and bleeds out fairly quickly. Needs a new one. It idles fair. Runs and drives, gets up to speed, but the temp rises fast. It got so hot the day I brought it home, it barely had power to back into the driveway. That aint good. But Im gonna go in there today and do the thermostat and see where Im at. In case I need it, is there a place to find reman heads? I looked on Jegs and Summit, plus a couple others...couldnt find anything for a 2.8.

 

First , repair ALL external coolant leaks .

Then , do a "cooling system pressure test" . The tool required can usually be borrowed free* from most autoparts stores . This test will tell you if your actually leaking coolant into a cylinder from a bad head gasket or not .

Just for kicks , although it won't tell you much about this particular problem , a cylinder compression check will give a great deal of information of the condition of this new to you engine that you really have no history on .


*free being you usually leave a deposit that gets returned when you bring the tool back ...............

 

Why would you want remanufactured heads? Even if they were warped from overheating, you could just have them checked and decked at a machine shop for a lot less money then buying newer reman ones or going to a junkyard and taking the time to take them off hoping they are okay.

How hot did you get the engine and how many times? Durration?

Fix the coolent system first though.

 

I got home and removed the thermo that was already in the car. (would like to slap the GM engineer who designed the water neck location)...anyway.... I took that thermo into the kitchen and boiled it. It barely even opened. I took the new thermo from the box and boiled it as well...WIDE OPEN. So, I went and installed it. Filled the radiator with straight water....fired it off.. Watched the gauge. And to my surprise and pleasure it it went up to 195, and relaxed back down...went up again...went down...I ran the motor for about ten minutes. The cycle repeated. Now, I will put in a new radiator, flush the engine, and put in new anti-freeze. I think I have found the $5 problem. The engine has been hot a few times. Not gonna lie. The girl I bought it from drove it like this across town several times. But still have yet to see the steam and white smoke she was talking about.

 

get your cooling system flushed before you replace the radiator, helps getting all the crap out of the cooling system and will let the flow of antifreeze go better