My friends used 92 325 keeps overheating, so last weekend we decided to go ahead a replace the waterpump and thermostat. But to my surprise the waterpump was the metal impeller one so that could be the cause, could it??
Also he had gone to a mechanic to replace the thermostat earlier so that can't be it either(although not sure about the thermostat he bought and had put it in, it is stamped with 176 degrees not sure what that means tho).
Neways I checked the radiator and the hoses and everything was leak-free. So why the hell is his car still overheating?? Neone have ne ideas??

One thing of note is that his heat doesn't work in the car about the same time that the car started to overheat. He probably needs to have the heater core replaced, but would this cause the overheating??

Ne thing you guys can think of would be greatly appreciated, especially since me and my friend has been trying to look for the problem all last weekend and couldn't. It wouldn't have been a problem either if it weren't so damn cold out there. Plus almost every screw and bolt on that car is rusted and seized up, and the more time we spend working on the car the more problems we find. Currently the sparkplug holes are filled with oil, indicating the valve gasket needs changing and the power steering fluid is leaking from somewhere.

I know my friend bought a lemon but buying a used car with 150k on the odo with no service record, your kinda askin for trouble.

Thanks

Wes

Pretty sure the system ahsn't been bled properly.
Owing to what you have already done as far as replacements, I would start the car,turn on heater full ( this is one place air likes to hide), open the bleed screw on radiator and massage the hoses.

Do the above with the engine at or about ormal operating temp.
The air will expand and go to the lowest pressure point.
In this case, the bleed as it is at 1 atmosphere.
:)

I tried bleeding the system before starting work on the car and it still overheat. Does it matter when bleeding the air from the cooling system if there is something wrong with the heater core(heat was not functioning properly)?

another thing I noticed is that a noise was coming from the radiator cap area and it sounded like it was suckin air into the radiator expansion tank, so we bought a new one and replaced it and rebleed the system and it was still overheating.

Also is there ne signs if a thermostat is broken?? I wanna see if his old thermostat was broken and the replacement he bought just had the wrong temp rating, and thats y his car still overheats

Seriously, it is probably air in the system. It can take days to get an air bubble to pass. It helps if you drill about 4 1/4" holes around the top of the thermostat if you pull it to inspect. The foolproof way to bleed is to elevate the front of the car and massage the top rad hose while opening/closing the bleed screw. Open screw, squeeze hose, close screw, release hose - like bleeding brakes. Your system should hold about 1.5-2 gal.

176F is roughly the same as 88C, so the thermostat temp is fine. Since your not getting heat, I'd also say that you've got air in the cooling system somewhere. Most likely the mechanic that installed the thermostat didn't bleed the air properly.

BTW, don't get the engine up to temp before opening the bleeder screw and the cap, open them when the engine is still cool or you'll end up getting sprayed in the face with hot coolant.

I'm thinking air lock.. thats what was wrong with mines.. good luck

if overheating was not occuring before mechanic's initial replacement of thermostat, then likely overheating now is because of remnant air pockets.

the first time i replaced my bimmer radiator, i had a massive air pocket in system. since i really hate watching my temperature gauge go above normal, i shut off engine letting it cool. then i disconnected upper radiator hose at radiator and filled both to spill point and reconnected. started engine, bled a little and finished with minimal topping off. have done this routine twice since and is is very fast and efficient way to finish job. can recomment in difficult fill and bleeds sitiuations.

i too would like to know if turning on heater when heater core is clogged could impede flow and cause overheating. perhaps someone knowlegable can weigh in on this question.

make sure your auxillary fan works as it should.

Im taking an automotive class and a lady came in and said that her car was overheating. I forgot why, but the reason her car was overheating was because her radiator cap wasn't strong enough to hold the water in at high temps so the thermostat never got to read the water the right way, I think. Try changing the radiator cap to one that withstands higher pressure, or a new one that holds the same amount. anyway, good luck.:)

Sounds like you might need to drain whole system (including block-drain is behind exhaust manifold) and start over. I've heard bubbles/air locks can be a bitch to get out.

Well I have a similar problem... sounds quite a bit like what's happening here. Here's the scenario:

1) Heat doesn't work at first.
2) Car starts to overheat.
3) Strange smell comes through vents
4) After the smell, heat works and the temperature falls back to normal and stays there.

Is there some valve that's getting stuck and then suddenly opening? It doesn't seem like an air pocket because I can consistently tell when the heat is about to start working because of the subtle smell that comes directly before. It *is* worrisome - plus I'd like my heat to work.

Any ideas? Side note: I'm losing an entire resevoir of coolant per week, yet I can't find a leak...... Sometimes I hate cars.

-chicken

That smell might be the coolant as it evaporates from your exhaust manifold.
Indicating a leak somewhere as it's consistent with your loss of coolant from the reservoir.
Must be a slow one since you can't detect by observing a drip, but if not a heater core leak (i seriously doubt it would be), then
Your head gasket is leaking or a hose has a small leak or a crack somewhere on the palstic tank(s).

See any oil in coolant? white gunk on oil filler cap?
Any drivability probs?