I have a 1990 535i e34. I just replaced the radiator and thermostatand now the car is overheating. Never had a problem with it overheating before changing rad./therm. I have bled out all the air; I think?? reason for replacing radiator was that it started leaking on the side. any suggestions?? I am going to pull the new thermostat and see if it is faulty.
You most likely need to replace your water pump. I had the same thing happen to me and was quite boggled that changing the radiator and thermostat did not fix the problem. Bud is also right, it is not a bad idea to replace your hoses.
These are quite tricky to bleed all the air from and it sounds like it is not bled completely yet.
Was the engine overheated when the radiator failed? If so it may have caused a problem with the head gasket which is causing overheating problems now?
My guess is that there is still air in the system (I had a lot of trouble with this the first time I did it so can understand your frustration). The way I do it now is to start the car with the coolant cap off and bring it up to temperature without the cap, adding coolant as the coolant level drops. Squeezing the hose from the water pump by hand gently as the engine warms up seems to help a lot. The small bleed line that enters the coolant reservoir should be giving a steady stream of water (no air bubbles) when all the air is gone.
Good luck with it and be careful, the heads on these engines do not like to be overheated and will make you pay if they are.
Thanks for the info everyone. I changed the thermostat and put in the old one and it runs a little cooler, but hotter than normal. I'll keep bleeding and bleeding. any suggestions or tricks to a successful bleeding??
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