QuestionI have a 1997 BMW 328i. A month ago, I replaced the radiator. A day later, it was overheating. I topped up the coolant level and managed to drive home.
The following morning, I took it to the garage where they replaced the fan clutch and the thermostart.
After that, it never overheated. BUt I have to replace coolant EVERY MORNING. The car is not leaking but it finishes coolant very quickly.
What might be the problem and how can I solve the problem?
Answerhello,
The obvious question is where is the coolant going?
Check the engine bay for signs of coolant leaks, it should appear as a white chalky residue. Remember to look around the heater pipes where they go into the front bulkhead/firewall, and check for signs of water leaking into the cabin as well.
My first thought would be to try one of the better Radiator leak stoppers like Bars Leaks or Radweld to see if that makes a difference.
If it doesn't and no leaks can be detected, you will have to assume that head gasket failure (due to the initial overheating problem) is the culprit. This can be detected by any good garage with a chemical test to determine if any Co2 is present in the coolant.
You dont say how hot the car got when it overheated after the radiator was replaced, and this could be critical in determining if head damage is likely. Remember when replacing a radiator to bleed the system completely as airlocks can cause overheating.
You can also check if you are getting back pressure through the expansion tank/ radiator reservior, with the car idling
at operating temperature, does the coolant in the tank bubble and boil? This is usually an indication of head gasket failure as the engine pressurises the water system.
Let me know if you have any luck.
Regards
Rob
