Overheating

[uginer]

Well, Im driving down the road and everything is just fine. I stoped at the wendys drive through and noticed taht my temp guage was at red. I shut the car off. Started driving again and most of the time if im going fast enough the car keeps cool, but if i stop it starts to heat again. When i got home i raised the hood and hears masive bubbling noises coming from the coolent overflow tank. The coolent sounded like it was boiling in there. The pressure was crazzy.

- the fan clutch is new.
- Never changed the termastat
- never changed the water pump

I hope that it isnt the head guasket, what do you guys think?

[blackpawn5]

Well i had the same problem.
In my particular case, the switch to the clutch fan was failing.
Also my water pump was bad, which then lead to my radiator springing a leak. I had to have everything replaced which ran about $600. my guess is the fan clutch switch or water pump failure!

[bissellh]

You will need a new radiator, water pump or thermostat or all three. Inspect your radiator. The way you can tell if coolant is being pumped through the engine is too squeeze the hoses between the engine and radiator after the engine heats up to normal temperature. When the engine is cool they are easy to squeeze with only air in them. When the engine warms up the temperature switch activates so coolant is pumped through the hoses. To be honest, I do not know if the temperature switch activates the water pump or if it simple opens a valve allowing the water to pump to move the coolant along. Either way I suppose it does not matter much. You should be able to feel the pressure and heat of hot coolant being pumped through the hoses. If you can't, either the switch or the pump need replacement. I would start with the switch because it is an easier repair. I did it recently on BMW at the same time I replaced the radiator. I put in a low temperature thermostat to run my engine cooler. I does not sound like you did any damage to the engine. Bottom line is the cooling system is not rocket science, but the components require rather frequent replacement.

[Fahad]

- the fan clutch is new.
- Never changed the termastat
- never changed the water pump



if you never changed them you better do now.they are known to fail on BMWs and must be checked every now and then.

If you can, change raditor, water pump, thermostat, therostat housing and upper and lower hoses..
these parts seem to be regular tear items on bimmers

all the best

[uginer]

Ill replace all those things, its time to do so anyway.