overheating prob

[DANGEROUS DAVE]

my1991 535i overheated on the way home last night it does not seem to be the head gasket. any ideas ?

[Rigmaster]

We need a bit more history in order to help you dave. It could be a number of things- thermostat could be stuck, water pump could be gone, coolant could be low/empty.

Is this the first time you have had an overheating problem with this car? Why do you think it's not the head gasket?

Any other info you can provide will help us help you.

Bret.

[shogun]

Loss of coolant, thermostat, visco clutch.
So, you should check all these. That info is not enough.
Did you check the coolant?
Did it overheat when driving on highway or only in stop and go traffic, or both?
Where was the needle of the temp. gauge?
How long did you drive like that?
Any sights of coolant loss in engine room?

[Rodericb]

my1991 535i overheated on the way home last night it does not seem to be the head gasket. any ideas ?

Like the other guys stated, you have to give more information. I had an overheating problem recently that turned out to be the radiator.

[Mitch90535im]

Read through this thread Dave.

http://www.bimmer.info/forum/showthread.php?postid=49891#poststop

My problem turned out to be a clog in the line that runs from the radiator back to the overflow tank. All it took to correct the problem was detaching the line from the radiator, blow air into it, and like magic, my overheating problem was solved.

This was after:

Bleed, bleed, bleed, bleed..... (50 or so times)
Fan clutch replacement
Thermostat replacement
Purchased, (but didn't install) new water pump

My advise - Start with the cheap things first and work up from there.

[DANGEROUS DAVE]

the car had a new head gasket about 30,000 miles ago and the head skimed
no oil in water nothing on dip stick but oil. heater is working fine and the car still runs smooth and starts well. both top and bottom hoses get hot so dont think its the thermostat coul be water pump what do you think ?

[DANGEROUS DAVE]

Loss of coolant, thermostat, visco clutch.
So, you should check all these. That info is not enough.
Did you check the coolant?
Did it overheat when driving on highway or only in stop and go traffic, or both?
Where was the needle of the temp. gauge?
How long did you drive like that?
Any sights of coolant loss in engine room?
she overheated but not in the red and didnt boil up and did cool down when i pulled over quite quick (back to half way on gauge) and when i cheked the next day no loss of coolant ?

[DANGEROUS DAVE]

cheers guys will take on board what you have said and go and try to solve the problem will get back to you all.

[DANGEROUS DAVE]

Loss of coolant, thermostat, visco clutch.
So, you should check all these. That info is not enough.
Did you check the coolant?
Did it overheat when driving on highway or only in stop and go traffic, or both?
Where was the needle of the temp. gauge?
How long did you drive like that?
Any sights of coolant loss in engine room?
how do i check if the visco fan is knackerd ?

[Mitch90535im]

how do i check if the visco fan is knackerd ?

I was told that when the engine is running (hot) and you turn off the ignition, the fan should come to an abrupt stop, which apparently isn't 100% correct since mine continued to turn several revolutions, which led me to suspect it was bad and replace it, which it wasn't. So, to answer your question, I'm not sure.

[JonE]

When the fan clutch is working properly and your engine is fully heated up, you should feel significant amounts of air blowing around under the hood. When mine was bad, the fan turned alright, but didn't blow much air at all, it is quite a difference when you experience it. My bad fan clutch would "free-wheel" when the engine was shut off after warmed up, it just kept spinning for awhile. True, when the good fan clutch was installed and the engine was warmed up and I shut off the engine, that good fan clutch would abruptly stop the fan.
If it needs replacement, remember that large nut is reverse threaded (righty loosey, in this case).

[632 Regal]

If its hot out and the engine is hot such as having the AC on, when you accelerate it will sound like a school bus taking off when the fan is fully working. If no schoolbus sound then its fried.

[Mitch90535im]

If its hot out and the engine is hot such as having the AC on, when you accelerate it will sound like a school bus taking off when the fan is fully working. If no schoolbus sound then its fried.

I forgot about that one - that was another reason I first tried replacing my fan clutch (it didn't sound like a school bus). Maybe our buses are just louder in this part of the country.