Hi
I have an e36 323i 2.5l coupe 1997 model.
My problem is that if I drive the car above 4000 rpm the temperature  goes high in to red.
When I drive less than this usally not more than 3000 rpm everything is ok and the temperature is bang in the middle.I have changed the thermostat and radiator,new coolant and is still doing it.Could it be the water pump or head casket?Any help will be appreciated.

In this case,I certainly sure that your water pump and head gasket should be change because you already has a thermostat and new radiator or your car will demage if you still drive it.Hope this can solve your problem..ok see u

after changing those parts, do you still add coolant frequently?

do you hear irritating noises (whistling high pitch sound)on the engine?

no visisble leaks?

belt not over tight, loose or worn?

what test have you done lately? did you or they pressure test the cooling system?

do you see a cloud of white smoke coming out the exhaust?


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W I N D Z
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Hi.Thanks for your reply.I am not adding water and there is no leaks.No noises at all.The engine runs smooth with no signs of water in the oil or oil in the water.Belt seeems ok.They did a pressure test everything ok.The said no gas signs in the radiator.And no cloud coming out of the exhaust at all.It's sound very strange to me.Could it be a not working properly watwr pump?

goodluck and hope you will find the culprit. i'm curious about your problem and thinking that maybe your mechanic overlooked something very important.

please give us update here. thanks


_________________
W I N D Z
" Once is enough, Twice is too much, Thrice is a disaster. "

www.M-BenzForum.com

the way i check the pump is to remove it and inspect mechanically. check it's bearing, any movement or a rough or grinding as the bearing is turned indicates defective water pump.

the engine may overheat for reasons unrelated to the cooling system. possible causes include high-altitude operation, low oil level, engine overload, hot-climate operation and long periods of slow speed or idling.


_________________
W I N D Z
" Once is enough, Twice is too much, Thrice is a disaster. "

www.M-BenzForum.com

O.K Thanks for your help.I'll check the water pump today and let you know of the result.

Good morning.Water pump checked and is fine.Took it up to 5000 rpm yesterday and was ok.Is it normal when the car is hot for the hooses to be expanded and be a bit hard to press?

yeah because coolant is flowing through it when it reaches the threshold temperature. unlike when on a cold start, pressing this hose is softer because no coolant flows indicating that the thermostat is working.

i really can't explain what happened that it suddenly goes back to normal cause i don't have the chance to feel and see your vehicle.

hope she'll be doing fine now for good.

thanks for posting here...


_________________
W I N D Z
" Once is enough, Twice is too much, Thrice is a disaster. "

www.M-BenzForum.com

Thanks for your time and advice.I'll keep you informed for any developments.Thanks again