OverHeating Issue

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Bostn635csi
Posts: 56
Joined: Thu Jun 19, 2014 11:40 pm
Location: Boston

OverHeating Issue

Post by Bostn635csi »

Hello
Having some overheating issues. Seems to happen when in heavy traffic. As soon as I get some air to the front of the car the temp goes back to normal. Mechanic replace clutch fan as well as thermostat. Temp is still a bit high when the car sits and idles. Never reaches the red. Could it be the head gasket? Any advice is appreciated. Thanks.
Kevin
1988 BMW 635csi, 5-speed
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hornhospital
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Re: OverHeating Issue

Post by hornhospital »

Your fan clutch is failing. Overheating when stopped is a sure sign it's not pulling enough air through. It 'locks up' (not really, but it engages more firmly) when the temperature goes up, and free-wheels when it goes down such as when you have air moving through the radiator at road speeds. When they fail they free-wheel all the time.
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
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Brucey
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Re: OverHeating Issue

Post by Brucey »

635CSi usually has a two-speed electric fan as well as a viscous fan. Probably (even if the viscous fan is OK) the electric fan should help out and it isn't kicking in at the right time, or at all.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
vietrice4ever
Posts: 9
Joined: Tue Feb 21, 2017 9:42 pm
Location: San Diego, CA

Re: OverHeating Issue

Post by vietrice4ever »

Hi Bostn635csi,
Hope your problem fix. I been having same problem, I don't know what to do. I changed radiator, water pump, fan clutch and thermostat twice. freeway driving without any problem only locally streets.

Please let me know how did you get it resolve.


Thanks
glenns0245
Posts: 18
Joined: Tue Sep 06, 2016 3:36 pm
Location: Venice, CA

Re: OverHeating Issue

Post by glenns0245 »

Im having the same issue. After testing my aux fan and finding it works well Im moving on check the aux fan switch. Thinking that the aux fan isnt kicking on.
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