viscous question

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aze30
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Post Wed Jun 17, 2015 10:00 am

The viscous fan kicks in on my car after around 5 mins of driving.
the temp guage always sits just above the first quarter.
does this mean my viscous is faulty?
i didnt notice this before i parked it up.
Car has been stood for 4 years mind.
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BHadley
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Post Wed Jun 17, 2015 1:22 pm

Viscous fan clutches are faulty when the car tempreture rises when at idle or when in traffic for example.
jmc330i
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Post Wed Jun 17, 2015 2:19 pm

What makes you say the fan is kicking?

The viscous coupling shouldn't lock up whilst driving as the air flow through the rad while the car is moving should be enough to keep things cool, so the fan will just be free wheeling. If the car is stationary or slow moving, in stop start traffic for example, the temp rise will lock the vicious coupling and the fan will do its job.
James
'91 325i Sport
'93 318i touring 16v
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aze30
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Post Wed Jun 17, 2015 11:58 pm

jmc330i wrote:What makes you say the fan is kicking?

The viscous coupling shouldn't lock up whilst driving as the air flow through the rad while the car is moving should be enough to keep things cool, so the fan will just be free wheeling. If the car is stationary or slow moving, in stop start traffic for example, the temp rise will lock the vicious coupling and the fan will do its job.
cool i think its faulty then.
the viscous seems to be consistantly locked as soon as the engine reaches operating temperature.
it always sounds like vacuum sound like a deep sucking noise.

my old 325i didnt do this at all and you could always just hear the great rasp of that 6cyl soundtrack.