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Viscous noise

Posted: Thu Jul 18, 2013 7:33 am
by i8lufc
Hi All,

Heating and cooling working ok and temp not jumping in static traffic. But when engne is hot and I pull away from junctions I get an increasing viscous noise through the revs.

Any ideas please?

Mantra is always "if it isn't broke don't fix it - but I thnk something is gonna break!

Re: Viscous noise

Posted: Thu Jul 18, 2013 8:46 am
by jmc330i
That's the viscous fan working I'd say. The fan will be louder when its hot and the fan is actually working.

Re: Viscous noise

Posted: Thu Jul 18, 2013 8:52 am
by i8lufc
Thanks for the response JMC but over the past six weeks, it is a LOT louder than it ever used to be - never used to hear it before

Re: Viscous noise

Posted: Thu Jul 18, 2013 9:16 am
by Brianmoooore
If the car is getting hot enough to lock the viscous, it will take a short while for it to cool enough to unlock when you get into free moving traffic, but if it's staying locked, then either your cooling system is marginal and in need of an overhaul, or the centre bearing of the viscous is seizing.
How easy is it to turn the fan when the car is cold?

Re: Viscous noise

Posted: Thu Jul 18, 2013 10:07 am
by i8lufc
HI Brian

The fan turns without a lot of push for about a quarter before stopping. Bearing gone you reckon?

Cheers, shaun

Re: Viscous noise

Posted: Thu Jul 18, 2013 10:10 am
by Brianmoooore
It should turn with a bit of resistance, but should be smooth. If it comes to a halt, the bearing has failed.

Re: Viscous noise

Posted: Thu Jul 18, 2013 10:13 am
by i8lufc
Thanks Brian. Appreciated

Re: Viscous noise

Posted: Thu Jul 18, 2013 7:34 pm
by zd3bx
Mine makes a noise when revving too (OEM viscous coupling, only few months old). I don't think it's an issue, especially in this weather.

Re: Viscous noise

Posted: Thu Jul 18, 2013 8:09 pm
by Brianmoooore
New ones often are a bit noisy, until they loosen up a bit.

Re: Viscous noise

Posted: Thu Jul 18, 2013 10:03 pm
by Morat
Snigger :-)