testing Viscous fans

That's normal - it should settle down after 30 seconds or so.

On or around Tue, 19 Dec 2006 13:35:16 +1300, EMB enlightened us thusly:

you should be able to hear it slow down, as EMB says in about 30 seconds, revving to 2-3000 should result in engine noise but no fan noise to speak of. Try running it with the bonnet up, let it run for a bit and then rev it to see if the fan slows down. If you get big roary fan noise even when it's been running for say a minute, it might be seized.

Thanks Both

Probably seized then! But I'll try the test as suggested.

My bloke wot spanners the RR suggests that one (i.e. someone else!) can grip the tip of the blade before starting the engine and that this is sufficient to stop the fan spinning when cold!!! Any volunteers?

OK so assuming it is seized, what are the pros and cons of replacing it with the twin fan Kenlowe unit fitted in my 3.5 RR (this one is a 3.9). I have the viscous fan etc that I removed from the 3.5

TIA

Richard

On or around Tue, 19 Dec 2006 20:38:48 +0000, Richard enlightened us thusly:

safer bet is to try to turn the fan with the engine stationary...

Richard uttered summat worrerz funny about:

Having had electric fans in the past... bugger all difference.

Lee D

Hi Lee

That was my conclusion. But an available working pair of Kenlowes is an attractive solution to forking out for a replacement viscous fan. Also (don't laugh) I can't remember how to change alternator etc belts on a viscous fan-equipped vehicle - looks a right trial!

The original reason for asking was a vague memory of the dual function rads having a tendency to split in the most disastrous manner contaminating gearbox with engine coolannt - they cool the engine and the auto transmission, that's right isn't it?, and I wondered if the infrequent chilling effect of the Kenlowes would stress the rad more than was sensible - when compared with the gentle coolng of the viscous unit.

Cheers

Richard

On or around Tue, 19 Dec 2006 20:38:48 +0000, Richard enlightened us thusly:

Personally I like the viscous fans. I have got a kenlowe on the transit but that's cos the vicsous fan is missing, some pillock in the past has broken the hub/thread for it, also, the transit being a TDi rarely gets hot enough to need it.

I've had electric fans (not kenlowe, admittedly) fail and not run when needed, and while it's true that the viscous ones can fail "free" it's unusual IME.

That's why some people call them vicious fans. :-)

Martin

hi ,

In this weather , mine freewheels for about 3 - 4 seconds when you turn the engine off.

HTH , Wafty