visco fan always going

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crazycat
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visco fan always going

Post by crazycat » 17 Jun 2010 12:58 pm

The visco fan on my 360 starts rotating even when engine is cold,
engine doesn't really get warm, never reached half of the heat gauge even after 2 hours of driving and i heard that the fan takes up a few horses too

Is there a way to fix it or will i have to buy a new one? and will visco fans from 2/7/900s fit?

thanks in advance

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L14MNP
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Re: visco fan always going

Post by L14MNP » 17 Jun 2010 03:07 pm

It turns with the engine mate, so it's always running.

Yeah they steal a few ponies. Remove it and fit electric ones if you don't like it or want one that cuts in/out via thermostat.
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volvodspec
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Re: visco fan always going

Post by volvodspec » 17 Jun 2010 03:49 pm

viscofan isn't solid mounted unless it is broken...

with the engine off you should be able to rotate the fan by hand, untill the engine warms up then it makes a solid link and turns with the waterpump pulley.

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L14MNP
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Re: visco fan always going

Post by L14MNP » 17 Jun 2010 03:52 pm

Say what?

So you're saying the fan shouldn't rotate until the water is up to temperature?
Many cars with viscous fans turn constantly though. I thought these engines were the same. This is the first and only car I have personally owned that has one.

It may explain why it tried to take my (gloved) hand off when I attempted to stop it though. :lol: FYI I can turn it by hand with the engine off.

I am confused and of no help to this thread so I shall cease my contribution! lol
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volvodspec
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Re: visco fan always going

Post by volvodspec » 17 Jun 2010 04:04 pm

well it does allways turn with the engine running, but it won't fully work untill engine is up to temperature :D
best way to check if the viscocoupling is working is listed above

when the thing ages there is a chance the hydraulic fluid in the coupling leaks out and it becomes attached permanently; then it is broken.

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L14MNP
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Re: visco fan always going

Post by L14MNP » 17 Jun 2010 04:10 pm

I was confused.

Now I am educated.

many thanks sir. 340pw i can stop the thread jack now cos I am removing my (working version) anyway. :lol:
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crazycat
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Re: visco fan always going

Post by crazycat » 17 Jun 2010 04:11 pm

well so when i try to turn it when the engine is off and the belt turns too it is broken - because then theres a solid connection?

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volvodspec
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Re: visco fan always going

Post by volvodspec » 17 Jun 2010 07:36 pm

correct

but, even if the viscocoupling itself is "broken" this doesn't cause any harm. if you want the slight powerincrease you could indeed install an electric fan.
about the temperature issue; have you checked the thermostate?

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L14MNP
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Re: visco fan always going

Post by L14MNP » 17 Jun 2010 09:42 pm

I read up on this whilst watching Mexico pwn France earlier when I was tidying the garage. Who says men can't multitask? :lol:

I wondered why it only operated at max RPM when most needed, but noise and MPG are noted as the reasons for this. Makes sense!
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Ride_on
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Re: visco fan always going

Post by Ride_on » 17 Jun 2010 11:21 pm

A stuck fan coupling will not cause under heating, most likely your thermostat, they are a consumable, maybe only last 5 years. Make sure you get a proper 92C opening one, they are often 88C opening ones which won't help your heating and proper running, + the gauge sits annoyingly off centre.

I do hate the noise the fan makes at high RPM, although it should only make that bus noise when its very warm, maybe after idling in the summer traffic. Definitely noticed it on and off in the 940 depending on heat build up (mech fan only), once driving it should go off within a minute or so.
1980 345 DL_______1987 360 GLE (project car restored to GLT spec and B230FT'd)
1984 360 GLT______1987 360 GLT
1983 360 GLS______1989 360 GLE
1985 340 GL_______1986 340 1.4
1985 360 GLS______1995 940 SE 2.3 Turbo Estate (daily)
1987 340 GL 1.7

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