Clutch type radiator fan always engaged.

[Z2TT]

Hi,

The radiator fan on my Soarer is always engaged, it will always spin even when the engine is cold. Tommorow I'm going to take it off and try to fix it. I've been gathering information so far I know that there is some sort of spring and fluid that expands with heat.

Has anybody had experiences with fixing these, fans. Any information will be useful.

Thankyou.

[RAAAH23]

my clutch is always engaged but maybe thats how they were in 1976.

maybe its the thermostat thats got some debris in it or just totally failed

[RA35GT]

Dood.

When cold is the clutch pretty solid? With engine off spin fan by hand, is there much resistance? if its pretty free then its fine.

if its pretty solid then its an issue.

They do not stop spinning when the engine is on.

When hot the fluid coupling becomes more solid and the fan spins harder. (i.e. like letting the clutch out in a car). With the engine stopped while hot the fan should move with more resistance. When running and you rev it you should notice the whoooshing noise more

[RAAAH23]

yeah thats what i thought, they never stop rotating they just dont rotate as much.

[petergoudie]

Take a close look because some of those fans can be locked up in an emergency meaning if they fail you can wind up a few bolts so they spin all the time so as to get you home.

Also, I think there is more than one set of bolt holes and its possible the fan is mounted on the wrong holes.

If you need one search ebay and the net because sometime back I saw some aftermarket ones that were relatively cheap.

[Vios-GT_07]

as far as i know the clutch fan has a special fluid in it that has a viscosity which reacts to temperature and rotating speed.. it's always spinning.. if it doesn't, it means it's failed..

there's nothing electrical in it.. so even if you took it apart it's more to refresh the fluid in it.. but most clutch fans i've come across are sealed units.. and when the clutch fails, electric fans are the cheaper and more effective option..

[andrew_mx83]

u should be able to stop the fan spinning with your hand whilst it is cold....as stated above they will always spin

[PeteH]

Hi,

The radiator fan on my Soarer is always engaged, it will always spin even when the engine is cold. Tommorow I'm going to take it off and try to fix it. I've been gathering information so far I know that there is some sort of spring and fluid that expands with heat.

Has anybody had experiences with fixing these, fans. Any information will be useful.

Thankyou.

Hi,

As everyone has already noted there is probably nothing wrong with your fan.

When cold and with the engine running the fan will still spin, although at a slower speed than the engine, as there is some drag with a viscous clutch . When the under bonnet temp reaches X, usually around 60 degrees, a bimetal strip activates a valve in the the clutch and the fan will then spin closer to engine speed. This valve usually has 4 stages and will go close to locked when the under bonnet temp reaches around 95 degrees. When this happens you will hear the loud whirring noise

The main reason to be looking at fixing the fan is if you start having overheating problems. Over time the fluid breaks down, or the sealed unit can leak, and the viscous fan becomes less effective.

When cold is the clutch pretty solid? With engine off spin fan by hand, is there much resistance? if its pretty free then its fine.

if its pretty solid then its an issue.

That's about right. There will be some resistance with a good viscous clutch with the engine off....there will be very little resistance with a dud viscous clutch, because the fluid has leaked or gone off......and yeah if it is solid with the engine off it is fooked, yet to see this though

Also, I think there is more than one set of bolt holes and its possible the fan is mounted on the wrong holes.

The four bolt holes are equally spaced. It can be remounted any old way.

and when the clutch fails, electric fans are the cheaper and more effective option..

Cheaper yes, more effective not by a long shot.

u should be able to stop the fan spinning with your hand whilst it is cold....as stated above they will always spin

Please don't try this . Use a rolled up length of newspaper if you want to give this a go. And in a good setup the drag on the clutch will have the fan trying to resist, that is it shouldn't be too easy to stop the fan it will take some effort with the newspaper...

Cheers,

Pete

[Z2TT]

Thanks everyone.

[87lux]

you can replace the fluid in the fan hub on some units and you can buy it from toyota. can't remember the part no.off the top of my head though.

[Moppitt]

When they're at the coldest 'setting' theyre (at least the ones i've dealt with) not hard to hold still with two fingers. That been said its a nicer way to go about it using rolled up newspaper.

[crownv8]

One simple way to see if it is working.

With the engine warmed right up, let it idle for a bit. Then bring the revs up to about 1500 and hold it there. You should hear the fan working quite hard and then after a few seconds it will slow down. If it is working good you can actually see the change in fan speed and you will also hear a change in fan noise.

If you fan is stuffed and fully locked it will be super noisy at high revs all the time.

Don't grab a spinning fan when it is dead cold though because they will lock a bit until the fluid settles down and don't grab it when its real hot if you like your fingers.

Cheers,
Shane.

[Z2TT]

Hi,

Today with the engine totally cold I turned the fan, it's not stuck it turns, but I cant well spin it, as in give it some force and it will keep spinning over and over. But I can move the blades without having to push or put force on it, but it does have resistance in the sense that if you try to spin the fan it will only spin like 1/4 of a turn before stopping.

I wasn't too keen about sticking things in the fan but tried out when the car was cold, Stuck a rolled up newspaper near it for half a second, didn't look like it was going to stop so I left it alone.

[RAAAH23]

yeah its def not going to spin like crazy 1/4 is about right doesnt seem like theres much wrong with it.

[Z2TT]

Thanks........