Fan clutch fault?

[JDW3696]

Hello all
The fan on my car goes at full speed at all times. My understanding is that it should only get going on full speed when the cars engine is very hot.
The car has got Evans waterless coolant so can't overheat like a normal car would unless there isn't enough in it.
Does this sound like my fan clutch is knackered? Is there a way of fixing it or should I just replace it? What are peoples views on electric fans or shall I just stick to standard and replace the fan clutch if needs be.
Thanks again
Joe

[Clan]

Originally Posted by JDW3696

Hello all
The fan on my car goes at full speed at all times. My understanding is that it should only get going on full speed when the cars engine is very hot.
The car has got Evans waterless coolant so can't overheat like a normal car would unless there isn't enough in it.
Does this sound like my fan clutch is knackered? Is there a way of fixing it or should I just replace it? What are peoples views on electric fans or shall I just stick to standard and replace the fan clutch if needs be.
Thanks again
Joe

What car have you ? It defaults to fast if the sensors cant be interpreted ..

Evans is widely known as a con , It is extremely expensive and can be dangerous if your engine gets up to 180C without boiling ... Your cooling system is utterly adequate with normal Volvo coolant otherwise you have a fault that needs fixing of course ..

from what you say it sounds like it may have a mechanical viscous clutch fan . it should run full speed after you start from cold and then after some seconds should idle around quietly ..

[TonyS9]

The fan should only engage on a very hot day if you are stopped for a few minutes, it sounds like a bus when you go up the revs a bit.

I do know the evan coolant is not as conductive as water, so maybe the engine and rad is getting hotter. Still, I have used this with the standard fan on the track in my B230FT 360 and it doesn't engage that I notice (360 fan is 34 yrs old has similar coupling), it does get quite hot idling and at high speed, but just about keeps in it control.

You could try lubricating the centre where the spring is, but otherwise I would just replace it. A good used unit should be ok, I've never seen one fail.

Electric fans are apparently better in theory, but I don't think there is much difference in lost power to a viscous coupled, and in a moving car. There are some erroneuos comparative tests done on fixed engines measuring power loss but you can ignore them, they are not representative of a moving vehicle.

[Laird Scooby]

What Clan said ^^^^^

Dump that useless Evans stuff before it causes leaks left, right and centre and either use the correct Volvo ethylene glycol or an good aftermarket ethylene glycol antifreeze.

ON NO ACCOUNT WHATSOEVER USE OAT COOLANT!!!!!

As for your fan, try turning it by hand when cold, it shoudl turn fairly easily. With the engine hot, try turning it again, it should have more resistance to turning. If not, you probably need a new viscous clutch or would be better off converting to an electric fan. The electric fan is quiet unless it's running and makes the car a much more pleasant place to be, the engine warms up quicker and without the drag of the fan, is livelier too.

In this weather, unless you do either a lot of town driving or motorway immediately followed by town driving, you won't even need the cooling fan unless there is a problem with your cooling system.

[TonyS9]

Originally Posted by Clan

What car have you ? It defaults to fast if the sensors cant be interpreted ..

Evans is widely known as a con , It is extremely expensive and can be dangerous if your engine gets up to 180C without boiling ... Your cooling system is utterly adequate with normal Volvo coolant otherwise you have a fault that needs fixing of course ..

from what you say it sounds like it may have a mechanical viscous clutch fan . it should run full speed after you start from cold and then after some seconds should idle around quietly ..

I think its a bit unfair the describe it as a con, I tried both water and Evans in my 360 with B230FT. Water runs cooler but at more pressure that the 360 cooling system was designed for so I went back to Evans and engineered in some more cooling.

Evans last forever, doesn't corrode your engine and runs at lower pressure, you pays your money and makes your choice.

[Laird Scooby]

Originally Posted by TonyS9

I think its a bit unfair the describe it as a con, I tried both water and Evans in my 360 with B230FT. Water runs cooler but at more pressure that the 360 cooling system was designed for so I went back to Evans and engineered in some more cooling.

Evans last forever, doesn't corrode your engine and runs at lower pressure, you pays your money and makes your choice.

There are several threads on here with people running Evans in 7/9xx and having problems with leaks and overheating Tony. There have been many occasions of Evans causing problems, even with the new, allegedly improved version. Might be ok for racing but not for a road car.

[TonyS9]

Originally Posted by Laird Scooby

There are several threads on here with people running Evans in 7/9xx and having problems with leaks and overheating Tony. There have been many occasions of Evans causing problems, even with the new, allegedly improved version. Might be ok for racing but not for a road car.

Track use has higher requirements than road use, but to be fair with the expensive of the fluid I use standard water based cooling in the 940. In my case its more that its suitable for my modified 360.

I have hade leaks, HG failure and corrosion with water based in the 940, but the root cause was something other than than the fluid. It still leaks a little over months.

[JDW3696]

Thankyou for your advice. Thats interesting. I thought it was a bonus. Strangely enough it is leaking from the thermostat housing. Might replace it. I have the b230e. Will see how it turns at cold and hot but at the moment it's on all the time so might look down the electric fan route.
On running issues which some of you have kindly helped before it is still lumpy on idle. The garage gave back all the hc readings and emissions as spot on but said there is an air leak somewhere. Sprayed it around the intake and idle changed. I narrowed it down to what I believe is the thermal timer. I sprayed around there and engine idled smoother. I believe its the thermal sensor. Brown sensor with two leads going into it at the rear of the engine on the rhs under the intake manifold. Has a black boot covering it. Would this cause poor idle if it is faulty? Any ideas?
Thanks
Joe

[Laird Scooby]

Originally Posted by JDW3696

Thankyou for your advice. Thats interesting. I thought it was a bonus. Strangely enough it is leaking from the thermostat housing. Might replace it. I have the b230e. Will see how it turns at cold and hot but at the moment it's on all the time so might look down the electric fan route.
On running issues which some of you have kindly helped before it is still lumpy on idle. The garage gave back all the hc readings and emissions as spot on but said there is an air leak somewhere. Sprayed it around the intake and idle changed. I narrowed it down to what I believe is the thermal timer. I sprayed around there and engine idled smoother. I believe its the thermal sensor. Brown sensor with two leads going into it at the rear of the engine on the rhs under the intake manifold. Has a black boot covering it. Would this cause poor idle if it is faulty? Any ideas?
Thanks
Joe

What were the emissions figures they gave you?

[JDW3696]

Sorry. Can't remember now. A friend plugged it in as a favour this morning.
Should have asked.