Outer Limits 4x4 Board

Anyone know how to check the operation of their viscous fan?
When cold has slight resistence and will operate for about the first 20 seconds. Thereafter has minimal or no resistence up to normal operating temperature. How do I check it's operation for higher than normal operating temperature.

Suggest you find a hot day and drive in low ratio first or second for a while preferably up a hill.
If the temp moves up at all from the middle position, the viscous is stuffed and or the radiator blocked.
Mine stays rock steady at 39C.
regards Philip A

Guess that answers that then - I have and it does. It's not the radiator, warwe pump, or hoses cause they have all been replaced in the last month. Suspected the viscous but was wondering if there was any other way of testing them. How much resistence should it have when the engine starts getting warmer than normal?

if the engine is too warm, it should basically be locked, I would have said.

It locks on and off like switch. You'll hear it when it locks up.

a cheap way to fix it is to screw a big tec screw in to the hub and its locked perninantly

As long as you don't wade ever.

red90 wrote:As long as you don't wade ever.

isent that what fisherman do? it will throw the water arounf when wadeing but so will one in working order

No you run the risk of pulling the fan into the radiator. The fan is not designed to be strong enough to pump water.

If you lock the viscous you have a HIGH risk of throwing a blade or two as it is not designed to go over 2500-3000 RPM. The yellow plastic fans crack at the base of the blades at the best of times.
You will be very surprised at what a light plastic fan blade will do to a bonnet as it goes through, ditto radiator, battery etc.
Regards Philip A

I dont intend to lock the fan, and will stay with the viscous unit. Given an oe viscous is $$$, does anyone know of an aftermarket viscous fan or alternative that would suit?

Buy one from Paddocks in The UK. I have bought several things no problem.
Ask them to airmail, as this way no customs entry,, and no import duty or GST, if duty under $50 , which it is.

An idea but more expensive is to buy an ERR3366 200Tdi diesel viscous and fan. Far more efficient and quieter, but you have to buy the fan also so more expensive. The actual viscous is cheaper though.
This assumes LH thread on your viscous ie injection 3.5 or 3.9 with Vbelts ie up to 94.
I have one and very happy. friends in club told recent story where a club member with a 200Tdi fan died . They replaced with a V8 one they had in the group but it overheated all the time until they replaced the ERR3366.
regards Philip A

That should be ERR2266 and its for a 300Tdi and costs GBP 57.50 or about $180 landed.
regards Philip A

Thanks Philip. Will check them out. Mine has the serpentine belt however.