What is the fluid for the viscous fan clutch?

[4estjp]

I had to take my radiator in to get in cleaned and small leak soldered. The owner recommended taking the fan clutch apart and putting in new fluid. He thought I could use a Toyota product or an STP oil. Can the fan clutch be opened and what kind of fluid would work?

 

[sven]

Its sealed, you have to replace the whole part if its broken.

 

[Antichrist]

If it's a disco these fan clutches work.

Std Duty Imperial 215257
Hvy duty Imperial 215158

 

[4estjp]

One mate here bored the alu chamber from the fan clutch unit, inside one of the fixing screw holes.
He drained some quantity from this silicon compound, and refilled it with more quantity.
The bore was closed by replacing the mounting screw. He cleaned the bimetal spiral (thermostatic valvle sensor) and now the mounted fan seems to work properly.
In our market it seems that older toyotas have serviceable fan clutches, so this silicon compound seems to be available as spare part.