URS4 visco fan failure - replace or mod?

[Bambi]

My visco coupling on my URS4 is goners. What now. Do I replace or rather take it off and fit electric fan next to the aircon fan. I've seen URS4's without the visco fan and nothing else, but I do not think it's a good idea. To check I held the Visco fan still with a cable and let her idle to see if the aircon fan would start cycling in and out, but my nerves falied by the tine the needle reached the first line past "normal" on the water temp gauge - nothing happened.?!? Maybe fan switch ******ed? how do I check - and incidentely, I didn't hear the afterrun pump come on (or does it only come on after a while?)

[S2central.net]

I would just repair the viscous fan to be honest... Less stressful than looming in an aftermarket electrical fan.

The cooling system of the AAN is designed to run with the visco fan so it best kept that way. Its a pretty reliable part, but like all things has a lifetime.

I can't remember if the AAN has an auxiliary elecrical fan for periods of high temperature but if you wish to test it - then simply short the high-temp switch pins to bypass the sensor that is on the radiator. If all the electrics are OK then the fan should come on.

Afterrun fan mode is another matter. A different temp switch on the water rail controls that one - you can also short that one manually to test the fan comes on - this should work within about 15minutes after turning off the engine... After that, the afterrun controller turns off the feed. Remember this is a switched +12V signal - not a switched earth !

Paul

[Bambi]

Thanx!

[topsparky]

i'm sure its the same part no as the a8,rs4
part no 078 121 350 a
also 078 121 350 d