The Rover-Landers of BC

Hi James,
Here is a snipet of the RRC Viscous Coupling being discussed on another web site. I can't say it is total accurate or not but it does seem to make sense! These things are normally bullet proof, are you sure this is your problem?
Andy

SM
"The viscous coupling passes drive from the rear output shaft to the
front output shaft. When the silicon fluid in the viscous
coupling becomes warm its resistance to shear
increases passing more drive to the front drive shaft
increasing traction."
Mick.

"If you just jack up one side of the car, both the wheels that are off the ground will spin and you will learn nothing. As one of the previous posts says, the fluid in the diff has to get hot in order to start locking it up. This is achieved when one axle is turning and the other is not (or there is a big difference in their speed). You could perhaps get this effect by jacking one side of the car then lightly applying the parking brake. If you then run the engine slowly in gear, first only the front wheel will turn. Then, as the diff begins to lock, it will overpower the brake and turn the rear wheel as well. I've never tried this, but it should work. However, the viscous diff is so simple that I do not think it will be prone to failure. "

I’m not an expert on the RRC, however your “center differentialâ€

I believe that it is normal to have no drive when the front shaft is off.

The viscous coupling is like an automatic diff lock. Unless your viscous coupling is seized solid (NOT GOOD, COMMON PROBLEM) the power will flow to the easiest way out. With the front driveshaft off, the easiest way out is to spin the front drive shaft flange.

I suppose with the rear wheels not moving and the front flange spinning one might get the viscous to lock up a little, but more likely will just kill it.

I don't think you have a problem there.

BTW, Haynes manuals are great for getting yourself into trouble!! :lol:

Later,
Don