The timer knob for my Viking (Canadian Model, think mfr is GE) refuses to rotate when setting the timer. In fact I stripped the knob trying to turn it! I took the timer out (part#: WH12X935) applied more force and again tried to move it, but it would not budge. I then removed the timer motor. Now the timer rotates. It seems the motor was preventing it from rotating. The motor shaft will not rotate by hand. Is the motor defective or is there something wrong with the gearing inside the timer? In a normally functioning timer you hear a clicking sound when rotating the timer. Is this some sort of built in clutch which has failed in my unit?

Thanks for the reply. Upon further examination I found that there is a split gear with two halves that mesh together. This allows the timer knob to be rotated when setting the cycle without forcing the timer motor to rotate. In my case this was jammed. I sprayed some WD40 between the gears and this seems to have flushed out whatever was causing it to stick..... at least for now. I still have to eventually get a replacement knob, but for now I can get the machine to work. It seems that replacing the timer is not an option as they are no longer made.