Hi, my name isXXXXX am eager to help you solve your appliance problems. When you mount the motor do you have to loosen the lift arm to fit it in?
No the lift arm is swinging freely. I lift it slightly to get it lined up with the rotating arm on the motor.
The rotating arm on the motor is missing the switch's when it is under load of the vent hood. Verify that the arm makes definitive contact to the switch's.
I can not see the switches when the arm is under load, but I checked with the ohmeter on the leads to the switch and it does not appear to be closing.
Peter, I may have misunderstood your answer, but at least you were close. As I read your suggestion about the "drive arm", I thought you were talking about the straight link that lifts the hood. This is not bent or loose. And I can disconnect it and the problem is not resolved.
But after taking the drive assembly out and reinstalling several times, I realized that the switches are making contact reliably when the unit is lying on its back, but not when it is vertical. It does not matter whether the lift arm is connected. This may be due to wear in the gear reducer bearings, which may be what you were referring to as the "drive arm", but it is cetainly true that replacing either any f the arms or linkages would not have corrected the problem.
To correct the problem, I filed the small oblong hole for the lower limit switch so it moves a little closer to the cam. Works OK now.
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