No grounding involved anywhere in the cut-off (see diagram). Check that the wiring inside the cut-off is not shorted to the cover or case. There is/are points or relay inside the cut-out cover that open and close. Maybe the contacts are bad and arcing across?
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
