Small Engine Troubleshooting Problems? Ask a Mechanic Now.
So it shuts off when pto is engaged. Safety switch for seat, brake or pto. The mower thinks that no one is in the seat, so when the pto is engaged, it kills the engine. The mower has two circuits through the safety switches, one is for start, it is ok. The other is for run, it is not complete. Check the seat switch and harness first, then the brake switch.
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