How Do I Troubleshoot a 12.5 HP Craftsman Mower That Stalls and Won't Restart Until Cool?
- 1). Park the lawn mower on a hard, level surface. Set the parking brake and ensure the machine is in neutral. Start the engine; let the engine run for 15 minutes and shut off the engine. Try to restart the engine; if it will not restart, proceed to the next step. If it starts, repeat this step until the engine will not start.
- 2). Remove the fuel cap and try to restart the mower. If the lawn mower starts, replace the fuel cap. If the machine does not start, proceed to the next step.
- 3). Open the hood of the lawn mower. Remove the spark plug wire located at the front of the engine. Plug the spark tester into the spark plug wire. Attach the other lead from the spark tester to the spark plug. Adjust the gap on the tester to 4.2 mm (0.166 inch) by turning the screw on top of the spark tester.
- 4). Turn the ignition key until the engine turns over. Watch the spark tester. If the spark is weak, erratic or there is no spark at all, the coil has malfunctioned and needs replacement.
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