Generator starts then quickly shuts down with 'Overspeed' alarm; engine sounds like it is racing before shutdown.

Safety First: Do not run the generator with a suspected overspeed condition; severe damage can occur. Turn the controller to OFF and open the generator breaker.

• 1. Inspect throttle and governor linkage: With engine off, manually move the throttle plate and governor arm. Ensure they move smoothly and return via spring tension. Clean any rust or debris and lightly lubricate pivot points.
• 2. Check governor spring: Verify the governor spring is intact, properly hooked, and not stretched or broken. Replace if damaged.
• 3. Inspect engine speed sensor: Locate the magnetic pickup or flywheel speed sensor on the GE engine. Check that the connector is tight and the sensor tip is clean. Ensure the air gap to the flywheel teeth is set to manufacturer spec (often around 0.020–0.040 in).
• 4. Examine wiring to controller: Trace the speed sensor wiring back to the GE control board. Look for chafed insulation, loose pins, or corrosion at the plug.
• 5. Clear alarm and test: After correcting mechanical issues, clear the Overspeed alarm by cycling the controller OFF then AUTO. Perform a manual test. If overspeed persists, the control board or governor system should be evaluated by a technician.