Generator runs but frequency is unstable, causing lights to flicker or motors to run erratically.

Safety first: Isolate critical loads until frequency is stable. Avoid operating sensitive electronics on unstable power.

• Observe governor action: Watch the throttle and governor linkage while the engine runs. If it oscillates rapidly, the governor may be hunting.
• Lubricate linkage: Clean and lightly lubricate pivot points to ensure smooth movement.
• Check speed sensor signal: Inspect wiring and connector. Replace the sensor if RPM readings are erratic.
• Adjust governor settings: Using the Siemens service manual, adjust governor gain and stability parameters to reduce hunting. This is best done by a trained technician.