Generac — Out of Service Procedure

Maintenance · Generator storage

From a Generac owner's manual — check it applies to your exact model before use.

Applies to: Generac GH-410 engine, Generac GT-530 engine, Generac GT-990 engine, Generac GT-999 engine

Procedure

1. Start the engine and let it warm up.
2. Close the fuel shutoff valve in the fuel supply line and allow the unit to shut down.
3. Switch to the OFF position.
4. Set the generator's main circuit breaker to OFF (or OPEN).
5. Set AUTO/OFF/MANUAL switch to OFF and turn off utility power to the transfer switch.
6. Remove the 7.5A fuse from the generator control panel and disconnect battery cables.
7. Drain the oil completely while the engine is still warm and refill the crankcase with oil.
8. Attach a tag to the engine indicating the viscosity and classification of the oil.
9. Remove the spark plug(s) and spray fogging agent into the spark plug threaded openings, then reinstall and tighten.
10. Remove the battery and store it in a cool, dry room on a wooden board.
11. Clean and wipe the entire generator.

Source: Generac owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.

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