Generac GT-990 — Break-in Procedure

Operation · Generator

For the Generac GT-990, from the Generac owner's manual.

Applies to: Generac GT-990 engine

Procedure

1. Set AUTO/OFF/MANUAL switch to AUTO.
2. Turn OFF utility power to the transfer switch.
3. Unit starts and transfer switch transfers to standby.
4. Run one hour at 25% rated load.
5. Run one hour at 50% rated load.
6. Run one hour at 75% rated load.
7. Run one hour at 100% rated load.
8. Turn ON utility power; unit runs one minute then shuts down.
9. Allow unit to cool.
10. Set switch to OFF, remove 7.5A and 15A fuses, disconnect battery cables.
11. Drain oil and replace the oil filter; refill with synthetic oil.
12. Reconnect battery cables and insert fuses into control panel.

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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