Cummins/Onan — Immobilizing for Safe Working
Maintenance · Generator set
From a Cummins/Onan service manual — check it applies to your exact model before use.
Applies to: Cummins/Onan DFEJ, Cummins/Onan DFEK, Cummins/Onan QSX15-G9 engine
Before you start
- The generator set cannot be considered safe to work on until the engine is properly immobilized.
Procedure
- Press the Off mode switch on the operator panel to shut down the generator set.
- Press the Emergency Stop button to prevent the generator set starting, regardless of the Start signal source.
- Thoroughly ventilate the plant room before disconnecting any leads.
- Isolate and lock off the supply to the heater, where fitted.
- Isolate and lock off the supply to the battery charger, where fitted.
- Isolate the fuel supply to the engine.
- Using an insulated wrench, disconnect the negative (-) cable first on the starting batteries and control system batteries.
- Fit warning notices at each of the above points to indicate Maintenance in Progress - Plant Immobilized for Safe Working.
Tools required
- Insulated wrench Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Full service-parts list: Cummins/Onan DFEJ →, Cummins/Onan DFEK →
Source: Cummins/Onan service 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.