Cummins/Onan 50.0 DDB 15R / 50.0 DDB 15R J 1 Q — Priming Fuel System
Maintenance
For the Cummins/Onan 50.0 DDB 15R / 50.0 DDB 15R J 1 Q, from the Cummins/Onan operator's manual.
Applies to: Cummins/Onan 50.0 DDB 15R, John Deere 6329D engine
Before you start
- If the primer lever will not pump and no resistance is felt at upper end of stroke, turn engine over with starter to change position of fuel pump drive lobe on camshaft.
Procedure
- Verify all connections in the fuel system are secure and no leaks exist.
- Loosen bleed plug on top of fuel filter.
- Pump primer lever until a solid stream of fuel, free of air bubbles, flows from bleed plug.
- Secure bleed plug.
- Loosen inlet fuel line on injector pump.
- Operate primer lever on fuel transfer pump until a solid stream of fuel, free of air bubbles, flows from inlet line opening.
- Secure injector pump fuel inlet line.
- Leave fuel transfer pump priming lever at lowest point of stroke.
Full service-parts list: Cummins/Onan 50.0 DDB 15R →, John Deere 6329D engine →
Source: Cummins/Onan operator'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.