Cummins/Onan — Adjust injection nozzle opening pressure
Adjustments
From a Cummins/Onan service manual covering: 205D3A, 3DJA, 3DJA-1E2236, 3DJA-3E2236. Check it applies to your exact model before use.
Applies to: Cummins/Onan DJA engine
Before you start
- Do not try to adjust pressure without a testing fixture.
Procedure
- Remove nozzle from engine.
- Remove cap nut over the adjusting screw.
- Install nozzle on static fuel nozzle testing fixture.
- Adjust opening pressure to 1,750 psi by turning adjusting screw.
- Clockwise increases pressure; counterclockwise decreases.
Tools required
- Nozzle tester Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 1,750 psi opening pressure on a used nozzle
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.