Cummins/Onan — Priming the High-Pressure Side
Repair & overhaul · fuel injection system
From a Cummins/Onan operator's manual — check it applies to your exact model before use.
Applies to: Cummins/Onan HDKA
Before you start
- This procedure should only be performed by a diesel mechanic.
- High pressure oil spray from an injector line fitting can penetrate the skin, leading to possible blood poisoning. Wear safety glasses and keep hands away from the spray.
Procedure
- Loosen the high pressure fittings at the nozzles using two wrenches and flare-nut wrenches.
- Crank the genset until fuel appears at the loosened fittings, then snug up each fitting.
- Shut down the engine and torque the fittings to 19 - 25 lb-ft (25 - 34 N-m).
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Torque fittings to 19 - 25 lb-ft (25 - 34 N-m)
Full service-parts list: Cummins/Onan HDKA →
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.