Cummins/Onan — LPG Converter Test
Testing & diagnosis · LPG converter (regulator)
From a Cummins/Onan service manual covering: P216, P218, P220, P248. Check it applies to your exact model before use.
Applies to: Cummins/Onan P216, Cummins/Onan P218, Cummins/Onan P220, Cummins/Onan P248
Before you start
- LPG is flammable and explosive and can cause severe personal injury or death. Keep flames, sparks, and other ignition sources away. Close the manual fuel shutoff valve before disconnecting the LPG fuel line.
Procedure
- Connect a pressure gauge to the test port on the side of the converter.
- Connect a source of compressed air of at least 80 psi (550 kPa) to the inlet opening and open the air pressure valve.
- If the primary valve is sound, the gauge will indicate approximately 1.5 psi (10.3 kPa) and pressure will remain constant.
- Fluctuating pressure indicates a leaking primary valve seat.
- Close the air pressure valve and observe the gauge; if pressure remains constant the secondary valve seat is sound.
- If the pressure drops, the secondary valve seat is leaking. Replace the converter if it does not pass either test.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Primary valve pressure approximately 1.5 psi (10.3 kPa)
Full service-parts list: Cummins/Onan P216 →, Cummins/Onan P218 →, Cummins/Onan P220 →, Cummins/Onan P248 →
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.