Cummins/Onan — Engine Speed Adjustments (Low-Idle and High-Idle)
Adjustments · Carburetor and throttle linkage
From a Cummins/Onan operator's manual covering: P216, P218, P220, P224. Check it applies to your exact model before use.
Applies to: Cummins/Onan P216, Cummins/Onan P218, Cummins/Onan P220, Cummins/Onan Performer Series
Before you start
- Adjusting engine speed above that specified by the equipment manufacturer could violate Federal and State Standards for Safety
- Only a qualified mechanic should adjust engine speed
Procedure
- Start the engine, observing all equipment manufacturer instructions and precautions.
- Loosen throttle cable clamp and back out low-idle speed stop screw so carburetor speed stop screw touches its stop.
- Adjust engine speed to 1000 RPM with the carburetor speed stop screw.
- Turn the low-idle speed stop screw to obtain the specified low-idle speed.
- Move the engine throttle link against its stop tang and bend the tang for specified high-idle speed.
- Hook throttle link with the cable, remove slack and tighten the clamp.
- Check for full, smooth movement of the throttle link between its two stop positions.
Tools required
- Accurate tachometer Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Set low-idle and high-idle to values in the equipment Operator's Manual; absent specifications, 1100 RPM low idle and 3400 RPM high idle
Full service-parts list: Cummins/Onan P216 →, Cummins/Onan P218 →, Cummins/Onan P220 →, Cummins/Onan Performer Series →
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.