Cummins/Onan 6.3 NHEL / 6.5 NH — Choke Adjustment
Adjustments · Automatic choke
For the Cummins/Onan 6.3 NHEL / 6.5 NH, from the Cummins/Onan service manual.
Applies to: Cummins/Onan NHEL
Before you start
- The choke gets very hot during normal operation and can cause severe burns if touched. Do not remove choke cover while the set is operating.
Procedure
- Stop set and allow it to cool down before making adjustments.
- Remove protective plastic choke cover and loosen heating element cover screws.
- Rotate heating element until choke plate is about halfway open.
- Slowly rotate cover counterclockwise while tapping the carburetor choke lever until it no longer bounces (fully-closed reference position).
- Refer to Table 6-3 for degrees to rotate element cover clockwise from reference position (marks spaced at 5 degrees).
- Rotate element cover as specified and tighten cover mounting screws.
- Move choke lever back and forth to check smooth operation and automatic return.
- Install plastic choke cover and tighten center mounting nut.
Tools required
- Screwdriver Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Choke settings per Table 6-3 vs ambient air temperature (40°F/4°C = reference fully closed)
- Each mark on choke housing equals 5 degrees angular rotation
Full service-parts list: Cummins/Onan NHEL →
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.