Cummins/Onan — Setting Magneto Air Gaps
Adjustments · ignition coils (magnetos)
From a Cummins/Onan service manual covering: 5.5 HGJAA, 5.5 HGJAB, 5.5 HGJAC, 5.5 HGJAD, 5.5 HGJAE, 5.5 HGJAF, 7.0 HGJAA, 7.0 HGJAB, 7.0 HGJAC, 7.0 HGJAD, 7.0 HGJAE, 7.0 HGJAF. Check it applies to your exact model before use.
Applies to: Cummins/Onan 5.5 HGJAD, Cummins/Onan 5.5 HGJAE, Cummins/Onan 7.0 HGJAD, Cummins/Onan 7.0 HGJAE
Procedure
- Bar the engine until the flywheel lands directly face the coils.
- Place a 0.012 inch (0.3 mm) feeler gauge between coil and land.
- Hold coil tight against gauge and land.
- Torque the two mounting bolts to 5 lb-ft (7 N-m).
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Magneto air gap 0.012 inch (0.3 mm)
- Mounting bolts 5 lb-ft (7 N-m)
Full service-parts list: Cummins/Onan 5.5 HGJAD →, Cummins/Onan 5.5 HGJAE →, Cummins/Onan 7.0 HGJAD →, Cummins/Onan 7.0 HGJAE →
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.