Cummins/Onan — Axial Alignment Procedure (750 kW gensets and larger)
Adjustments · generator/engine coupling
From a Cummins/Onan service manual — check it applies to your exact model before use.
Applies to: Cummins/Onan DFGB, Cummins/Onan DFGE, Cummins/Onan DFLB, Cummins/Onan DFLC, Cummins/Onan DFLE, Cummins/Onan VTA28-G5 engine, Cummins/Onan KTA50 engine
Procedure
- Check axial alignment only when objectionable vibration is present after angular alignment
- Fasten dial indicator holding device to skid base/engine block/generator shell, sensor on generator shaft hub
- Bar engine over clockwise through a couple of rotations, recording readings at eight equally spaced points
- If out of tolerance, remove capscrews connecting drive discs and flywheel, mark discs, reposition holes 180 degrees
- Reinstall capscrews and retorque; recheck alignment; try 30/60/90 degree repositioning if unchanged
Tools required
- dial indicator Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Recommended to reduce measured T.I.R. runout by one half
Full service-parts list: Cummins/Onan DFGB →, Cummins/Onan DFGE →, Cummins/Onan DFLB →, Cummins/Onan DFLC →, Cummins/Onan DFLE →
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.