Cummins/Onan LS-15M — Angular Alignment Procedure
Adjustments · Generator to engine alignment
For the Cummins/Onan LS-15M, from the Cummins/Onan service manual.
Applies to: Cummins/Onan DFAA, Cummins/Onan DFAB, Cummins/Onan DFAC, Cummins/Onan DFBF, Cummins/Onan DFCB, Cummins/Onan DFCC, Cummins/Onan DFCE, Cummins/Onan DFE
Before you start
- Accidental starting of the generator set during this procedure presents the hazard of severe personal injury or death. Make sure to disconnect the negative (-) battery cable(s) before beginning.
Procedure
- Disconnect the negative (-) battery cable(s) before beginning.
- Fasten a dial indicator to the generator shaft or cooling fan with sensing point on capscrew head or flat surface of drive disc at bolt circle diameter.
- Bar the engine over in a clockwise rotation as viewed from engine flywheel; do not allow it to roll back on compression.
- Record maximum positive and negative dial indicator readings as the engine completes one revolution.
- T.I.R. equals the sum of the maximum positive and negative readings.
- Maximum T.I.R. should not be more than .001 inch for each inch of radius.
- Remove equal shims from under both generator mounting feet to lower the generator.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Maximum allowable T.I.R.: .001 inch per inch of radius (center of shaft to indicator axis)
Full service-parts list: Cummins/Onan DFBF →, Cummins/Onan DFCC →, Cummins/Onan DFCE →, Cummins/Onan DFE →
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.