HomeRepair guidesRemoval:

Compatible — Removal:

For these models: J8-JC Series, JB, JB-E, JB-JC, jB-M, jB-R, jC.

Procedure

  1. Remove the gear cover and oil base (Refer to Engine
  2. Remove the crankshaft lock ring and gear retaining
  3. Loosen the two capscrews holding the pump and remove

Source: manual:967-0500_Onan_JB_JC_Genset_Engine__Magneciter_Gen-end_Service_Manual_11-1971_bestmanual.pdf. Figures and steps are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.