Cummins/Onan — Replacing the Coolant Pump Belt
Maintenance · Engine cooling system
From a Cummins/Onan service manual — check it applies to your exact model before use.
Applies to: Cummins/Onan HDKA, Cummins/Onan HDKAJ, Cummins/Onan HDKAK
Before you start
- Using the wrong coolant pump drive belt can lead to engine overheating.
Procedure
- Disconnect negative (-) battery cable to prevent accidental starting.
- Remove the 4 bolts securing the pump pulley to its hub.
- Pull the pulley and belt off.
- Run new belt over both pulleys; pull pump pulley up to hub and push on.
- Secure pulley with the 4 bolts and tighten according to Thread Torques.
- Re-attach negative (-) battery cable.
Specs & values
- No means to adjust belt tension; correct replacement belt must be used
- Belt tension increases slightly as engine runs
Full service-parts list: Cummins/Onan HDKA →, Cummins/Onan HDKAJ →, Cummins/Onan HDKAK →
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.