Cummins/Onan — Cooling System Filling
Maintenance
From a Cummins/Onan operator's manual — check it applies to your exact model before use.
Applies to: Cummins/Onan MDKUB, Cummins/Onan MDKWB, Kubota Z482B engine, Kubota D722B engine
Before you start
- Contact with hot coolant can cause severe burns.
- Never pour hot water into a cold engine or cold water into a hot engine.
Procedure
- Verify all drain cocks are closed and all hose clamps secure.
- Remove pressure cap and slowly fill cooling system with coolant mixture.
- Fill recovery tank to FULL mark.
- Operate genset until normal operating temperature is maintained (about 15 minutes).
- Shut down, let cool, add coolant to recovery tank until level stabilizes at Full mark.
Specs & values
- 50/50 mixture of ethylene glycol anti-freeze and water
Full service-parts list: Cummins/Onan MDKUB →, Cummins/Onan MDKWB →, Kubota Z482B engine →
Source: Cummins/Onan operator's 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.