Cummins/Onan 10W30 — Filling the Cooling System
Maintenance
For the Cummins/Onan 10W30, from the Cummins/Onan operator's manual.
Applies to: Cummins/Onan GGHE, Cummins/Onan GGHF, Cummins/Onan WSG-1068 engine
Before you start
- Do not add cold coolant to a hot engine. Engine castings can be damaged. Allow the engine to cool to below 120 F (50 C) before adding coolant.
- To prevent severe scalding, let engine cool down before removing coolant pressure cap.
Procedure
- Check that all drain cocks are closed and all hose clamps secure.
- Remove the engine coolant vent cap.
- Remove the radiator pressure cap and slowly fill the cooling system with the recommended coolant.
- When coolant begins to flow from the engine coolant vent, install vent cap and continue filling the radiator.
- When the engine is first started, remove the pressure cap and monitor the coolant level; add coolant as trapped air is expelled.
- Replace the pressure cap when the coolant level is stable.
Specs & values
- Cooling system capacity with standard radiator 8.5 Gal (32.2 L)
Full service-parts list: Cummins/Onan GGHE →, Cummins/Onan GGHF →
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.