Cummins/Onan — Coolant Level - Check
Maintenance · Cooling system / radiator
From a Cummins/Onan operator's manual — check it applies to your exact model before use.
Applies to: Cummins/Onan DQFAA, Cummins/Onan DQFAB, Cummins/Onan DQFAC, Cummins/Onan DQFAD, Cummins/Onan QST30-G5 engine
Before you start
- Do not open the pressure cap while the engine is running; let the engine cool down and relieve pressure first.
- Do not add cold coolant to a hot engine; allow engine to cool to below 50 °C (122 °F).
Procedure
- Isolate the generator set to prevent accidental starting whilst filling the radiator.
- Slowly remove the radiator filler cap.
- Coolant level should be level with the bottom of the filler neck.
- Slowly fill with a 50/50 mixture of fully formulated coolant and DCA4 until level reaches bottom of filler neck.
- Replace the radiator cap securely - push down and twist clockwise until cap lip hits stop flange.
- Start the generator set and check for leaks.
Specs & values
- Coolant level at bottom of filler neck
- 50/50 coolant/DCA4 mixture
Full service-parts list: Cummins/Onan DQFAA →, Cummins/Onan DQFAB →, Cummins/Onan DQFAC →, Cummins/Onan DQFAD →
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.