Cummins/Onan — Coolant Filter - Replace
Maintenance
From a Cummins/Onan owner's manual covering: QSM11, QSM11 Industrial, QSM11 Marine, QSM1i. Check it applies to your exact model before use.
Applies to: Cummins/Onan QSM1i, Cummins/Onan QSM11 engine
Before you start
- Do not remove pressure cap from a hot engine; coolant can leak when servicing filter.
Parts for this job
Part numbers from the service-parts list for Cummins/Onan QSM1i. Verify against your serial number before ordering; some links are affiliate links.
Procedure
- Remove cooling system pressure cap.
- Turn coolant filter head valve to OFF position.
- Remove and discard coolant filter.
- Clean coolant filter head gasket surface.
- Apply thin film of clean engine oil to new gasket.
- Install new filter until gasket contacts head, tighten 3/4 to 1 turn.
- Turn valve to ON position and install pressure cap.
- Operate engine, check for leaks and coolant level.
Tools required
- 3398145 Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Full service-parts list: Cummins/Onan QSM1i →
Source: Cummins/Onan owner'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.