Cummins/Onan — Raw Water Pump Major Service Kit Installation

Maintenance

From a Cummins/Onan service manual — check it applies to your exact model before use.

Applies to: Cummins/Onan MDKAD, Cummins/Onan MDKAE, Cummins/Onan MDKAF

Procedure

1. Remove the four screws holding water pump on engine.
2. Remove impeller as described in Minor Service Kit.
3. Remove housing from cast iron body by removing three hex head bolts from back side.
4. Use pliers to remove key from pump shaft.
5. Pry wear plate off cast iron body with flat tip screwdriver.
6. Press water lip seal out from wear plate; remember directional position.
7. Inspect shaft for excess grooving and wear; grooving exceeding .015 in depth requires complete pump replacement.
8. Remove cam by unscrewing cam screw and seal washer.
9. Begin reassembly by replacing cam, seal washer and cam screw; reassemble all parts in reverse order.
10. Apply Permatex or equivalent gasket-forming sealant to outer diameter of new seal case; press new water lip seal into new wear plate in same direction as old seal.
11. Clean dirt or corrosion from cast iron body and shaft; push wear plate and seal over shaft into body.
12. Replace key with new one from kit; install wear plate before replacing key.
13. Position new O-ring seal gasket and attach pump housing using three longer bolts (#7).
14. Reassemble impeller as described in Minor Service Kit section.

Full service-parts list: Cummins/Onan MDKAD →, Cummins/Onan MDKAE →, Cummins/Onan MDKAF →

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.

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