Cummins/Onan — Water Pump - Remove and Install
Repair & overhaul
From a Cummins/Onan owner's manual covering: M11, M1i Series Engines, ps200da. Check it applies to your exact model before use.
Applies to: Cummins/Onan M11 engine
Before you start
- Do not remove the radiator cap from a hot engine.
Procedure
- Remove the radiator cap after the engine is cool and drain the cooling system.
- Remove the alternator drive belt.
- Remove the water pump pulley retaining capscrew.
- Use pulley puller, Part No. ST-647, and two 5/16 X 18 X 2 capscrews to remove the pulley.
- Remove the alternator and the dust seal.
- Remove the five water pump oil seal capscrews, clamping ring, oil seal and gasket. Discard the oil seal and dust seal.
- Remove the upper radiator hose and loosen the coolant bypass hose clamps.
- Remove the thermostat housing and the water transfer connection capscrews.
- Remove the water pump.
- Install a new o-ring on the water pump mounting flange and install the water pump.
- Install new o-rings and gaskets on the transfer tube and connections.
- Install the oil seal, dust seal, pulley and capscrew.
- Install the alternator and adjust the alternator drive belt.
- Fill the cooling system; operate the engine until it reaches 80 C [180 F] and check for leaks.
Tools required
- Pulley puller, Part No. ST-647 Amazon
- Pulley Pusher Adapter, Part No. 3377401 Amazon
- Pulley Pusher, Part No. 3376326 Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Water pump mounting capscrew torque: 47 Nm [35 ft-lb]
- Water transfer connection capscrew torque: 25 Nm [18 ft-lb]
- Pulley capscrew torque: 75 Nm [55 ft-lb]
- Oil seal capscrews: Step 1 - 7 Nm [60 in-lb]; Step 2 - 20 Nm [180 in-lb]
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.