Onan 131-0217 Water Pump Wearplate
The Onan 131-0217 Water Pump Wearplate provides the flat running face the impeller seals against on the cover side of the Onan pump housing. Every vane wipes across it thousands of times a minute, so the finish and flatness of this one part have a direct effect on how quickly the pump picks up water on a cold start.
A worn wearplate is a quiet fault. The set still cools at speed but the pump takes longer to prime, flow drops off at low RPM, and the impeller starts wearing unevenly because it is no longer running on a flat face. Fitting a new plate at the same time as the impeller is the cheap way to get the full pump output back. This part is listed for Onan water pump 131-0257 (casting 170-3172) on MCCK 4.0 and 6.5 kW and MDJE 7.5 kW generator sets.
Key Features
- Flat hardened running face for the impeller vane tips
- Dimensioned to the Onan pump housing bore and cover fastener pattern
- Sacrificial wear surface that protects the pump housing and cover
- Restores volumetric efficiency and dry priming after impeller wear
- Fits without machining or shimming of the pump body
Applications
- Raw water pump rebuilds on Onan marine generator sets
- Service after a dry running or overheat event that scored the plate
- Restoring slow priming and low flow at idle
- Full wet end overhaul alongside impeller, cam, seal and gasket
Specifications
- Brand: Onan
- Manufacturer Part Number: 131-0217
- Part Type: Wearplate
- Fits: Onan water pump 131-0257 (casting 170-3172) on MCCK 4.0 and 6.5 kW and MDJE 7.5 kW generator sets
- Quantity Per Pump: 1
- Condition: New
- Shipping Weight: 0.1 lb
Frequently Asked Questions
Q: Does it need sealant on assembly?
No. The plate is clamped between the housing and the cover, and the cover gasket does the sealing.
Q: How do I know the wearplate needs replacing?
Lay it on a known flat surface and check for rock, then run a fingernail across the vane track. A detectable ridge or any through pitting means replace it.
Q: Can a wearplate be sanded flat and reused?
Removing material changes the running clearance and takes off the hardened surface, so a resurfaced plate does not hold up. Fit a new one.
Q: Does the plate go in a particular way round?
Yes. The finished face goes toward the impeller. Fitting it reversed puts the rougher side against the vane tips.
Not sure this is the right part? Send us a Picture of the Pump Plate on your pump and the CLR Marine team will confirm the correct wearplate.