Yanmar 129573-42540 Wear Plate for 4JH3
The Yanmar 129573-42540 is the factory wear plate used in 4JH3 Series engines. It gives the impeller a hard, flat sealing face on one side of the pumping chamber, and it is deliberately the cheapest part in that stack.
In salt water the plate also corrodes and pits, which does the same thing as scoring. A plate that is no longer flat cannot seal against the vanes anywhere across its face, and no amount of care with the rest of the rebuild will make up for it.
Key Features
- Genuine Yanmar replacement wear plate
- Fits 4JH3 Series engines
- One per pump
- Restores the flat sealing face the impeller runs against
- Recovers flow lost to a scored or pitted plate
- Sacrificial part that protects the pump body
Applications
- 4JH3 Series engines
- Raw water pump rebuilds and impeller changes
- Restoring flow after a new impeller did not fix the problem
- Service on a pump that has passed sand or grit
- Repairing corrosion damage inside the pump body
- Spring commissioning and layup service
Specifications
- Brand: Yanmar
- Manufacturer: Yanmar Marine
- Manufacturer Part Number: 129573-42540
- Part Type: Wear Plate
- Fits: 4JH3 Series engines
- Quantity Used: One per pump
- Condition: New
Frequently Asked Questions
Q: Why does the plate wear at all?
Everything the strainer lets through goes between the impeller vanes and the plate. Sand and grit are abrasive, and over a season they polish a set of grooves into the face.
Q: Does it matter which way round it goes?
Yes. One face is the running face and it carries the wear pattern. Note the orientation before removing it, and fit a new plate the same way round.
Q: Can I turn the old plate over and reuse it?
It is not designed to be reversible, and the back face is not finished to run against an impeller. Fit a new one.
Q: Is it worth replacing with every impeller?
Inspect with every impeller and replace when it is marked. On a boat that picks up sand or shell, that often works out to every second impeller.
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 wear plate.
CLRMarine
