Yanmar 128170-42110 Seal for 1GM and 1GM10
The Yanmar 128170-42110 is the factory seal used in 1GM and 1GM10 engines. It is a dynamic seal - the shaft slides through it continuously while the engine runs - which is why it wears out on a schedule while the static seals around it last for years.
This is the seal that decides whether the pump survives. Once the lip hardens or the shaft wears a groove under it, salt water finds its way along the shaft to the bearing, and a bearing that has taken salt water fails soon afterwards. The warning is a weep or a salt crust at the pump drain, usually visible long before anything sounds wrong.
Key Features
- Genuine Yanmar replacement seal
- Fits 1GM and 1GM10 engines
- One per pump
- Keeps raw water away from the pump bearing
- Dynamic seal running directly on the pump shaft
- Best replaced as a set with the other pump seals
Applications
- 1GM and 1GM10 engines
- Raw water pump rebuilds
- Curing a weep or salt crust at the pump drain
- Service before salt water reaches the bearing
- Repairing a pump after a bearing failure
- Spring commissioning and layup service
Specifications
- Brand: Yanmar
- Manufacturer: Yanmar Marine
- Manufacturer Part Number: 128170-42110
- Part Type: Seal
- Fits: 1GM and 1GM10 engines
- Quantity Used: One per pump
- Condition: New
Frequently Asked Questions
Q: How do I fit it without damage?
Support it squarely and press on the outer face, never on the lip. Most seals that leak straight after a rebuild were damaged or cocked on the way in.
Q: How often should seals be replaced?
Whenever the pump is apart far enough to reach them, and immediately if there is any sign of water tracking past them.
Q: There is salt crusting under the pump. Is the seal gone?
That is the classic sign. Water is passing the seal and evaporating on the outside. Deal with it early, because the next thing it reaches is the bearing.
Q: Can I fit a new seal to a worn shaft?
Not with much hope. A groove where the old lip ran gives the new one nothing flat to follow, and it will weep again quickly.
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 seal.
CLRMarine
