Yanmar 128990-42511 Sea Water Pump Assembly for 2GM to 3YM30
The Yanmar 128990-42511 is the factory sea water pump assembly for 2GM and 3GM Series engines and 2YM15, 3YM20 and 3YM30 engines. It is driven directly by the engine, so it turns whenever the engine turns, and everything downstream of it in the cooling circuit depends on it holding its output.
There comes a point where rebuilding stops making sense. A pump body that has corroded and pitted around the impeller bore will not seal against a new impeller anywhere; a shaft that is scored where the seal runs will cut a new seal in hours; and a bearing that has taken salt water is on borrowed time whatever else is done. When two or three of those are true at once, a complete pump is the honest answer and it goes back on the engine in an afternoon.
Key Features
- Genuine Yanmar replacement sea water pump assembly
- Fits 2GM and 3GM Series engines and 2YM15, 3YM20 and 3YM30 engines
- Engine driven, no separate power supply needed
- Restores full raw water flow to the cooling circuit
- One per pump
- Direct fit replacement using the original mounting
Applications
- 2GM and 3GM Series engines and 2YM15, 3YM20 and 3YM30 engines
- Replacing a pump with a corroded or pitted body
- Repairing a pump whose bearing has taken salt water
- Restoring cooling after repeated overheat alarms
- Repower and engine refit work
- Keeping a complete spare aboard for long passages
Specifications
- Brand: Yanmar
- Manufacturer: Yanmar Marine
- Manufacturer Part Number: 128990-42511
- Part Type: Sea Water Pump Assembly
- Fits: 2GM and 3GM Series engines and 2YM15, 3YM20 and 3YM30 engines
- Quantity Used: One per pump
- Condition: New
Frequently Asked Questions
Q: What are the warning signs before it fails?
A weak exhaust stream, salt crusting or a weep at the pump drain, a rumble or growl that changes with engine speed, and temperatures that creep up under load.
Q: Should I replace the gasket when fitting it?
Always. The mounting joint has been disturbed, the old gasket has taken a set, and a leak there is both a coolant loss and a corrosion problem.
Q: Is a spare pump worth carrying?
On a boat that goes offshore, yes. A pump can be changed at sea in reasonable conditions, while a body that has failed cannot be repaired with what is aboard.
Q: What should I check after fitting?
Run the engine at the dock and watch the exhaust stream, then check the joint faces for weeping once everything is up to temperature and has cooled again.
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 sea water pump assembly.
CLRMarine
