Water Pump 128397-42500 128990-42500 for Yanmar 2GM20 2YM15 3GM30 3YM20 3YM30

Water Pump for Yanmar

This water pump is a direct replacement cooling water pump for Yanmar marine diesel engines, referencing OEM cross numbers 128397-42500 and 128990-42500.

Overview

The water pump for Yanmar 2GM20, 2YM15, 3GM30, 3YM20, and 3YM30 engines circulates coolant to keep the engine at operating temperature. This water pump is built to match the original mounting and flow requirements of these engines. Replacing a worn water pump for Yanmar helps prevent overheating and cooling system failure.

Built For Performance

• Direct replacement water pump for Yanmar 2GM20, 2YM15, 3GM30, 3YM20, and 3YM30 engines.
• Cross-references OEM part numbers 128397-42500 and 128990-42500.
• Engineered to match original mounting layout for a straightforward installation.
• Designed for marine cooling system duty and continuous operation.
• Provides consistent coolant flow to help maintain engine temperature.
• Constructed as a complete pump assembly for direct installation.

Fits These Machines

• for Yanmar 2GM20
• for Yanmar 2YM15
• for Yanmar 3GM30
• for Yanmar 3YM20
• for Yanmar 3YM30

On-The-Job Use

• Marine diesel engine cooling in auxiliary sailboat and powerboat installations.
• Freshwater and raw water cooling systems for Yanmar inboard engines.
• Replacement during scheduled engine maintenance to prevent overheating failures.
• Repair of aging cooling pumps for Yanmar 2GM and 3GM series engines.

Specs At A Glance

Good To Know

Q: How do I confirm this water pump fits my engine? A: Verify the engine model and serial number against the listed compatible models and OEM cross-reference numbers. These references help ensure the water pump matches the original cooling system layout.

Q: What maintenance should I expect with a marine water pump? A: A marine water pump should be inspected for leaking seals and worn impellers during regular engine service. Replacing the pump before failure helps avoid overheating damage in saltwater or freshwater operation.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.