Sierra 18-3311 Water Pump Kit with Housing for Yamaha Outboards, Replaces 6G5-W0078-A1-00

The Sierra 18-3311 Water Pump Kit with Housing is a complete water pump rebuild kit for Yamaha 2-stroke outboard engines, designed to restore proper cooling system operation when the original pump housing, gasket, or impeller has worn out or failed. Unlike a basic impeller-only repair, this kit includes the pump housing itself along with the gasket and mounting bolts needed to complete the job in one purchase, so you are not left sourcing individual components separately.

Inside the kit, the water pump gasket (part 18-0244, O.E. 6E5-44315-A0-00) seals the housing to the lower unit, four mounting bolts (part 18-0256, O.E. 97095-08045-00) secure the housing in place, and the impeller (part 18-3071) drives coolant through the system. Because the kit includes the housing, it is the correct choice when the housing is cracked, worn, or grooved from a failed impeller, rather than just replacing the wearable parts.

This kit directly replaces the Yamaha OEM water pump kit 6G5-W0078-A1-00 and is built to meet or exceed the performance of the original equipment part. It is intended for Yamaha outboard applications covered by the Yamaha 2-stroke water pump and impeller category, and every Sierra part is backed by Sierra's standard customer satisfaction warranty.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3311
• Product Type: Water Pump Kit
• Includes Housing: Yes
• Kit Contents: Water Pump Housing, Gasket (18-0244), Bolts x4 (18-0256), Impeller (18-3071)
• OEM Cross Reference: 6G5-W0078-A1-00
• Weight: 1.55 pounds
• UPC: 030999755834

Fitment

• Yamaha outboard engines (2-stroke water pump and impeller applications)

Replaces (OEM)

• 6G5-W0078-A1-00

Frequently Asked Questions

What does the Sierra 18-3311 water pump kit include? The kit includes a water pump housing, the water pump gasket (part 18-0244, OEM 6E5-44315-A0-00), four mounting bolts (part 18-0256, OEM 97095-08045-00), and an impeller (part 18-3071).

Does the 18-3311 kit include the water pump housing? Yes, the Sierra 18-3311 is the version of this kit that includes the housing, which is what distinguishes it from a housing-less kit covering the same application.

What OEM part number does the Sierra 18-3311 replace? It replaces Yamaha OEM water pump kit number 6G5-W0078-A1-00.

Is the Sierra 18-3311 a genuine Yamaha part or aftermarket? The 18-3311 is a Sierra aftermarket kit engineered to meet or exceed the performance of the original Yamaha equipment it replaces, not a genuine Yamaha part.

How much does the 18-3311 water pump kit weigh? The Sierra 18-3311 water pump kit weighs 1.55 pounds.

What engines is the 18-3311 water pump kit designed for? This kit is designed for Yamaha 2-stroke outboard engines that use the water pump housing and impeller assembly it replaces.

How many mounting bolts come with the kit, and what size are they? Four mounting bolts are included with the 18-3311 kit, corresponding to OEM part number 97095-08045-00.

What is the difference between the water pump gasket and the impeller in this kit? The gasket (part 18-0244) seals the pump housing against the lower unit to prevent leaks, while the impeller (part 18-3071) is the rotating component that actually pumps cooling water through the engine.

When should I replace the water pump housing instead of just the impeller? If the housing is worn, cracked, or grooved from a failed impeller, replacing just the impeller will not restore proper sealing, so a kit like the Sierra 18-3311 that includes the housing is needed.

Is a UPC available for the Sierra 18-3311 kit? Yes, the Sierra 18-3311 water pump kit carries UPC 030999755834.