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FLASHSALE26

Water Pump Repair Kit for Yamaha 2 HP 2-Stroke Outboards – Replaces 6A1-W0078-02 and 6GD-W0078-00-00

Regular price $26.95

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Product Details

This aftermarket water pump repair kit is designed for selected Yamaha 2 HP 2-stroke outboard motors. It is intended for water pump service using the existing water pump housing and helps restore cooling-water circulation during routine maintenance or repair.

The kit is listed for Yamaha outboards using OEM reference numbers 6A1-W0078-02 and 6GD-W0078-00-00. Listed aftermarket cross-references include 18-3462 and 18-3463. These numbers are provided for identification and cross-reference; confirm the exact part number, model and year before ordering.

  • For selected Yamaha 2 HP 2-stroke outboard applications.
  • Water pump service kit for replacement of worn pump-service parts.
  • Designed for installation with the existing water pump housing.
  • Aftermarket replacement; not manufactured by Yamaha.

Part Number Matrix

Use the following references to compare the required water pump repair kit with your existing part and service documentation.

Brand or Source Part Number Reference
Yamaha 6A1-W0078-02 Company-listed OEM reference
Yamaha 6GD-W0078-00-00 Company-listed OEM reference
Aftermarket 18-3462 Company-listed aftermarket reference
Aftermarket 18-3463 Company-listed aftermarket reference

Engine & Model Compatibility

Fitment depends on the exact Yamaha model, year and part-number configuration. The catalog relationships below identify selected 2 HP 2-stroke applications associated with the Yamaha water pump repair kit reference 6A1-W0078-02-00.

Brand Model Rated HP Stroke Year OEM Part No. Notes
Yamaha 2SF 2 HP 2-Stroke 1989 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHP 2 HP 2-Stroke 1990–1991 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2SD 2 HP 2-Stroke 1990–1991 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHQ 2 HP 2-Stroke 1992 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHR 2 HP 2-Stroke 1993 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHS 2 HP 2-Stroke 1994 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHT 2 HP 2-Stroke 1995 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHU 2 HP 2-Stroke 1996 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHV 2 HP 2-Stroke 1997 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHW 2 HP 2-Stroke 1998 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHX 2 HP 2-Stroke 1999 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHY 2 HP 2-Stroke 2000 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHKZ 2 HP 2-Stroke 2001 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHZ 2 HP 2-Stroke 2001 6A1-W0078-02-00 Water pump repair kit application
Yamaha 2MSHA 2 HP 2-Stroke 2002 6A1-W0078-02-00 Water pump repair kit application

Important: The applications above are model-and-year-specific catalog references, not a universal fitment claim for every Yamaha 2 HP outboard. Check the model designation, year and existing water pump part number before installation.

Technical Specs

Product Type
Water pump repair kit
Application
Selected Yamaha 2 HP 2-stroke outboards
Installation
Service replacement using the existing water pump housing
Housing Included
No; water pump housing is not included
OEM References
6A1-W0078-02; 6GD-W0078-00-00
Aftermarket References
18-3462; 18-3463
Product Status
Aftermarket replacement, not an OEM Yamaha component

What's in the Box

  • 1 x Yamaha-compatible water pump repair kit
  • Water pump housing not included

Individual component quantities and part-level markings may vary by production batch. Compare the supplied parts with the original service parts before disassembly.

Installation Notes

  1. Confirm the engine model, year and required water pump reference before beginning work.
  2. Stop the engine, disconnect the battery where applicable, shift to neutral and follow the manufacturer's service-safety procedures.
  3. Remove the lower unit from the outboard according to the applicable service manual.
  4. Remove the water pump housing and inspect the housing, drive key, shaft and mating surfaces.
  5. Remove the worn water pump service parts and clean all sealing and contact surfaces.
  6. Install the replacement kit components according to the engine service manual and the original component arrangement.
  7. Make sure the impeller drive key is correctly seated and the impeller vanes are oriented as specified by the manufacturer.
  8. Reinstall the existing water pump housing and tighten fasteners to the manufacturer's torque specifications.
  9. Reattach the lower unit and complete the shift-linkage and control checks required by the service manual.
  10. Run the engine only in the water or with an approved flushing device, then verify a steady tell-tale stream and check for leaks or overheating.

Troubleshooting & FAQ

How do I confirm that this kit fits my motor?

Match your Yamaha outboard's model, year and existing water pump part number with the compatibility information above. The primary listed application is selected 2 HP 2-stroke Yamaha outboards using 6A1-W0078-02 or the listed 6GD-W0078-00-00 reference.

Is this kit for Mercury or Mariner 4-stroke outboards?

No. The company record for this product identifies it as a Yamaha Outboard water pump service kit for 2 HP 2-stroke applications. Mercury and Mariner 4-stroke compatibility is not part of this listing.

Is the water pump housing included?

No. This is a water pump repair kit intended for use with the existing water pump housing. Inspect the housing for scoring, corrosion or excessive wear and replace it separately if necessary.

What symptoms indicate a worn water pump?

Common symptoms include a weak or intermittent tell-tale stream, overheating, reduced cooling performance or visible damage to the impeller and related pump parts. Stop operation and inspect the cooling system if overheating occurs.

How often should the water pump be serviced?

Follow the maintenance interval in the engine manufacturer's service manual. Inspection may be needed more frequently when operating in sandy, silty or debris-filled water.

Is this an OEM Yamaha part?

No. This is an aftermarket replacement kit listed for the Yamaha OEM references shown on this page.

Safety & Important Information

  • Verify the exact Yamaha model, year and part number before purchase and installation.
  • Do not operate an outboard with an unknown or inadequate cooling-water stream.
  • Use the applicable factory service manual for torque values, lower-unit removal and final testing.
  • Professional installation is recommended when lower-unit or water-pump service procedures are unfamiliar.

About Sea Sierra

  • Marine replacement parts selected for practical service and maintenance applications.
  • Clear part-number references to help customers compare replacement components.
  • Support for product-identification questions before ordering.

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