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Water Pump Repair Kit – Fits Yamaha 115-150HP 2-Stroke Outboard Engines (Replaces 65N-W0078-A1-00, 65N-W0078-A0-00)

Sale price $39.95 Regular price $63.00
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Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This Water Pump Repair Kit – Fits Yamaha 115-150HP 2-Stroke Outboard Engines is designed for Yamaha 115-150HP 2-Stroke outboard engines, including D150TL and DX150TL models. It provides all the necessary components for a complete and reliable water pump service.

This kit is a direct replacement for Yamaha part numbers 65N-W0078-A1-00 and 65N-W0078-A0-00, and interchanges with Sierra 18-4533.

  • Engineered for direct replacement installation.
  • Contains essential components for a full water pump rebuild.
  • Designed specifically for 2-Stroke engine models.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number Superseded By Notes
Yamaha 65N-W0078-A1-00 Supersedes 65N-W0078-A0-00
Yamaha 65N-W0078-A0-00 65N-W0078-A1-00
Sierra 18-4533 Aftermarket cross-reference

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Yamaha D150TL 150 2-Stroke 65N-W0078-A1-00 Superseded 65N-W0078-A0-00
Yamaha DX150TL 150 2-Stroke 65N-W0078-A1-00 Superseded 65N-W0078-A0-00
Yamaha 115HP 115 2-Stroke 65N-W0078-A1-00 Superseded 65N-W0078-A0-00
Yamaha 150HP 150 2-Stroke 65N-W0078-A1-00 Superseded 65N-W0078-A0-00

Technical Specs

Product Type
Water Pump Repair Kit
Installation
Direct replacement
Housing Material
Rubber, Plastic, Metal
Dimensions
20.0cm L x 11.3cm W x 13.0cm H
Engine Compatibility
For 2-Stroke engines only

What’s in the Box

  • 1 x Insert, Cartridge (61A-44322-02-00)
  • 1 x Gasket, Water Pump (65N-44315-A0-00)
  • 1 x Outer Plate, Cartridge (65N-44323-00-00)
  • 1 x Impeller (6E5-44352-01-00)
  • 4 x Bolt, With Washer (90119-08M14-00)
  • 1 x Key, Woodruff (90280-04M05-00)
  • 1 x O-Ring (93210-37M67-00)
  • 1 x O-Ring (93210-86M38-00)
  • 2 x Pin, Dowel (93606-12019-00)

Installation Notes

  1. Disconnect the battery and shift linkage.
  2. Remove the lower unit mounting bolts and carefully lower the unit.
  3. Unbolt and remove the water pump housing.
  4. Remove the old impeller, plate, and gaskets. Note the orientation of the impeller vanes.
  5. Clean all mating surfaces thoroughly, ensuring they are free of old gasket material and corrosion.
  6. Install the new Woodruff key, gaskets, cartridge insert, and plate.
  7. Slide the new impeller onto the driveshaft while turning it in a clockwise direction to bend the vanes correctly.
  8. Install the new O-rings and re-install the pump housing, torquing bolts to manufacturer specs.
  9. Re-install the lower unit, ensuring the water tube and driveshaft align correctly.
  10. Reconnect the shift linkage and battery, then test the engine with a water supply to verify cooling.

Troubleshooting & FAQ

How do I know if this kit fits my Yamaha outboard?

This kit fits specific Yamaha 115HP and 150HP 2-Stroke models, including the D150TL and DX150TL. Please check the "Engine & Model Compatibility" table and cross-reference your engine's model and OEM part number (65N-W0078-A1-00) to ensure a match.

What are the signs of a failing water pump?

Common signs include the engine overheating, a weak or non-existent "tell-tale" water stream, or a dry, cracked, or brittle impeller found during inspection.

How often should the water pump impeller be replaced?

As a general maintenance guideline, it is recommended to inspect and/or replace the water pump impeller every 1-2 years or every 100-200 hours of operation, depending on usage conditions (e.g., saltwater vs. freshwater).

Is this kit for 2-stroke or 4-stroke engines?

This specific kit is designed exclusively for Yamaha 2-Stroke outboard motors. It is not compatible with 4-stroke models.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost?

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns?

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement, not an OEM component.
  • Professional installation is recommended for safety and performance.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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