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Water Pump Impeller Repair Kit – Fits Yamaha 40/50/60 HP (Replaces 63D-W0078-01-00, 6H3-44352-00-00)

Regular price $29.88

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Orders are typically processed within 1–2 business days.


U.S. orders usually arrive within 6–15 days, depending on stock location and destination.


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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 Impeller Repair Kit – Fits Yamaha 40/50/60 HP Outboards provides a complete solution for servicing Yamaha 40, 50, and 60 HP outboard engines. It is designed for Yamaha 2-Stroke 40/50 HP models (1997–2006) and 4-Stroke F40, F50, and F60 models (1997–Current). The kit restores cooling system performance to prevent engine overheating.

The kit serves as a direct replacement for Yamaha OEM part numbers 63D-W0078-01-00, 63D-W0078-00-00, 63D-W0078-02-00, 63D-W0078-03-00, and Sierra aftermarket part 18-3434.

  • Engineered for direct OEM replacement installation without modifications.
  • Features a durable neoprene impeller and stainless steel components for saltwater and freshwater use.
  • Includes all necessary gaskets, O-rings, and hardware for a complete rebuild.

Part Number Matrix

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

Brand Part Number Notes
Yamaha 63D-W0078-01-00 Primary Replacement Kit
Yamaha 63D-W0078-00-00 Superseded Part
Yamaha 63D-W0078-02-00 Superseded Part
Yamaha 63D-W0078-03-00 Superseded Part
Yamaha 6H3-44352-00-00 Impeller Only
Sierra 18-3434 Aftermarket Interchange

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This kit is compatible with the following Yamaha outboard models:

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Brand Model Rated HP Stroke Years OEM Part No. Notes
Yamaha 40EJRV, 40EJRW, 40EJRX 40 2-Stroke 1997–1999 63D-W0078-01-00
Yamaha 40ELRV, 40ELRW 40 2-Stroke 1997–1998 63D-W0078-01-00
Yamaha 40ESRV, 40ESRW, 40ESRX 40 2-Stroke 1997–1999 63D-W0078-01-00
Yamaha 40MJHV-Z 40 2-Stroke 1997–2001 63D-W0078-01-00
Yamaha 40MLHV-Z 40 2-Stroke 1997–2001 63D-W0078-01-00
Yamaha 40MSHV-X 40 2-Stroke 1997–1999 63D-W0078-01-00
Yamaha 40TLHV 40 2-Stroke 1997 63D-W0078-01-00
Yamaha 40TLR, 40TLRA-D 40 2-Stroke 2002–2005 63D-W0078-01-00
Yamaha 40TLRV-Z 40 2-Stroke 1997–2001 63D-W0078-01-00
Yamaha C40TLRV-Z 40 2-Stroke 1997–2001 63D-W0078-01-00 Commercial model
Yamaha C40TLRA-B 40 2-Stroke 2002–2003 63D-W0078-01-00 Commercial model
Yamaha P40TLHW, P40TLRW 40 2-Stroke 1998 63D-W0078-01-00
Yamaha 50EJRV-Z 50 2-Stroke 1997–2001 63D-W0078-01-00
Yamaha 50ELRV, 50ELRW 50 2-Stroke 1997–1998 63D-W0078-01-00
Yamaha 50TLHV 50 2-Stroke 1997 63D-W0078-01-00
Yamaha 50TLR, 50TLRA-D 50 2-Stroke 2002–2005 63D-W0078-01-00
Yamaha 50TLRV, 50TLRZ 50 2-Stroke 1997, 2001 63D-W0078-01-00
Yamaha C50TLRW-Z 50 2-Stroke 1998–2001 63D-W0078-01-00 Commercial model
Yamaha F40TLRX 40 4-Stroke 1999 63D-W0078-01-00
Yamaha F50LA, F50LB 50 4-Stroke 2012–2016 63D-W0078-01-00
Yamaha F50TLHV 50 4-Stroke 1997 63D-W0078-01-00
Yamaha F50TLR 50 4-Stroke 2005–2011 63D-W0078-01-00
Yamaha F50TLRA-D 50 4-Stroke 2002–2005 63D-W0078-01-00
Yamaha F50TLRV-Z 50 4-Stroke 1997–2001 63D-W0078-01-00
Yamaha F60JA, F60JB 60 4-Stroke 2012–2016 63D-W0078-01-00
Yamaha F60LA, F60LB 60 4-Stroke 2012–2016 63D-W0078-01-00
Yamaha F60LHA, F60LHB 60 4-Stroke 2011–2016 63D-W0078-01-00
Yamaha F60TJR 60 4-Stroke 2005–2007 63D-W0078-01-00
Yamaha F60TJRB-D 60 4-Stroke 2003–2005 63D-W0078-01-00
Yamaha F60TLR 60 4-Stroke 2005–2011 63D-W0078-01-00
Yamaha F60TLRA-D 60 4-Stroke 2002–2005 63D-W0078-01-00
Yamaha T50TLRV 50 4-Stroke 1997 63D-W0078-01-00 High Thrust
Yamaha T50TLRC 50 4-Stroke 2004 63D-W0078-01-00 High Thrust

Technical Specs

Product Type
Water Pump Impeller Repair Kit
Installation
Direct OEM Replacement
Material
Neoprene Impeller, Stainless Steel Cup and Plate
Package Dimensions
15.8 × 10.2 × 5.1 cm (6.22 × 4.02 × 2.01 inches)
Weight
0.24 kg (8.4 oz)
Replaces OEM Part Numbers
63D-W0078-00-00, 63D-W0078-01-00, 63D-W0078-02-00, 63D-W0078-03-00
Replaces Impeller Part Number
6H3-44352-00-00

What’s in the Box

  • 1 x Cartridge Insert (63D-44322-00-00)
  • 1 x Impeller (6H3-44352-00-00)
  • 1 x Pump Housing Cover (63D-44312-00-00)
  • 1 x Cartridge Outer Plate (63D-44323-00-00)
  • 1 x O-Ring (93210-59MG7-00)
  • 1 x Water Pump Gasket (63D-44316-00-00)
  • 4 x Bolts with Washers (90119-08M15-00)
  • 1 x Water Seal Damper 2 (663-44366-00-00)
  • 1 x Woodruff Key (90280-03024-00)

Installation Notes

  1. Disconnect the battery and remove the engine cover.
  2. Drain the lower unit gear lube.
  3. Remove the propeller and the lower unit mounting bolts.
  4. Carefully separate the lower unit from the upper casing.
  5. Unbolt and remove the old water pump housing assembly.
  6. Clean all mating surfaces thoroughly, removing old gasket material.
  7. Install the new woodruff key, impeller, and gaskets from the kit.
  8. Assemble the new pump housing, ensuring the impeller fins are oriented correctly (typically clockwise).
  9. Torque housing bolts to manufacturer specifications.
  10. Re-install the lower unit, ensuring the water tube and driveshaft are aligned correctly.
  11. Refill the gear lube with the recommended oil type.
  12. Reconnect the battery and test the engine in water, verifying water is exiting the tell-tale port.

Troubleshooting & FAQ

How do I know if my water pump is failing?

Common signs include a weak or non-existent water stream from the tell-tale (peephole), engine overheating alarms, or a noticeable drop in cooling performance.

What is the recommended replacement interval for this kit?

For optimal performance and engine safety, it is recommended to inspect the impeller annually and replace the entire water pump kit every 200 hours of use or every two years, whichever comes first. This can vary based on operating conditions (e.g., saltwater vs. freshwater).

Do I need special tools for this installation?

Basic mechanics tools such as a socket set, torque wrench, and gasket scraper are required. A flywheel puller may be needed on some models, though not always necessary for a lower unit service.

My engine model isn't listed, but the HP is correct. Will it fit?

Do not assume fitment based on horsepower alone. To ensure compatibility, you must verify your specific engine model and year against the compatibility chart. Part numbers can vary significantly between models.

What is the purpose of the woodruff key?

The woodruff key locks the impeller to the driveshaft, ensuring it spins with the shaft to pump water. It is a critical component that should always be replaced during a water pump service.

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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