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FLASHSALE26

Water Pump Repair Kit – Fits Yamaha 25-30HP Outboards (Replaces Yamaha 61N-W0078-11-00, Sierra 18-3432)

Regular price $47.99

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Delivery and Shipping

Orders are typically processed within 1–2 business days.


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


International delivery times may vary due to customs processing.


Tracking information will be provided once your order ships.

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 comprehensive Yamaha Water Pump Repair Kit includes the housing and all necessary components for a complete lower unit service. It is designed to fit Yamaha 4-Stroke F25, F25A, and F25B outboards (25HP, 1998–2017) and 2-Stroke C30 models (30HP, 1993–1997).

The kit serves as a direct interchange for Yamaha part numbers 61N-W0078-00-00 through 61N-W0078-14-00, and Sierra 18-3432, ensuring broad compatibility for the specified engines.

  • Installs in the lower unit to restore cooling system performance.
  • Includes a new housing for a complete and reliable repair.
  • Engineered with a marine-grade corrosion-resistant metal alloy housing.

Part Number Matrix

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

Brand Part Number
Yamaha 61N-W0078-14-00
Yamaha 61N-W0078-13-00
Yamaha 61N-W0078-11-00
Yamaha 61N-W0078-10-00
Yamaha 61N-W0078-01-00
Yamaha 61N-W0078-00-00
Sierra 18-3432

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Yamaha F25 25 4-Stroke 1998–2017 61N-W0078-11-00 Includes F25A and F25B variants
Yamaha C30 30 2-Stroke 1993–1997 61N-W0078-11-00

Technical Specs

Product Type
Outboard Water Pump Repair Kit with Housing
Installation
Lower Unit
Housing Material
Marine-grade corrosion-resistant metal alloy
Housing Color
Silver/Metallic
Weight
238g (8.4 oz)
Fitting Type
Direct fit to specified engines
Other Technical Attributes
Includes housing for complete water pump service

What’s in the Box

  • 1 x Water Pump Impeller (6H4-44352-00)
  • 1 x Key, Woodruff (90280-03M03-00)
  • 1 x Housing, Water Pump (61N-44311-01-00)
  • 1 x Cartridge Outer Plate (61N-44323-00-00)
  • 1 x Insert Cup (61N-44322-01-00)
  • 1 x O-Ring (9310-45161-00)
  • 1 x Water Seal (6L2-44367-00-00)
  • 4 x Bolt (97095-06040-00)

Installation Notes

  1. Disconnect the battery and remove the propeller for safety.
  2. Drain the lower unit gear oil.
  3. Unbolt and carefully remove the lower unit from the outboard's midsection.
  4. Locate the water pump housing on the top of the lower unit and remove its mounting bolts.
  5. Remove the old housing, impeller, cup, plate, and seals. Clean the mounting surfaces thoroughly.
  6. Install the new components from the kit in the reverse order of removal. Ensure the impeller key is correctly seated.
  7. Lightly grease the new impeller and inside the pump cup for easier initial startup.
  8. Reinstall the water pump housing, torquing the bolts to the manufacturer's specification.
  9. Reattach the lower unit to the midsection and refill with fresh gear oil.
  10. Reconnect the battery and test the engine in a suitable water supply to confirm proper water flow.

Troubleshooting & FAQ

How can I confirm this kit fits my exact engine model?

The surest way is to check your engine's model name and year. This kit is specifically for Yamaha 4-Stroke F25/F25A/F25B (1998–2017) and 2-Stroke C30 (1993–1997). You can also cross-reference your existing part number with those listed in the Part Number Matrix.

What are the signs of a failing water pump?

Common symptoms include a weak or intermittent water stream from the "tell-tale" outlet, engine overheating alarms, and reduced engine performance. A worn impeller is the most frequent cause.

How often should the water pump impeller be replaced?

As a general maintenance rule, it's recommended to inspect and/or replace the impeller every 1-2 years or every 100-200 hours of use, depending on operating conditions (e.g., saltwater vs. freshwater).

Why is replacing the full kit, including the housing, important?

The housing and insert cup can wear over time from abrasion, creating a less effective seal. Replacing the entire assembly ensures the new impeller operates at peak efficiency and provides optimal water pressure, extending the life of the repair.

Is any grease or sealant required for installation?

Yes, it is highly recommended to apply a light coat of marine grease to the new impeller and the inside of the pump cup. This lubricates the impeller on its first dry start and helps it seal correctly. No other sealant is typically needed for the main housing.

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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