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FLASHSALE26

18-3425 Water Pump Impeller Kit for Yamaha 25, 40, 50 HP C25, P50, Pro50 2-Stroke | SeaSierra

Sale price $19.89 Regular price $35.00

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Shop with confidence. If you’re not completely satisfied, eligible items may be returned within the return window, provided they are unused and in original packaging.


If the return is due to our error or a defective item, we’ll make it right.


Please contact us before returning any item.

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

  • SKU: 183425
  • Brand & Manufacturer: SeaSierraCategory: Outboard Motor Parts
  • Part Type: Water Pump Impeller Repair Kit
  • Item Weight: 0.47
  • Package Dimensions: 4.9 x 4.6 x 2.6 inches

Compatibility

This kit is compatible with the following Yamaha Two Stroke Outboard models:

  • 25 HP (International Model 25Q): 1990-1994
  • 40 HP: 1984-1995 (International: 1984-1995)
  • 50 HP: 1984-1987, Pro Series 50: 1987-1990, P50: 1995-1996 (International: 1984-1994)

Part Numbers and Replacements

  • Replaces OEM Part Numbers:
    • 6H4-W0078-A0-00
    • 6H4-W0078-01-00
    • 6H4-W0078-00-00
  • Replaces Sierra Part Numbers:
    • 18-3429
    • 18-3408
  • GLM Part Number: 12064, 12287
  • SEI Marine Part Numbers: 96-499-01CK, 96-499-02CK
  • Other Replaced Part Numbers: 663-W0078-00-00, 663-W0078-A0-00, Mercury Marine: 84188M, 84188T

Kit Components

The package includes the following items:

  1. Impeller (6H4-44352-02/00, 18-3068) - Suitable for engines with 25, 40, 50 HP
  2. Cartridge Outer Plate (663-44323-00, 18-3436)
  3. Insert Cup (663-44324-00, 18-3435)
  4. Gaskets (663-44315-00, 663-44324-00, 663-44316-00)
  5. Water Seal
  6. Key, Woodruff
  7. 4 x Bolts

Additional Information

  • Other Part Numbers: Bolt (NSS, 18-0256), Gasket, Water Pump (18-0292, 18-0294), Impeller (18-3069), Impeller Key (18-3297), Wear Plate (18-3436), Water Seal Damper (18-1830)

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