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FLASHSALE26

18-2789 Lower Unit Seal Kit Compatible with Yamaha 25 Hp 1997-02 | Sea Sierra

Sale price $39.90 Regular price $48.00

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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: 182789
  • Brand & Manufacturer: Sea Sierra
  • Category: Drive Parts / Seal Kits, Oil Seals
  • Part Type: Lower Unit Seal Kit
  • Packaging Dimensions
    • Weight: 0.225 lbs
    • Height: 0.45 inches
    • Depth: 9.9 inches
    • Width: 12.95 inches

Compatibility

This Lower Unit Seal Kit is compatible with Yamaha 25 Hp engines produced in the years 1997-2002 (WSM 18-2789).

Kit Components

The package includes the following components suitable for Yamaha 25 Hp engines:

  • Gasket, Upper Casing (6J8-W0001-20-00)
  • Gasket, Upper Casing (6J8-W0001-21-00)
  • Gasket, Upper Casing (6J8-W0001-22-00)
  • Gasket, Upper Casing (6J8-W0001-C2-00)
  • O-Ring
  • O-Ring
  • Drain Fill Washer (18-4698)
  • Drain Fill Washer
  • Gasket, Water Pump (18-0292)
  • Gasket, Water Pump
  • Gasket, Water Pump (18-0294)
  • Gasket, Water Pump
  • O-Ring (18-0298)
  • O-Ring
  • Oil Seal (18-0297)
  • Oil Seal
  • Oil Seal (18-0554)
  • Oil Seal
  • Gasket, Water Pump (18-99149)
  • Gasket, Water Pump

Part Numbers and Replacements

  • Replaces OEM Part Numbers:
    • 6J8-W0001-21-00
    • 6jW0001-C2-00

Additional Information

  • High Performace Quality OEM Style Gaskets.
  • Gaskets and seals meet OEM standards or higher.
  • Please be advised that Mercury/Mariner motors DO NOT go by the year they were produced. So please check all information available such as the following to identify your engine to the correct part.
  • If you are looking for performance parts, we offer the best distinguished brands and handpick the parts that we know work and use daily.

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