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FLASHSALE26

18-2785 Lower Unit Seal Kit for Yamaha 25 Hp Outboard 1984-85 | SeaSierra

Sale price $51.99 Regular price $88.00

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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: 182785
  • Manufacturer & Brand: SeaSierra
  • Category: Seal Kits

Compatibility:

Fits the Following Yamaha Applications:

  • 25 Hp 1984-85 WSM 18-2785

Part Numbers and Replacements:

  • Replaces OEM Part Numbers:
    • 689-W0001-21-00
    • 689-W0001-C1-00
  • Equivalent Kits:
    • Sierra 18-2785 Lower Unit Seal Kit
    • Interchangeable with Mercury Marine 27-41899M and 27-84828M
    • Interchangeable with Yamaha Outboard 689-W0001-21-00 and 689-W0001-C1-00

Kit Components:

Seal Kit Contains:

  • Water pump gasket
  • Cartridge gasket
  • Water seal damper
  • O-ring (2x)
  • 18-99010 Exhaust manifold gasket
  • 18-4698 Drain fill washer
  • 18-0296 Oil seal
  • 18-0554 Oil seal

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