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Propeller Shaft Oil Seal 2-Pack – Fits Yamaha 115–300 HP (Replaces 93101-30M17-00, Sierra 18-0266, Mallory 9-76422)

Sale price $20.00 Regular price $22.00

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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@seasierra.com, and we’ll get back to you within 20–36 hours.

Product Details

This aftermarket Propeller Shaft Oil Seal 2-Pack is intended for Yamaha outboard lower-unit and gearcase applications within the listed 115–300 HP range. The seals help prevent water intrusion and gear-lubricant leaks around the propeller shaft when correctly matched to the engine and bearing-carrier assembly.

This product is listed as a replacement for Yamaha OEM part number 93101-30M17-00, Sierra 18-0266, and Mallory 9-76422. Confirm the original part number, dimensions, engine model, year, and serial-number range before ordering.

  • Designed for installation in the lower-unit gearcase assembly.
  • Spring-loaded design supports consistent sealing performance.
  • Marine-grade CR rubber construction for freshwater and saltwater service.
  • Sold as a set of two propeller shaft oil seals.

Part Number Matrix

Use the following references to compare the listed OEM and aftermarket numbers. Part-number comparison does not replace exact model and application verification.

Brand Part Number Reference
Yamaha 93101-30M17-00 Listed OEM replacement reference
Sierra 18-0266 Listed aftermarket replacement reference
Mallory 9-76422 Listed aftermarket replacement reference

Engine & Model Compatibility

The available product record identifies this seal for Yamaha outboards in the broad 115–300 HP range. Exact fitment can vary by model, year, stroke, shaft configuration, lower-unit design, and serial number.

Brand Application Range Rated HP Stroke / Year / Serial OEM Reference
Yamaha Outboard lower-unit propeller-shaft applications 115–300 HP Verify the exact engine model, year, stroke, and serial-number range 93101-30M17-00

Important: Do not rely on horsepower alone. Compare the removed seal, OEM reference, dimensions, and engine identification information before installation.

Technical Specs

Product Type
Propeller Shaft Oil Seal
Package Quantity
2 seals
Installation Location
Lower Unit / Gearcase
Dimensions
45.25 mm OD × 28.5 mm ID × 7 mm width
Housing Material
Marine-grade CR rubber
Design
Spring-loaded sealing design
Product Status
Aftermarket replacement; not an OEM Yamaha component

What’s in the Box

  • 2 × Propeller Shaft Oil Seal

Installation Notes

  1. Drain the gearcase lubricant completely from the lower unit.
  2. Remove the propeller, thrust washer, and related hardware.
  3. Unbolt and carefully extract the bearing-carrier housing from the gearcase.
  4. Note the orientation of the old seals before removal.
  5. Use a dedicated seal puller to remove the old seals without scratching the housing.
  6. Thoroughly clean the seal-seating area inside the housing.
  7. Lightly lubricate the outer surface of the new seal and press it into the housing squarely with a correctly sized seal driver or socket.
  8. Install the second seal in the correct orientation for the bearing-carrier design. Do not assume both seals face the same direction.
  9. Reinstall the bearing-carrier housing with new O-rings or gaskets as required, and torque fasteners to the manufacturer’s specifications.
  10. Reinstall the propeller and refill the gearcase with the correct marine gear lubricant before operation.

Troubleshooting & FAQ

How can I tell if my propeller shaft seal is failing?

Common signs include milky, creamy, or cloudy gear lubricant, which indicates water contamination, or visible gear-oil leakage around the propeller-shaft area of the lower unit.

Will this seal fit my specific Yamaha outboard?

The listed application range is Yamaha 115–300 HP, but horsepower alone does not confirm fitment. Verify the exact model, year, stroke, serial-number range, original seal dimensions, and OEM reference 93101-30M17-00 before ordering.

Why are two seals included?

Some Yamaha lower-unit bearing-carrier designs use two propeller-shaft seals installed together. This package includes two seals, but the correct seal orientation and installation arrangement must be confirmed for the specific gearcase.

Is this an OEM Yamaha part?

No. This is an aftermarket replacement seal. Yamaha 93101-30M17-00 is provided as the listed OEM reference for comparison.

What maintenance is recommended after installation?

Inspect the lower unit during routine service and check the gear lubricant for water contamination or leakage. Replace the seals if leakage or water intrusion is found.

How fast is shipping?

Typical transit is 5–15 days for most regions. Standard shipping is free, and expedited options may appear at checkout where available.

What is the warranty and return policy?

This product is covered by a 1-year warranty against manufacturing defects under normal use. Returns are accepted within the standard store return window for unused items in their original condition.

Safety & Important Information

  • Verify the part number, dimensions, engine identification, and seal orientation before installation.
  • Do not treat the broad 115–300 HP range as confirmation of fitment for every Yamaha model.
  • This is an aftermarket replacement part, not an original equipment manufacturer component.
  • Professional installation is strongly recommended for lower-unit service.
  • After installation, pressure-test the gearcase when appropriate and check the lubricant for leaks or water contamination.

About Sea Sierra

  • Pro-Grade Standards — We supply marine replacement parts intended for demanding freshwater and saltwater service.
  • Fast Global Fulfillment — We offer free standard delivery to most regions, with typical transit times of 5–15 days.
  • Manufacturer-Direct Value — We work with manufacturing partners to provide practical replacement parts at competitive prices.

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