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FLASHSALE26
34% off

Water Pump Oil Seal – Fits Yamaha 115-300HP (Replaces 93101-28M16-00)

Sale price $7.89 Regular price $12.00

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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 replacement Water Pump Oil Seal is designed for a broad range of Yamaha 2-stroke and 4-stroke outboard engines from 115HP to 300HP, covering models from 1984 to the present. It serves as a crucial component for maintaining the integrity of the water pump assembly, preventing leaks and ensuring efficient operation.

This part directly replaces Yamaha OEM part 93101-28M16-00 and is interchangeable with Sierra 18-0265, Mallory 9-76412, and Mallory 9-76421.

  • Engineered for a stacked installation where two seals are used together.
  • Designed specifically as an S-Type oil seal for marine water pump applications.
  • The package includes two seals, providing a complete set for one engine service.

Part Number Matrix

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

Brand Part Number Notes
Yamaha 93101-28M16-00 Current OEM
Yamaha 93101-28018 Superseded by 93101-28M16-00
Yamaha 93101-028019 Superseded by 93101-28M16-00
Sierra 18-0265 Aftermarket Interchange
Mallory 9-76412 Aftermarket Interchange
Mallory 9-76421 Aftermarket Interchange

Engine & Model Compatibility

Confirm your engine model and year in the table below.

This seal fits a wide variety of V4 and V6 Yamaha outboards, including models in the high-performance SHO/VMAX series.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Yamaha Various V4/V6 115-130 2-Stroke 1984+ 93101-28M16-00
Yamaha Various V4/V6 150-175 2-Stroke 1984+ 93101-28M16-00
Yamaha Various V4/V6 200-225 2-Stroke 1984+ 93101-28M16-00
Yamaha Various V4/V6 250-300 2-Stroke 1984+ 93101-28M16-00
Yamaha F115 115 4-Stroke 2000+ 93101-28M16-00
Yamaha F150-F200 150-200 4-Stroke 2000+ 93101-28M16-00
Yamaha F225-F300 225-300 4-Stroke 2000+ 93101-28M16-00
Yamaha VF115-VF250 115-250 4-Stroke 2000+ 93101-28M16-00 SHO/VMAX Series

Technical Specs

Product Type
Water Pump Oil Seal
Installation
Stacked (two seals)
Dimensions
I.D. 27mm, O.D. 43.25mm, Width 7mm
Housing Material
Rubber
Housing Color
Black
Seal Type
S-Type oil seal designed for water pump application

What’s in the Box

  • 2 x Water Pump Oil Seals (replaces 93101-28M16-00)

Installation Notes

  1. Disconnect the battery and safely remove the lower unit from the outboard.
  2. Disassemble the water pump housing to access the old oil seals.
  3. Carefully pry out the two old seals, noting their orientation. Clean the seal bore thoroughly, removing any corrosion or debris.
  4. Press the first new seal into the housing.
  5. Install the second seal directly on top of the first, creating a stacked pair. Ensure both are seated evenly and at the correct depth.
  6. Lightly grease the driveshaft and seal lips before reassembling the water pump and installing the lower unit.

Troubleshooting & FAQ

How do I know if these seals are correct for my engine?

First, check the Engine & Model Compatibility table on this page. If your model and year appear, this part is a likely fit. For 100% certainty, always verify the OEM part number (93101-28M16-00) against your engine's service manual or parts diagram before ordering.

Why are two seals included and how are they installed?

These seals are designed for a "stacked" installation where two are used together in the water pump housing. This provides a redundant barrier against water intrusion into the gearcase. They must be installed correctly, often back-to-back, to function properly.

What are the signs of a failing water pump oil seal?

The most common symptom is finding water in your lower unit gear lube, which will often make the oil look milky or cloudy. You might also see a slight oil or water leak from the weep hole on the leg of the outboard just above the lower unit.

How often should these seals be replaced?

It is best practice to replace these oil seals every time you service your water pump impeller, which is typically recommended every 1-2 years or 100-200 hours, depending on operating conditions (especially in saltwater).

Is this an original Yamaha OEM part?

This listing is for an aftermarket replacement, not an OEM component. It has been manufactured in an ISO 9002 facility to meet or exceed OEM specifications using comparable materials and is batch-inspected for quality and consistency.

How long does shipping take and what does it cost?

We ship worldwide quickly, with a typical transit time of 5–15 days for most regions. Standard shipping is free. If available for your location, expedited shipping options and their costs will be presented at checkout.

What is the warranty and return policy?

This product is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter an issue, please contact our support team with your order details. Returns are accepted within our standard window for items that are unused and in their original condition. See our full policy page or reach out for instructions.

Safety & Important Info

  • Verify images and specifications against your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement part, not an original equipment (OEM) component.
  • Professional installation is recommended for safety and performance. Incorrect installation can lead to engine damage.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and rigorously tested for real-world reliability.
  • Fast Global Fulfillment — With free standard delivery to most regions, you can expect your parts to arrive in 5–15 days.
  • Manufacturer-Direct Value — We offer fair, transparent pricing by removing middlemen, without ever compromising on materials or quality control.

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