17-95372 18-95295 12-8035161 26-95348 25-16131 27-95220 Prop Shaft Seal Kit with Shear Pin for Mercury Mariner 2.5HP 3.3HP | JLM Marine

Prop Shaft Seal Kit with Shear Pin – Fits Mercury Mariner 2.5HP & 3.3HP Outboard Motors

This comprehensive prop shaft seal kit is designed for Mercury Mariner 2.5HP and 3.3HP 4-stroke outboard engines with serial number 0R131842 or higher. It provides all the essential seals, gaskets, and pins needed to service your lower gearcase unit and maintain optimal propeller shaft performance.

This kit directly replaces OEM part numbers 17-95372, 18-95295, 12-8035161, 26-95348, 25-16131, and 27-95220, offering a complete solution for lower unit maintenance in a single package.

• Includes oil seal, gaskets, o-ring, shear pins, and cotter pin for complete lower unit service
• Compatible with Mercury Mariner 4-stroke outboards (serial 0R131842+)
• Direct replacement for multiple OEM part numbers

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here's a guide to help you identify your engine's serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Technical Specifications

Package Contents

This comprehensive kit includes all components needed for lower unit prop shaft service:

• 2 x Shear Pin (17-95372)
• 1 x Cotter Pin (18-95295)
• 1 x Oil Seal (26-95348)
• 1 x Gasket (12-8035161)
• 1 x O-ring (25-16131)
• 2 x Drain Gasket (27-95220)

Installation Guide

1. Preparation: Disconnect the spark plug wire and remove the propeller nut and washer. Inspect the old cotter pin and remove it carefully.
2. Remove Propeller: Slide the propeller off the shaft. Check for fishing line or debris around the shaft and clean thoroughly.
3. Inspect Shear Pin: Examine the existing shear pin for damage or shearing. If broken, remove both halves completely from the prop shaft.
4. Replace Oil Seal: Carefully pry out the old oil seal from the lower unit housing using a seal puller or flat tool. Clean the seal bore and press in the new seal evenly until seated.
5. Install Gaskets & O-ring: Remove old drain gaskets and install new ones on drain/fill plugs. Replace the o-ring as needed during lower unit service.
6. Install New Shear Pin: Align the propeller hub with the shaft and insert the new shear pin through the aligned holes. Ensure it passes completely through both sides.
7. Reinstall Propeller: Slide the propeller back onto the shaft, ensuring the shear pin is properly seated. Install the washer and propeller nut.
8. Secure with Cotter Pin: Insert the new cotter pin through the propeller nut castle slots and shaft hole. Bend the pin ends outward to lock in place.
9. Final Check: Verify all components are tight and secure. Rotate the propeller by hand to ensure smooth operation with no binding.
10. Reconnect & Test: Reconnect the spark plug wire. Test the engine in a controlled environment before full operation.

Troubleshooting & FAQ

Q: How do I know if my shear pin is damaged?
A: If your propeller spins freely without engaging forward/reverse thrust, or if you hear unusual rattling from the lower unit, the shear pin has likely sheared. Remove the propeller to inspect—a broken pin will be visibly damaged or missing.

Q: How often should I replace the seals and gaskets in this kit?
A: Replace the oil seal and gaskets during routine lower unit service (typically every 100 hours or annually). Replace shear pins immediately when broken, and inspect drain gaskets whenever changing lower unit oil.

Q: Will this kit fit Mercury Mariner 2-stroke engines?
A: No, this kit is specifically designed for 4-stroke Mercury Mariner 2.5HP and 3.3HP engines with serial number 0R131842 or higher. Verify your engine model and serial number before purchasing.

Q: What's the difference between the shear pins included and OEM pins?
A: These aftermarket shear pins are manufactured to OEM specifications with comparable materials and shear strength. They provide the same protective function—breaking under impact to prevent costly lower unit damage.

Q: Can I reuse the old cotter pin?
A: No, cotter pins should never be reused. Once bent, they lose their structural integrity and may fail to secure the propeller nut properly, creating a safety hazard.

Q: Is this an OEM product or aftermarket?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.