8134351 Plug Assy-Reservoir for Mercury Mercruiser | JLM Marine

Plug Assy-Reservoir for Mercury Mercruiser Outboard Motors (8134351)

This Plug Assembly-Reservoir is designed specifically for Mercury Mercruiser outboard motors ranging from 75HP to 125HP. It serves as a critical trim motor accessory, ensuring proper reservoir function and reliable trim system operation in your outboard engine.

This aftermarket replacement directly crosses to OEM part numbers 22-813435 and 8134351, providing a cost-effective solution for maintaining your Mercury Mercruiser trim system without compromising on quality or performance.

• Sold as a set of 2 plugs for complete reservoir service
• Direct fit for Mercury Mercruiser Quicksilver 75hp-125hp outboard motors
• Includes all components shown in product images

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

Each kit includes:

• Plug 22-8134351 × 2 pieces

Note: The package contains all the parts shown in the product images.

Installation Guide

1. Ensure the engine is turned off and cooled down completely before starting any work on the trim system.
2. Locate the reservoir on your Mercury Mercruiser trim motor assembly and identify the existing plug assemblies.
3. Carefully remove the old plug assemblies from the reservoir, taking care not to damage the reservoir housing threads.
4. Inspect the reservoir openings for any debris, corrosion, or damage; clean thoroughly if necessary.
5. Check the new plug assemblies to ensure they match the original parts in size and thread configuration.
6. Apply a small amount of marine-grade thread sealant to the threads of the new plug assemblies if recommended by your service manual.
7. Hand-tighten the new plug assemblies into the reservoir openings, ensuring proper alignment and seating.
8. Use an appropriate wrench to snug the plugs to the manufacturer's recommended torque specification; avoid over-tightening.
9. Inspect the installation for proper fit and ensure there are no gaps or cross-threading.
10. Refill the trim system with the appropriate hydraulic fluid if any fluid was lost during the procedure.
11. Test the trim motor operation through its full range of motion to verify proper function and check for any leaks.
12. Re-inspect the plug assemblies after initial use and retighten if necessary following your first outing.

Troubleshooting & FAQ

Q: How do I confirm this plug assembly fits my Mercury outboard?
A: Verify your engine's HP rating falls within the 75HP-125HP range and cross-reference the OEM part numbers 22-813435 or 8134351 with your service manual or parts diagram. You can also use the Mercury Serial Number Guide linked above to identify your exact model.

Q: What are the signs that my reservoir plugs need replacement?
A: Common indicators include hydraulic fluid leaks around the plug area, difficulty maintaining trim position, erratic trim motor operation, or visible corrosion and damage to the existing plugs. If you notice any fluid seepage, replace the plugs immediately.

Q: Can I reuse the old plugs if they appear undamaged?
A: While visually intact plugs may seem reusable, the sealing surfaces can degrade over time from exposure to hydraulic fluid and heat cycles. For reliable long-term performance and to prevent future leaks, we recommend replacing them with new parts during trim system maintenance.

Q: Do I need any special tools to install these plug assemblies?
A: Basic hand tools are typically sufficient—you'll need an appropriately sized wrench or socket to remove the old plugs and install the new ones. A torque wrench is recommended to ensure proper tightening without over-torquing and damaging the reservoir threads.

Q: What's the difference between OEM and aftermarket plugs?
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.