Carburetor Rebuild Kit – Fits Mercury/Mariner 40-150 HP (Replaces 1395-5109-1, 18-7021)

Carburetor Rebuild Kit – Fits Mercury/Mariner 40-150 HP (Replaces 1395-5109-1, 18-7021)

This rebuild kit is designed for Mercury and Mariner outboard engines from 40-150 HP, specifically 2-stroke models manufactured between 1976–1990 with designated WMK series carburetors.

This kit is a direct replacement for Mercury OEM parts 1395-5109 and 1395-5109-1, as well as Sierra 18-7021, GLM 40480, and Pro Marine 7021.

• Complete Service Kit: Includes all standard components like gaskets, O-rings, and needle valve assembly to overhaul a single carburetor.
• Fuel Type: Compatible with standard gasoline.
• Installation: Engineered as a direct replacement part for a straightforward service.

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

• 1 × Carburetor Rebuild Kit (1395-5109-1) for a single carburetor, which includes:
  • Gaskets
  • O-rings
  • Needle valve assembly
  • Float pivot pin
  • Other components for a single carburetor service

Important: This kit services one carburetor. For engines with multiple carburetors, you must purchase one kit per carburetor.

Installation Guide

1. Turn off the engine and shut off the fuel supply. Disconnect the boat's battery for safety.
2. Carefully disconnect fuel lines and any linkages attached to the carburetor, noting their orientation for reassembly.
3. Remove the mounting nuts or bolts and take the carburetor off the engine.
4. Working on a clean bench, disassemble the carburetor. Keep parts organized and take photos if needed.
5. Clean all metal parts with a dedicated carburetor cleaner. Never spray cleaner on non-metal components like gaskets or O-rings.
6. Use the new parts from the kit to replace the old gaskets, seals, O-rings, and the needle valve assembly.
7. Reassemble the carburetor, ensuring the float is set to the correct height as per your engine's service manual.
8. Mount the rebuilt carburetor back onto the engine and tighten the fasteners to the specified torque.
9. Reconnect the fuel lines and linkages.
10. Turn the fuel supply back on and check for any leaks.
11. Start the engine, check for smooth operation, and adjust the idle mixture and speed if necessary.

Troubleshooting & FAQ

Q: How do I confirm this kit fits my specific engine?
A: This kit is for Mercury/Mariner 40-150 HP 2-stroke engines (1976-1990) that use WMK series carburetors. Please consult the "Compatible Engine Models" table above and cross-reference your engine's specific WMK model code (e.g., WMK-3, WMK-21) to ensure a match.

Q: How many kits do I need for my engine?
A: This kit contains parts to rebuild one carburetor. If your engine has three carburetors, you will need to purchase three kits to fully service the fuel system.

Q: What are the signs my carburetor needs rebuilding?
A: Common symptoms of a failing carburetor include difficulty starting, rough or erratic idling, stalling at low speeds, poor acceleration, black smoke from the exhaust, and visible fuel leaks from the carburetor body.

Q: OEM vs. 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.