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 carburetor rebuild kit is designed for Mercury/Mariner 40-150 HP, 2-Stroke outboard engines (1976–1990) equipped with WMK series carburetors. It provides the necessary components to restore a single carburetor to optimal function.

This kit is a direct replacement for Mercury part numbers 1395-5109-1 / 1395-5109, Sierra 18-7021, GLM 40480, and Pro Marine 7021.

• Engineered for direct OEM-replacement service.
• Compatible with standard gasoline fuel.
• Includes all standard components for servicing one carburetor.

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 package contains one (1) Carburetor Rebuild Kit for servicing a single carburetor. If your engine has multiple carburetors, you must purchase one kit for each.

• Gaskets
• O-rings
• Needle valve assembly
• Float pivot pin
• Other components for a complete service

Installation Guide

1. Safety First: Disconnect the battery and ensure the fuel supply line is shut off.
2. Remove Carburetor: Carefully detach the fuel lines and linkages, then remove the carburetor from the engine.
3. Disassembly: On a clean workbench, disassemble the carburetor. Keep track of all parts and their orientation.
4. Cleaning: Use a quality carburetor cleaner to clean all metal components thoroughly. Do not immerse rubber or plastic parts in the cleaner.
5. Inspect Parts: Check for any wear or damage on parts not included in the kit, such as the float or jets.
6. Install New Components: Carefully remove the old gaskets, seals, and needle valve. Install the new parts from the kit.
7. Reassembly: Reassemble the carburetor, making sure all gaskets are properly seated and screws are tightened to the correct torque.
8. Reinstall & Adjust: Mount the carburetor back on the engine, reconnect all lines and linkages, and turn the fuel supply back on.
9. Test & Tune: Start the engine and check for leaks. Adjust the idle speed and air/fuel mixture screws as per your engine's service manual for smooth operation.

Troubleshooting & FAQ

How do I confirm this kit fits my engine?
First, check the compatibility table on this page. This kit fits Mercury/Mariner 40-150 HP 2-Stroke outboards (1976-1990) with WMK series carburetors. Second, cross-reference your carburetor's part number with the numbers listed in the "Part Number Cross-Reference" table.

How many carburetors does this kit service?
This kit contains all the necessary components to rebuild one single carburetor. If your engine has two or more carburetors, you will need to purchase one kit for each to ensure a complete and balanced service.

What are common signs that my carburetor needs to be rebuilt?
Common symptoms include difficulty starting, rough idling, stalling at low speeds, black smoke from the exhaust, engine hesitation, or visible fuel leaks from the carburetor body. A rebuild can often restore performance and efficiency.

OEM vs. Aftermarket?
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.

How fast do you ship and how much does it cost?
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.

What is your warranty and return policy?
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.