Fuel Pump Kit – Fits Mercury Mariner 30-275 HP and Force 40-150 HP Outboards (Replaces 43990A10, 857005A1, 18-7817)

Fuel Pump Kit – Fits Mercury Mariner 30-275 HP and Force 40-150 HP Outboards

This fuel pump rebuild kit is designed for a wide range of Mercury/Mariner (30–275 HP) and Force (40–150 HP) 2-stroke outboard engines. It provides a reliable solution for restoring fuel system performance and addressing issues caused by worn or damaged diaphragms and gaskets.

Engineered to meet OEM specifications, this kit serves as a direct replacement for multiple part numbers, ensuring a precise fit for compatible fuel pump assemblies. Please verify your engine model and original part number against the cross-reference tables below before ordering.

• Installation Type: Direct replacement rebuild kit for the OEM assembly.
• Compatible Fuel Type: Designed for use with standard gasoline.
• Complete Kit: Includes all necessary diaphragms, gaskets, check valves, and hardware for a full rebuild.

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.

Confirm your engine model/year in the table below.

Mercury/Mariner Outboards

Force Outboards

Technical Specifications

Package Contents

• 1 x Fuel Pump Kit, which includes: diaphragms, gaskets, check valves, spring, cap and screws.

Installation Guide

Follow these general steps to rebuild your fuel pump with this kit. Always consult your engine's service manual for detailed instructions specific to your model.

1. Safety First: Disconnect the battery and work in a well-ventilated area away from sparks or open flames.
2. Access the Pump: Locate and remove the fuel pump assembly from the engine block. Note the position of all fuel lines and fittings.
3. Disassemble the Pump: Carefully remove the screws holding the pump housing together. Lay out all parts on a clean cloth in the order they were removed.
4. Inspect and Clean: Clean all metal components with a suitable solvent and inspect the housing for cracks or damage.
5. Install New Components: Replace the old diaphragms, gaskets, and seals with the new parts from the kit. Ensure each component is correctly oriented.
6. Reassemble the Pump: Carefully reassemble the pump housing, ensuring gaskets are aligned. Tighten screws in a star pattern to the manufacturer's recommended torque.
7. Reinstall and Test: Mount the rebuilt pump back on the engine, reconnect all fuel lines, and reconnect the battery. Prime the fuel system and check for leaks before starting the engine.

Troubleshooting & FAQ

How do I confirm this kit fits my specific engine?
The best way is to match your original fuel pump's part number to the ones listed in our "Part Number Cross-Reference" table. Additionally, check your engine's horsepower, and brand against our "Compatible Engine Models" list.

What are common symptoms of a failing fuel pump diaphragm?
Signs include the engine bogging down at high speeds, difficulty starting, rough idling, or visible fuel leaks from the pump housing. A worn diaphragm can also allow fuel to leak into the crankcase, so check your oil for a gasoline smell.

Is this a complete kit for a full rebuild?
Yes, this kit includes the essential components typically needed to rebuild a compatible fuel pump, such as diaphragms, gaskets, check valves, and hardware. It is designed to restore the pump to its original operating condition.

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.