FUSCH Electric Low-Pressure Fuel Pump for Mercury Mercruiser 4.3L/5.0L/5.7L Carbureted Engines — 8–10 PSI, OEM-Style Fit

FUSCH Electric Low Pressure Fuel Pump is a direct replacement fuel pump designed for carbureted Mercury Mercruiser V6 and V8 marine engines, delivering 8–10 PSI for reliable low-pressure fuel delivery. This replacement pump is engineered to meet OEM-style fit and function for older Mercruiser carbureted outboards and sterndrives. Built from metal and ABS components and supplied with sealing washers and an electrical connector, it’s intended for owners who need a dependable, budget-friendly swap for worn or leaking low-pressure pumps on 4.3L, 5.0L and 5.7L engines.

Which Mercury engines and part numbers does this pump replace?

The pump is formulated for specific carbureted Mercury Mercruiser applications and fits common aftermarket and OEM part numbers. It offers a compatible substitute for older low-pressure fuel systems.

• Fits Mercruiser 4.3L (262) 1998, 5.0L (305) 2000, and 5.7L (350) 2000 carbureted engines.
• Replaces part numbers: Mercruiser 861155A3, Mallory 935432, Sierra 18-8868, and 861155A2.
• Suitable for MCM/MIE 4.3L V6 and 5.0L V8 Gen+ applications and some 350 ci carb setups.

How do I know this pump is right for my carbureted engine?

Confirm compatibility by matching engine type, year, and the original pump’s part number. This unit is for low-pressure, carburetor-fed fuel systems only and differs from fuel-injection pumps in nozzle and mounting details.

• Works only with carbureted engines—does not fit fuel-injected systems.
• Pump outlet small end is threaded; fuel-injection pumps typically are not threaded there.
• Provides approximately 8–10 PSI, appropriate for carburetor float bowls and mechanical fuel regulators.

What are the build and included accessories?

The FUSCH pump uses durable metal and ABS parts and arrives ready to install with common hardware. It’s packaged to simplify replacement and reduce the need for extra parts when swapping out an old pump.

• Housing and moving parts made from metal and ABS for corrosion resistance and strength.
• Includes tight-seal washers and an electrical connector plug for wiring compatibility.
• Manufactured to OEM-style dimensions to ease bolt-on installation on approved engines.

What should I watch for during installation and use?

Follow safe marine fuel-handling practices and verify that the fuel system matches low-pressure carburetor requirements. Improper use on fuel-injected engines can cause performance issues or damage.

• Do not install on fuel-injected engines—this pump lacks injection-compatible fittings and pressure.
• Check electrical connections, ground, and fuse sizing to protect the pump circuit.
• Inspect inlet/outlet fittings and hoses for proper size and secure clamps to prevent leaks.

This FUSCH low-pressure electric fuel pump is for boat owners and marine technicians maintaining classic or carbureted Mercruiser engines who need an economical, OEM-compatible replacement. It’s ideal if your engine uses the listed part numbers and requires 8–10 PSI fuel delivery; if your craft has fuel injection or a different pressure spec, choose a pump designed for that system instead.

FAQ

Q: Can this pump be used on fuel-injected Mercury engines?

A: No. This FUSCH pump is a low-pressure 8–10 PSI unit for carbureted engines and is not compatible with fuel-injection systems.

Q: Which part numbers does this replace?

A: It replaces Mercruiser 861155A3, Mallory 935432, Sierra 18-8868 and 861155A2 for compatible carbureted models.