Yeoflagtrade Mercury Fuel Pump Replacement 861155A3 Low-Pressure for 4.3L/5.0L/5.7L Carbureted Engines Dual-Line

Yeoflagtrade 861155A3 is a low-pressure electric replacement fuel pump engineered to fit Mercury/MerCruiser 4.3L, 5.0L and 5.7L carbureted marine V6 and V8 engines.

This replacement pump is built to restore consistent fuel delivery to older marine engines that use a low-pressure carbureted fuel system. It replaces common OE part numbers including 861155A3, 861155-2, 935432 and 18-8868, offering a direct-fit option for many late‑1990s and early‑2000s Mercury Marine applications. The unit’s dual-line layout and durable construction make it a practical service part for inboard/outboard and sterndrive vessels where reliable fuel flow is needed for starting and cruising.

Which Mercury engines will this pump work with?

This pump is intended for carbureted Mercury MerCruiser engines, primarily from the late 1990s and 2000s. Typical fits include 4.3L V6 (262 ci) and larger 5.0L and 5.7L V8 (305/350 ci) models that used a low-pressure fuel pump configuration from the factory.

• Compatible with 4.3L V6, 5.0L V8 and 5.7L V8 carburetor engines.
• Direct replacement for OE numbers 861155A3, 861155-2, 935432 and 18-8868.
• Designed for MCM/MIE Gen+ and many 350 ci carbureted applications.

How does this pump help with starting and running reliability?

The pump restores steady low-pressure fuel flow to the carburetor, which reduces hard starts and erratic idling caused by weak or failing pumps. Improved delivery helps stabilize engine performance during warm-up and under light to moderate loads.

• Dual-line design mimics factory transfer-style flow for consistent fuel supply.
• Replaces worn pumps that cause vapor lock or slow starts.
• Engineered for long service life to minimize repeat replacements.

What should I check before ordering to ensure correct fit?

Confirm model year, engine displacement, and whether your engine uses a carburetor with a low‑pressure pump. Compare your current pump’s part number with the interchange list and inspect mounting and electrical connector styles to verify compatibility.

• Match original part numbers: 861155A3, 861155-2, 935432, 18-8868.
• Verify engine type: carbureted 4.3L V6, 5.0L/5.7L V8 models.
• Check physical mount, inlet/outlet hose sizes, and electrical connector shape.

What are the design and durability highlights?

The unit is built with robust materials and tested to provide extended service life under marine conditions. Its construction focuses on resisting the vibration and corrosion common in boating environments and sustaining thousands of hours of operation.

• Durable engineering targeted for long operational life.
• Corrosion- and vibration-resistant build suitable for marine use.
• Dual-line layout and transfer-style configuration for reliable flow.

Who is this for: boat owners, mariners, and marine technicians seeking a cost-effective, direct-replacement fuel pump for older Mercury MerCruiser carbureted engines. It’s a practical choice for those maintaining 4.3L V6 and 5.0L/5.7L V8 boats who need to restore dependable low-pressure fuel delivery without altering the original fuel system. Always confirm fitment with your engine’s model year and part number list before purchase.