Sierra Fuel Pump Kit 18-7818-1 for Mercury 115 HP 4 Cyl Outboards, Replaces 42909A3, 42909A4

The Sierra Fuel Pump Kit 18-7818-1 is a direct-fit replacement fuel pump kit built for Mercury 115 HP (4 cylinder) outboards with engine serial number B209468 and up. It restores reliable fuel delivery from tank to carburetor on applicable Mercury 4-cylinder powerheads, giving you an OE-specification alternative to the original Mercury Marine fuel pump kit at the point where age or wear causes weak fuel pressure, hard starting, or rough running.

The kit is built with a metal body and uses hose barb connections, with a hose barb inlet fitting and a barb-style outlet fitting, each sized at 1.27 centimeters, for compatible fuel line hookup. It is designed for gasoline fuel systems. Sierra parts in this line are noted as meeting OE specification, so installers can expect the same fit, form, and function as the original Mercury Marine components it replaces.

Because this kit is application-specific to the 115 HP 4-cylinder Mercury outboard with the stated serial number cutoff, confirm your engine's HP rating and serial number against the listed range before ordering to ensure correct fitment.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-7818-1
• Category: Fuel Pump Kit
• Fitment: Mercury 115 HP (4 Cylinder) outboards, engine serial number B209468 and up
• Replaces (OEM): Mercury Marine 42909A3, 42909A4
• Material: Metal
• Item Dimensions: 0.39 x 0.39 x 0.39 inches
• Weight: 0.02 pounds
• Inlet Connection Type: Hose Barb
• Inlet Connection Size: 1.27 centimeters
• Outlet Connection Type: Barb
• Outlet Connection Size: 1.27 centimeters
• Gas Type: Gasoline

Fitment

• Mercury 115 HP (4 Cylinder) outboards, engine serial number B209468 and up

Replaces (OEM)

• Mercury Marine 42909A3
• Mercury Marine 42909A4

Frequently Asked Questions

What does the Sierra 18-7818-1 fuel pump kit fit? The Sierra 18-7818-1 fuel pump kit fits Mercury 115 HP outboards with a 4-cylinder engine, specifically units with engine serial number B209468 and up.

Is 18-7818-1 a direct replacement for the Mercury OEM fuel pump kit? Yes, 18-7818-1 replaces Mercury Marine OEM fuel pump kits 42909A3 and 42909A4 and is built to meet OE specification for fit and function.

What OEM part numbers does this kit cross-reference? This Sierra kit crosses over to Mercury Marine part numbers 42909A3 and 42909A4.

How do I know if my Mercury 115 HP outboard uses this fuel pump kit? Check your engine's serial number: the 18-7818-1 kit applies to Mercury 115 HP 4-cylinder outboards with engine serial number B209468 or higher.

What material is the 18-7818-1 fuel pump kit made of? The fuel pump kit body is made of metal.

What size are the inlet and outlet connections on this fuel pump kit? Both the inlet (hose barb) and outlet (barb) connections on the 18-7818-1 kit measure 1.27 centimeters.

How much does the Sierra 18-7818-1 fuel pump kit weigh? The kit weighs 0.02 pounds.

What fuel type is this fuel pump kit designed for? The 18-7818-1 fuel pump kit is designed for gasoline fuel systems.

What are the dimensions of the fuel pump kit? The kit measures 0.39 x 0.39 x 0.39 inches.

Will this fuel pump kit fit a 6-cylinder Mercury outboard? No, the 18-7818-1 kit is designated specifically for the Mercury 115 HP 4-cylinder outboard application listed, not other cylinder configurations.

Does the Sierra fuel pump kit meet OE specifications? Yes, the 18-7818-1 kit is noted as meeting OE specification, matching the performance of the original Mercury Marine parts it replaces.