Sierra 18-7811 Fuel Pump Kit, Replaces Mercury Marine 89031A1, for Mercury/Mariner Outboard Motors

The Sierra 18-7811 Fuel Pump Kit is a replacement fuel pump rebuild kit designed for Mercury and Mariner outboard motors. It is built to restore proper fuel delivery on outboards using the original Mercury Marine 89031A1 fuel pump, giving boat owners a straightforward way to replace worn pump components without sourcing a full new pump assembly.

The kit includes the O-rings needed to properly seal the fuel pump during a rebuild, specifically O-Ring 18-7411 and O-Ring 18-7120. These sealing components are critical to preventing fuel leaks and maintaining consistent fuel pressure once the pump is reinstalled. Because fuel pump kits are fit specific, buyers should confirm part numbers against their existing pump before ordering to ensure proper fit.

This kit is intended as a direct equivalent to the OEM Mercury Marine 89031A1 fuel pump kit, and is cross-referenced to several other aftermarket part numbers for buyers searching by a different brand's catalog number. It ships as a single kit unit, making it a compact, low-cost solution for routine outboard fuel system maintenance.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-7811
• Category: Mercury Outboard Fuel Pump Kit
• Included Components: O-Ring 18-7411, O-Ring 18-7120
• Weight: 0.03 pounds
• Item Dimensions: 0.39 x 0.39 x 0.39 inches
• Unit Count: 1 kit
• UPC: 030999322968

Fitment

• Mercury outboard motors
• Mariner outboard motors

Replaces (OEM)

• Mercury Marine 89031A1
• Mercury 66599A1
• GLM 40350
• Mallory 9-37756

Frequently Asked Questions

What is included in the Sierra 18-7811 Fuel Pump Kit? The Sierra 18-7811 Fuel Pump Kit includes O-Ring 18-7411 and O-Ring 18-7120, the sealing components needed to rebuild a Mercury/Mariner outboard fuel pump.

Which outboard motors does the Sierra 18-7811 fit? This kit is designed for Mercury and Mariner outboard motors. Since fuel pump kits are fit specific, confirm the existing pump's part number before ordering.

Does the Sierra 18-7811 replace the Mercury Marine 89031A1 fuel pump? Yes, the Sierra 18-7811 Fuel Pump Kit is a direct equivalent to the Mercury Marine 89031A1 fuel pump kit.

Are there other part numbers that cross-reference to the Sierra 18-7811? The Sierra 18-7811 is interchangeable with Mercury 66599A1, GLM 40350, and Mallory 9-37756.

How much does the Sierra 18-7811 Fuel Pump Kit weigh? The kit weighs 0.03 pounds, making it a lightweight, compact rebuild kit.

What are the dimensions of the Sierra 18-7811 kit packaging? The Sierra 18-7811 Fuel Pump Kit measures 0.39 x 0.39 x 0.39 inches.

Is the Sierra 18-7811 an OEM or aftermarket part? The Sierra 18-7811 is an aftermarket kit manufactured to match the specifications of the OEM Mercury Marine 89031A1 fuel pump.

How many units come in one Sierra 18-7811 kit? Each Sierra 18-7811 Fuel Pump Kit is sold as a single kit containing one set of O-rings (18-7411 and 18-7120).

Will the Sierra 18-7811 kit stop fuel leaks from my outboard's fuel pump? Replacing worn O-rings with the ones in the 18-7811 kit, O-Ring 18-7411 and O-Ring 18-7120, is intended to restore a proper seal and address leaks caused by degraded pump gaskets.

Can I use the Sierra 18-7811 kit on a Mariner outboard as well as a Mercury? Yes, the Sierra 18-7811 Fuel Pump Kit is designed to fit both Mercury and Mariner outboard motors that use the corresponding fuel pump.