Fuel Pump Diaphragm Kit for Mercury Mariner Outboard Sport Jet 857005A1 18-7817

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£21.99

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Fuel Pump Diaphragm Kit 857005A1

Name: Fuel Pump Diaphragm Kit for Mercury Mariner Outboard Sport Jet 857005A1 18-7817
Price: 21.99 GBP
Rating: 5 (1 reviews)

Premium Quality Replacement for Mercury & Mariner Outboards

Is your outboard engine hesitating, stalling, or struggling to start? This 12-piece fuel pump diaphragm rebuild kit is designed to restore consistent fuel delivery and engine response. Engineered to meet or exceed original equipment standards, this kit provides a cost-effective solution to common fuel system issues caused by worn or stiffened diaphragms.

RELIABILITY: Manufactured with marine-grade materials to withstand ethanol-blended fuels and harsh saltwater environments.

Key Features

✔ Direct fit for Mercury/Mariner 30HP-250HP
✔ Complete 12-piece rebuild kit
✔ Corrects hard starting and rough idling
✔ High-grade ethanol-resistant diaphragms

Technical Specs

Kit Contents:	12 Pieces
Includes:	Diaphragms, Gaskets, Valves, Spring, Screws
Engine Type:	2-Stroke Outboard / Sport Jet
Material:	Viton/Marine Grade Gasket Material

Compatibility / Fitment Guide

Engine Series	Horsepower / Models	Note
Mercury/Mariner 2-Stroke	30HP, 35HP, 40HP, 45HP, 50HP, 55HP, 60HP	Check Serial Range
Mercury/Mariner 2-Stroke	75HP, 90HP, 100HP, 115HP, 125HP	3 & 4 Cylinder Models
Mercury V-Block	V-135, V-150, V-175, V-200, V-225, V-250	Carbureted & EFI
Mercury Sport Jet	90, 95XR, 120, 175XR2	Jet Drive Pump

OEM Cross Reference

Mercury / Quicksilver:	857005A1, 21-857005A1
Sierra Marine:	18-7817
GLM:	40290
Mallory:	9-35430

Questions & Answers

Is this a genuine original part?

This is a premium quality aftermarket replacement part, manufactured to meet or exceed original equipment (OE) standards for fitment and performance on Mercury engines.

How do I know if it is compatible?

We recommend checking the SKU/MPN and Cross Reference list provided above. This kit specifically fits Mercury/Mariner 2-stroke engines that utilize a diaphragm-style fuel pump.

Will this fix my engine's stalling issues?

If your engine stalls due to fuel starvation or a loss of fuel pressure, a worn or torn diaphragm is often the cause. This kit replaces those critical components to restore proper suction and pressure.

Note: Please verify your original part number or engine serial number against the references above before purchasing. Domain: 4boats.co.uk

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Fuel Pump Diaphragm Kit for Mercury Mariner Outboard Sport Jet 857005A1 18-7817