Mercury Marine Qualifies for Free Shipping Mercury Diaphragm Kit #55278A5

Mercury Diaphragm Kit #55278A5

$10.69

Mercury Diaphragm Kit #55278A5

$10.69

Mercury Diaphragm Kit #55278A5

$10.69

SKU: MRC-55278A5

UPC: 745061159846

Category: Fuel Pumps

More about this item

Mercury Marine 55278A5 Fuel Pumps

The Mercury Marine Diaphragm Kit #55278A5 is a genuine OEM rebuild kit designed to restore your Mercury fuel pump to factory performance. The diaphragm is the heart of a mechanical fuel pump — as it flexes with each engine cycle, it draws fuel from the tank and pushes it to the carburetor or fuel system. Over time, heat, ethanol-blended fuels, and normal wear cause the diaphragm to crack, harden, or lose flexibility, leading to fuel delivery problems that can leave you stranded on the water.

Replacing the diaphragm with this authentic Mercury kit is a cost-effective alternative to purchasing an entirely new fuel pump. Common symptoms of a failing diaphragm include fuel leaks, hard starting, engine stumbling at speed, and fuel starvation under load — all of which this kit directly addresses. Because it's a genuine Mercury Marine part, you get the exact material composition and dimensional tolerances required for a proper seal and long service life.

Lightweight and easy to install for anyone comfortable with basic engine maintenance, the #55278A5 kit is an essential item to keep on hand for routine fuel pump servicing. Proactive replacement during scheduled maintenance can prevent unexpected breakdowns and keep your Mercury engine running strong all season long.

Normalized SKU: 55278A5
UPC Code: 745061159846

Qualifies for Free Shipping
This item qualifies for free shipping when the order is over $149
$10.69
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