Mercury – Fuel Line Assembly | Fuel System | Gray Low-Permeation Hose | 8M0078626

Overview

There’s something reassuring about that first squeeze of the primer bulb the way it firms up smoothly and tells you the engine is ready to wake up without hesitation. It’s a small moment, but you feel it in your whole body when you’re a boater. The Mercury Fuel Line Assembly 8M0078626 is built to deliver that same sense of calm reliability every single time you leave the dock. Whether you’re idling into a quiet canal or heading across open water with a little chop underneath you, this assembly keeps fuel moving clean and steady so the engine can do what it does best — run without drama.

Key Features

• Five-sixteenth-inch inside diameter hose for consistent and reliable fuel flow
• Low-permeation fuel hose helps protect fuel quality and reduce odor
• Mercury-engineered primer bulb offers firm, predictable priming pressure
• Gray outer coating reflects heat to help prevent vapor lock
• Flexible, marine-grade hose designed for long-term sun, weather, and fuel exposure
• Compatible with a variety of tank and engine connector styles
• Great choice for portable tanks, integrated systems, and custom fuel line routing

Engine & Boat Compatibility

• Fits Mercury and Mariner outboards using universal five-sixteenth-inch fuel lines
• Ideal for small to mid-range horsepower engines across many production years
• Perfect for pontoons, runabouts, aluminum fishing boats, skiffs, tenders, and inflatables
• Adapts cleanly to multiple tank types with the appropriate fittings

Performance & Practical Benefits

You’ll feel the difference right away. The primer bulb tightens with that solid, reassuring pressure that tells you fuel is flowing properly. The hose itself bends naturally around corners and through narrow rigging paths without collapsing a small detail that makes a big difference in maintaining smooth, steady flow when the boat shifts through chop or when people move around the deck.

On hot days, when the sun turns the deck into a warm plate, the gray coating helps reflect heat rather than absorb it. That keeps fuel temperatures more stable and lowers the risk of vapor lock during long runs. The low-permeation materials help limit fuel odor and slow evaporation, which is especially helpful if your boat spends stretches of time under a cover or in a shed. Season after season, the hose remains flexible and durable rather than stiffening or cracking, and the primer bulb keeps its clean, firm squeeze. It all adds up to easier starts, smoother idle, and fewer mid-season fuel headaches.

Why Buy OEM

Fuel delivery is one of those areas where genuine parts really matter. Mercury Marine designs everything from the hose blend to the check valves inside the primer bulb to handle real on-the-water conditions. Aftermarket lines often look similar, but they don’t match Mercury’s reliability, long-term durability, or priming performance. Choosing OEM means proper fit, predictable operation, and fewer surprises when you’re miles from the dock. It’s the smart, practical choice for boaters who value smooth, trouble-free time on the water.

FAQ

Q1: Which engines does the 8M0078626 Fuel Line Assembly fit?

It fits Mercury and Mariner outboards that use a universal five-sixteenth-inch fuel line, once matched with the correct tank and engine connectors.

Q2: How is this different from aftermarket assemblies?

Mercury uses better hose materials, stronger primer bulb valves, and engineering tailored for marine use, resulting in better long-term performance.

Q3: How do I know this is the right replacement?

Confirm your system uses a five-sixteenth-inch line and match the required connector types. With proper fittings, this assembly is typically a direct match.

Q4: Can this be used in both saltwater and freshwater?

Yes. It’s designed for dependable performance in either environment.

Q5: Is installation straightforward?

Very. Add the correct connectors, route and secure the hose neatly, and installation is simple for most boaters.