Mercury – High-Volume Water-Separating Fuel Filter | Remote Mount Systems | 35-8M0079963

Overview

This filter is the typical spin-on canister you’ll find on remote-mounted fuel systems, and it’s one of those “don’t skip it” maintenance items. Its job is pretty simple—keep water and fine debris out of the fuel before it reaches anything important. What makes this one stand out is the extra filtering material inside, so it can handle heavier fuel demand without choking things up. Swapping it out takes almost no effort: twist off the old one, wipe the flange, and screw on the new canister.

Key Features

 • 10-Micron Filtration – Grabs the small debris that tends to cause rough running.
 • High-Volume Capacity – Can move up to 120 gallons an hour without fuel starvation.
 • Extra Filter Surface – Has more media than many aftermarket filters.
 • Built-In Water Separation – Helps keep moisture from getting into the fuel system.
 • Simple Spin-On Change – Quick seasonal replacement with basic tools.

Engine & Boat Compatibility

 • Outboards with remote-mounted filters
 • Sterndrive engines
 • Inboard engines
 • Systems with normal clearance around the filter housing

Performance & Practical Benefits

A new filter often smooths out little quirks you might’ve gotten used to—hesitation when you hit the throttle, a slight stumble at idle, or that uneven feel at midrange. Removing water helps the motor burn cleaner and keeps fuel economy from dipping. It’s a small part, but it prevents a surprising amount of fuel-related issues over the course of a season.

Why Buy OEM

Mercury designs these filters to match the fuel volume and filtration level their engines expect. The canister holds up to vibration, ethanol blends, and long days on the water better than bargain filters. And the water-separating layer isn’t just “marketing”—it actually pulls moisture out of the fuel before it gets to the engine.

FAQ

Q1: How often should I replace this filter?
Once a season is a good rule of thumb, sooner if the engine starts feeling sluggish.

Q2: Should I pre-fill it before installing?
Most people don’t—just oil the gasket and spin it on snug.

Q3: Is it fine for saltwater boats?
Yes. Just stay consistent with your yearly changes.

Q4: How do I get the old one off if it’s stuck?
A strap wrench usually does the trick. Keep a rag handy—it’ll drip a little.

Q5: What happens if I skip replacing it?
You may see hesitation, rough idle, or stalling under load—classic signs of restricted flow or water contamination.