Mercury – Water Separating Fuel Filter Kit | Mercury Racing 450R/500R & V12 Outboards | Complete OEM Fuel Protection System | 8M0166540

Overview

When you’re running the kind of horsepower that Mercury Racing engines deliver, clean fuel isn’t optional — it’s essential. These engines breathe hard, respond instantly and rely on flawless fuel delivery to stay sharp. And when you’re pushing offshore or running a long stretch at speed, you want the confidence that your powerplant is protected from water, debris and everything else that sneaks into today’s fuel supply. The Mercury Marine part number 8M0166540 Water Separating Fuel Filter Kit gives you that peace of mind. It’s a system built for high-performance outboards, designed to keep your engine running smooth, strong and steady no matter what the day brings.

Key Features

• Complete fuel filtration and water-separation system for high-horsepower outboards
• Includes fuel filter, filter base, fittings, plug, water-in-fuel sensor and extension harness
• Designed to remove moisture and contaminants that reduce horsepower and cause engine wear
• Meets U.S. Coast Guard and ABYC H-24 fuel system standards
• Conforms to CFR 183.90 or ISO 10088 fire safety test requirements
• Built to Mercury OEM specifications for maximum protection and reliability

Engine & Boat Compatibility

• Fits Mercury Racing 4.6L V8 450R (serial 1E083006–1E099720)
• Fits Mercury Racing 4.6L V8 500Rhp (serial 1E099432 and up)
• Fits Mercury V12 500–600hp Verado and SeaPro outboards (serial 3B0600047 and up)
• Ideal for offshore center consoles, performance boats, heavy commercial rigs and long-range recreational vessels

Performance & Practical Benefits

High-performance outboards demand perfect fuel delivery — even a small amount of water can steal power, create hesitation or trigger sensor faults. This filter kit is designed to catch moisture before it ever reaches the engine, separating and storing it so you don’t feel a single hiccup at the helm.

You’ll notice the difference on the water. Throttle response feels tight and immediate. Idle stays steady, even after a rough inlet run. And when you push the boat to its stride, you get all the horsepower your engine is built to deliver — not the diminished output that contaminated fuel can cause.

The integrated water-in-fuel sensor adds another layer of reassurance. Instead of guessing, you get a clear alert the moment water levels become a concern. For offshore boaters, that little bit of forewarning can make all the difference between getting home comfortably and dealing with a preventable breakdown.

Installation is straightforward, thanks to the included filter base, fittings and extension harness. Everything is designed to fit neatly and securely, giving you a clean, confident installation that holds up under vibration, saltwater exposure and long-term use. Once in place, routine filter changes are quick and simple, keeping upkeep minimal while protecting some of the most advanced outboards Mercury has ever built.

Why Buy OEM

When you’re running engines like the 450R, 500R or the V12 Verado, you don’t compromise. Aftermarket filters might look similar, but they rarely meet the same fire standards, flow requirements or sensor compatibility Mercury demands. An OEM fuel filter ensures proper fit, correct water-separation performance and long-term reliability — the kind that protects not just your engine, but your entire day on the water. If a fellow boater asked what to trust on a high-horsepower setup, the answer would be simple: go OEM or don’t go at all.

FAQ

Q1: Which engines does the 8M0166540 filter kit fit?

Mercury Racing 450R, 500Rhp and Mercury V12 Verado/SeaPro outboards within the listed serial ranges.

Q2: What makes this OEM kit better than aftermarket versions?

It meets Coast Guard and ABYC standards, integrates with Mercury sensors and provides superior contaminant removal.

Q3: How do I confirm this is the correct kit for my engine?

Match your outboard’s serial number to the ranges listed above or consult your Mercury service manual.

Q4: Is this filter suitable for both freshwater and saltwater boating?

Absolutely — it’s built for harsh offshore conditions and extreme environments.

Q5: Is installation straightforward?

Yes. The kit includes everything needed for a clean, secure installation.