Quicksilver – Fuel Pressure Regulator | MerCruiser MPI Series | Precision Fuel Control | 861126A1

Overview

Every boater knows the feeling of a perfectly tuned engine — that crisp throttle response, that steady push as the boat climbs onto plane. When the fuel system is balanced, everything feels smoother. This Quicksilver fuel pressure regulator is one of those behind-the-scenes parts that quietly keeps the engine behaving its best. It’s the kind of component you trust without thinking about it, because you know it’s controlling the heartbeat of the fuel system with steady, predictable accuracy.

Key Features

• Fuel pressure regulator for select MerCruiser MPI engines
• Mounts directly on the fuel cooler
• Designed to maintain consistent fuel pressure under load
• Built to Mercury Marine OEM specifications
• Quicksilver part number 861126A1

Engine & Boat Compatibility

• Fits MerCruiser 4.3L, 5.0L, 5.7L, 6.2L MPI engines
• Also fits 7.4L MPI (L29), 454 Magnum MPI, 496 Magnum, 500 EFI, and 8.1S and HO platforms
• Common across cruisers, large bowriders, sport cuddy boats, and performance hulls
• Suitable for both freshwater and saltwater boats

Performance & Practical Benefits

A good fuel pressure regulator doesn’t call attention to itself — it simply holds pressure where it needs to be so the injectors deliver the right amount of fuel every time. With this OEM part, you’ll feel smoother acceleration, steadier idle, and cleaner top-end performance.

Under load, the regulator keeps fuel delivery tight and predictable, preventing surging or hesitation. That’s especially important for heavier boats or engines running hard in chop. The construction is built to handle the constant heat of the fuel cooler while resisting corrosion from the marine environment.

Installation is straightforward for anyone comfortable working with MPI systems. Once installed, the regulator settles in with that solid OEM fitment that inspires confidence every time you turn the key.

Why Buy OEM

Fuel components aren’t the place to experiment. Aftermarket regulators often drift out of specification, struggle with heat, or fail prematurely. A genuine Mercury Marine part keeps your engine running the way its engineers intended, protecting both performance and longevity.

If you want your MPI engine to stay healthy — and avoid costly troubleshooting — OEM is the only smart choice.

FAQ

Q1: Which engines does this regulator fit?

It fits a wide range of MerCruiser MPI engines from 4.3L to 8.1L, including performance variants.

Q2: What makes it better than aftermarket versions?

Its pressure control is more stable, and the construction handles marine heat and vibration far better.

Q3: How do I confirm it’s the right replacement?

Check your service manual. If it lists part number 861126A1, this is your match.

Q4: Can it be used in freshwater and saltwater?

Yes — it’s engineered for both environments.

Q5: Is installation straightforward?

For most boaters familiar with MPI systems, yes. It mounts directly to the fuel cooler.