Flushmaster Outboard Engine Flush Port Quick Connect for Mercury

SEAMULE Flushmaster Outboard Engine Flush Port Quick Connect for Mercury Outboards – Permanent OEM Replacement

SM-FMQCM

• PERMANENT OEM UPGRADE: Directly replaces the factory Mercury flush port plug with a quick-connect fitting, eliminating the need to unscrew and hand-thread the OEM plug every time you flush your engine.
• MARINE-GRADE DURABILITY: Built from corrosion- and UV-resistant materials engineered to withstand constant exposure to saltwater, sun, and engine bay heat without cracking, fading, or degrading over time.
• LEAK-FREE DOUBLE O-RING SEAL: A dual O-ring design creates a tight, consistent seal at every connection, preventing drips, spray-back, and water intrusion during flushing.
• SECURED LOCKING CAP: A quarter-turn locking cap keeps the port sealed and protected against accidental disconnection, water intrusion, and debris while underway or in storage.
• FITS 75HP–500HP MERCURY ENGINES: Compatible with Mercury FourStroke, Racing, Pro XS, and Verado outboards, including V8 and V10 platforms.

About This Item

The SEAMULE Flushmaster Flush Port Quick Connect takes the hassle out of one of the most repetitive maintenance tasks in boating: flushing your outboard. Instead of wrestling with a stiff OEM garden-hose plug every time you flush your engine after a day on the water, the Flushmaster installs once and gives you a permanent quick-connect fitting built directly into your engine cowling. Twist off the cap, snap on your hose, flush, disconnect, and twist the cap back on — the whole process takes seconds instead of minutes.

Engineered specifically for Mercury outboards, the Flushmaster is manufactured from marine-grade, UV-stabilized materials designed to hold up under constant sun exposure, saltwater spray, and the heat inside an engine cowling. A double O-ring seal design ensures a leak-free connection every time, while the secured locking cap adds an extra layer of protection against accidental disconnects or water intrusion when the flush port isn't in use.

Whether you're a weekend angler flushing after every trip or run a charter fleet flushing engines daily, the Flushmaster is designed to save time, reduce wear on your OEM components, and make proper engine maintenance something you'll actually keep up with.

Key Features

• Hassle-Free Flushing: No more fighting with the OEM flush plug. The Flushmaster permanently replaces it with a fitting designed for repeated, everyday use.
• Faster Turnaround: Cuts flushing time down to a simple twist-connect-flush-disconnect-twist routine — ideal for anyone flushing engines frequently.
• Built to Last: Rigorously tested marine-grade construction resists UV degradation, corrosion, and the wear of daily marine use.
• Secure by Design: Locking cap mechanism protects the connection point when the flush port isn't actively in use.
• Patented Design: A patented quick-connect system engineered specifically for Mercury outboard flush ports.

What's Included

• (1) Mercury Male Quick Connect fitting
• (1) Female Hose Quick Connect (Blue)
• (1) 90-Degree Elbow (for kink-free hose routing inside the cowling, if needed)
• (1) Installation Wrench
• (1) Stainless Steel Hose Clamp

Compatibility:

Mercury FourStroke, Racing, Pro XS, and Verado outboard engines, 75HP–500HP, including V8 and V10 models.

Installation Overview

1. Remove the OEM Mercury flush port plug and unscrew it from the 3/4" female hose outlet.
2. Remove the lanyard from the engine hose.
3. Thread the new SEAMULE Flushmaster Flush Port Quick Connect into the flush port.
4. Reinstall the Flushmaster into the engine cowling and turn 1/4" clockwise to lock into place.

Installation Tip: Remove the cowling and check the flush hose for kinks. If a kink is present, replace the Mercury 3/4" female hose outlet with the included 90-degree elbow, orienting it inside the cowling to route the hose kink-free. Lubricating the barb fitting or lightly warming the hose with a heat gun can make the elbow easier to install.