Mercury – Water Pump Kit | Cooling System | Marine Composite & Rubber | 8M0137849

Overview

There’s a certain rhythm to a good day on the water—smooth throttle response, a steady hum from the outboard, and the comforting feeling that everything beneath your feet is running exactly as it should. A dependable cooling system is a huge part of that peace of mind. The Mercury 8M0137849 Water Pump Kit is one of those quiet heroes you rarely think about until you need it. Once installed, you can feel the difference in the way your engine settles into its work, staying cool and confident whether you’re creeping through a no-wake zone at dawn or running wide across an open stretch of lake.

Key Features

• Maintains proper engine cooling for long-term performance
• Heavy-duty faceplate and reinforced housing for abrasive water conditions
• Engineered with marine-grade rubber and durable composite components
• Designed to meet Mercury Marine original equipment standards
• Fits Mercury 15 and 20 horsepower EFI FourStroke outboards
• Reliable, factory-quality construction for long service life

Engine & Boat Compatibility

• Mercury EFI FourStroke 15 horsepower outboards (serial number 0R833820 and above)
• Mercury EFI FourStroke 20 horsepower outboards (serial number 0R833820 and above)
• Commonly used on jon boats, small fishing rigs, tenders, inflatables, and lightweight utility skiffs
• Ideal for boaters running in sandy, shallow, or debris-prone waterways

Performance & Practical Benefits

A water pump might seem like a simple piece of hardware, but anyone who’s had one fail knows exactly how essential it is. With this kit installed, the cooling system delivers steady flow and consistent pressure, keeping small EFI engines running cool even when you spend long days hopping spot to spot. The heavy-duty faceplate and upgraded housing help the pump hold up in gritty or abrasive water—conditions that tend to wear lesser pumps down fast.

You’ll notice the motor feels smoother and more predictable at idle, and it maintains temperature more confidently during long runs. When the pump is doing its job, you’ll feel that subtle reassurance every time the telltale streams out clean and strong. Maintenance stays simple, too, because Mercury builds the kit for easy replacement with everyday tools and clear fitment precision.

Why Buy OEM

When you’re dealing with a cooling system, shortcuts never pay off. Mercury’s OEM water pump kits aren’t just compatible—they’re engineered for the exact clearances, flow rates, and materials your engine needs. Aftermarket versions may look similar but rarely match the cooling performance or durability required for reliable operation. Choosing OEM means you’re choosing fewer surprises, fewer breakdowns, and cooling performance that’s been tested in the same demanding environments you run in. It’s one of those small decisions that keeps your boat starting, running, and coming home without drama.

FAQ

Q1: Which Mercury engines does the 8M0137849 Water Pump Kit fit?

It fits Mercury 15 and 20 horsepower EFI FourStroke outboards with serial numbers 0R833820 and above.

Q2: What makes this kit better than aftermarket options?

OEM parts are built to Mercury’s exact specifications, offering the precise flow and durability your engine was designed for.

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

Match your serial number and engine model, or reference your owner’s manual for final verification.

Q4: Can the water pump kit be used in both saltwater and freshwater?

Yes—its reinforced housing is designed to withstand abrasion and corrosion in either environment.

Q5: Is installation easy for most boat owners?

Most DIY-minded owners can install it with basic tools, making it a straightforward maintenance task.