Mercury – 300 Hour Maintenance Kit | FourStroke EFI Service Package | Complete OEM Components | 8M0097857

Overview

Every boater knows that when you hit that 300-hour mark, you’re not just doing another routine service—you’re giving your engine the deep care it needs to carry you confidently into the next season. The Mercury 8M0097857 300 Hour Maintenance Kit brings that sense of reassurance together in one thoughtfully assembled package. Designed specifically for Mercury 1.7L 75–115 horsepower FourStroke EFI outboards, it gives you the exact parts Mercury built your engine around. There’s something grounding about opening a box and knowing everything you need is right there—no guessing, no mismatched parts, just the satisfaction of doing the job right.

Key Features

• Complete 300-hour service kit for Mercury 1.7L FourStroke EFI outboards
• Includes oil filter, fuel filter, gearcase drain seals, four spark plugs, thermostat kit, water impeller kit, alternator belt, and anodes
• High-pleat oil and fuel filters deliver strong, clean filtration for long-term engine health
• Electroplated filter housings resist corrosion in harsh marine environments
• All components engineered to meet Mercury Marine’s exact OEM specifications

Engine & Boat Compatibility

This Mercury Marine part number 8M0097857 fits:

• Mercury 1.7L 75–115 horsepower FourStroke EFI outboards
• Engines with serial numbers 1B366823 through 2B094995
• Commonly used on pontoons, fishing boats, center consoles, and family runabouts

If you depend on one of Mercury’s early FourStroke EFI models, this kit ensures you’ve got everything necessary to perform a complete, factory-correct 300-hour service.

Performance & Practical Benefits

A 300-hour service is the moment you reset your engine’s foundation. Fresh spark plugs wake up smoother ignition. The impeller restores steady, confident cooling. The new alternator belt eliminates the subtle slip or chatter you might’ve been hearing under load. The filters keep oil and fuel clean, helping your engine run tight and controlled across the full throttle range.

What boaters appreciate most is the natural fit and feel of true OEM parts. Everything aligns cleanly. Hardware seats the way it should. The water pump components slide into place without forcing them. Even the anodes feel more solid than the bargain-bin alternatives. When you finish the job, you know your outboard isn’t just serviced—it’s refreshed, protected, and ready for long days on open water.

Why Buy OEM

If you want your engine to last, the smartest move is sticking with Mercury’s own parts. Here’s why seasoned boaters rely on OEM:

• Built for your exact outboard—no guesswork
• Long-term reliability backed by Mercury’s testing and design standards
• High-grade filters and components proven to withstand heat, vibration, and corrosion
• Cost-effective protection by avoiding premature failures caused by off-brand parts
• Everything you need in one complete, organized kit

Ask any veteran at the dock—they’ll tell you the same thing: OEM saves time, money, and frustration.

FAQ

Q1: Which engines does the 8M0097857 kit fit?

It fits Mercury 1.7L 75–115 horsepower FourStroke EFI engines with serial numbers 1B366823 to 2B094995.

Q2: How is this kit better than aftermarket versions?

Every part is OEM, engineered by Mercury to match factory specs and withstand marine conditions.

Q3: How can I confirm this is the correct kit?

Check your outboard’s serial number and confirm it falls within the supported range.

Q4: Is this kit suitable for both saltwater and freshwater boats?

Yes—every component is built for durability in either environment.

Q5: Can most boat owners handle the installation?

Many do. With a service manual and basic tools, this kit is straightforward to install.