8-9.9hp FourStroke Command Thrust 300 Hour Maintenance Kit

Mercury Marine 8-9.9hp FourStroke Command Thrust 300 Hour Maintenance Kit

The Mercury Precision Parts 8M0120867 300-Hour Maintenance Kit delivers every critical service item needed to perform a complete 300-hour interval service on Mercury 8hp and 9.9hp FourStroke Command Thrust outboards in a single, ready-to-use package. Designed specifically for engines with the Command Thrust (Bigfoot) gearcase and serial numbers 0R042475 through 1R279944, this kit eliminates the need to source individual components and helps ensure every replaced part meets Mercury Marine's stringent OEM standards.

Compatible with both carbureted and EFI models in the 8hp and 9.9hp FourStroke Command Thrust lineup, this kit is a practical choice for owners of jon boats, dinghies, sailboat auxiliary setups, small fishing rigs, and tender craft who want to protect their investment and maintain peak engine performance. Periodic maintenance performed at the recommended 300-hour interval helps keep the engine running longer and stronger while preserving resale value.

All included components are engineered to Mercury Marine's original factory specifications for guaranteed fit and function. The new water pump impeller restores reliable cooling flow, fresh spark plugs promote quick and even starting, updated seals protect against fluid leaks in the gearcase and oil drain, and the replacement thermostat and gaskets ensure proper operating temperature is maintained. The anode helps guard against corrosion in both freshwater and saltwater environments. Service is straightforward using common shop tools; refer to the engine owner's manual for the recommended procedure.

Key Features

• Complete selection of all required 300-hour service replacement items in one box — no need to order separate parts
• Includes in-line fuel filter, oil drain seal, two gear case drain seals, thermostat, thermostat gaskets, two spark plugs, water pump impeller kit, and lower unit anode
• Compatible with Mercury 8hp and 9.9hp FourStroke Command Thrust (Bigfoot) outboards — carbureted and EFI models
• Fits engines with serial numbers 0R042475 through 1R279944
• Genuine Mercury Marine OEM components manufactured to stringent original equipment manufacturer specifications
• Corrosion-resistant components suitable for freshwater and saltwater use
• Serviceable with common shop tools following the owner's manual
• Mercury 4-stroke oil and recommended gear lube sold separately