1968 Mercury 3.9HP Vintage Outboard Carburetor and Fuel Pump Rebuild

Maintaining older Mercury outboards is very doable considering the amazing availability of replacement parts like carburetor valves, gaskets, floats, and fuel pump diaphragms.

This video covers the steps for removing and rebuilding the carburetor and fuel pump for a 1968 Mercury 3.9HP outboard motor. The same procedure applies to other sizes and model years.

An ultrasonic cleaner is used in this video to clean the carburetor components. The cleaner bath is 3 parts water 1 part Pinesol. After cycling through the cleaner for about 2 hours, the cleaned parts are blown dry with compressed air before reassembly. If an ultrasonic cleaner isn’t available, parts can be cleaned with carb cleaner as an alternative.