How to Clean the Scum off an Outboard Boat Motor
- 1). Mix a cup of mild liquid dish detergent and a cup of vinegar into a gallon of water. Wash the motor thoroughly with this mix as soon as you can after you take the boat out of the water. A rinse isn't enough to remove scum from the parts of your motor where it has a foothold. Rinse with clear water.
- 2). Pour 1 cup of lime remover into a spray bottle. Add 1 cup of water to the bottle.
- 3). Spray the lime remover mix onto the scum on the motor. Use a soft-bristle brush to scrub the scum away.
- 4). Remove any remaining scum by dipping a plastic scrubbing pad into the lime removal mixture and scrubbing the scum. Remember, though, that vigorous scrubbing with these pads may leave scratches to which scum may adhere in the future.
- 5). If any scum remains, use the blade of a jackknife to mechanically remove the scum. After you finally remove the scum, wash the entire motor with mild soap and water.
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