YAMAHA DRAIN SCREW 64D-14394-00

Function and technical context

This drain screw is part of the water evacuation system of the Yamaha outboard motor, allowing the controlled expulsion of liquids accumulated in the internal cavities of the block. It is installed in strategic points of the crankcase or engine body where cooling or condensation water is concentrated, avoiding the retention of moisture that could cause internal corrosion and oxidation of critical components. Its correct operation is essential to maintain the structural integrity of the engine and prevent the accumulation of fresh or salt water in areas where it should not remain.

When to replace this part?

Drain screws should be inspected regularly during each seasonal maintenance, especially after sailing in salt water, as they can corrode, seize or develop microcracks that compromise their watertightness. If you notice water leaking around the drain point, difficulty opening it, or signs of advanced rust, it's time to replace it immediately. Preventatively replacing this component before it completely fails prevents further damage to the engine block and ensures reliable drainage throughout the boating season.

Equivalent manufacturer part numbers