For use on:
• Yanmar diesel engine

• Outside diameter: 4"
• Prop shaft diameter: 1"

All transmission couplings require proper fitting & facing to the propeller shaft to ensure concentricity. Specialized machinery and tooling are required to properly install a coupling to a shaft. It is strongly recommended this work be performed by a qualified machine shop or boat yard.

It is also mandatory that the shaft be dimpled to match the coupler set screws prior to use. These dimples prevent the shaft from pulling out of the coupler when the engine is shifted into reverse.