O.S. Engine FS-200S Crank Shaft Mating Washer OS44508000  [OS44508000]

FS-200S crankshaft mating washer

This washer is specified for the FS-200S engine family and is offered as O.S. Engine model OS44508000. It fits on the crankshaft end to locate the drive coupling and maintain the correct axial clearance required for reliable operation.

Fitting is intended for hobby workshops: slide the washer onto the crank flange until it seats against the crankcase face or spacer, confirm the coupling runs true, then measure endplay with a feeler or dial gauge. If endplay is outside acceptable limits, inspect the mating surfaces and any shims before changing washer thickness.

In service and tuning the washer stabilises the drive interface and limits axial movement that can compromise gear engagement or coupling alignment. Regular checks for wear or distortion are recommended during rebuilds or fault diagnosis.