O.S. Engine OS28309000 propeller washer GT33 for RC engine crank shaft accessory  [OS28309000]

Propeller washer GT33 overview

This propeller washer is an RC-scale accessory intended to sit between a propeller and its retaining hardware on model engine crank shafts. It is a dedicated GT33-design washer supplied under O.S. Engine's OS28309000 reference and serves a simple mechanical role: to provide a consistent contact surface that helps the propeller seat reliably against the prop hub.

Installation is straightforward and requires no special tools beyond those already used for prop mounting. Slide the washer over the crank shaft or prop adapter, position the propeller, then fit the retaining nut or retainer as your engine's manual specifies. The washer's purpose is to stabilise seating and reduce variations when you tighten the prop mounting hardware.

In tuning and bench work the washer supports repeatable propeller placement, which can make minor adjustments in balance and timing easier to evaluate. It is also useful as a replacement or spare item for routine inspection cycles, allowing quick swaps when performing prop checks or routine maintenance between flights.