Genuine Thunder Tiger drive washer set for the PRO-40 and PRO-46 two-stroke aeroplane engines, supplied complete with its split brass collet. The drive washer is the spiral-knurled face that clamps the propeller against the crankshaft and transmits the engine's torque to it, while the tapered collet inside grips the crankshaft as the prop nut tightens — together they're the complete clamping system between engine and propeller.

Replace the set whenever the knurling has polished smooth, the collet or its taper seat is scored from a spun prop, or a crash has left the driver visibly out of true — a bent driver wobbles every prop you fit behind it. Because driver and collet wear as a pair, replacing both together (as supplied here) is the right fix; a fresh driver on a worn collet still slips. While it's off, inspect the crankshaft threads and taper for damage, since a slipping prop often marks the shaft too.

Genuine PRO-series spares are worth securing while they're available: with Thunder Tiger's engine production wound back, factory parts like this are increasingly what keeps these dependable workhorses flying — and the PRO-40/46 earned a big Australian following in trainers and sport models that are still airborne today.

Specifications

Brand: Thunder Tiger
Part number: PN0023
Type: Drive washer with split collet
Materials: Knurled steel driver, brass collet
Suits: Thunder Tiger PRO-40, PRO-46