O.S. Engine OS22826133 Replacement O-ring (Exhaust Adaptor No.4) for 21RX, 21RG  [OS22826133]

O-ring for Exhaust Adaptor No.4 compatible with 21RX and 21RG

This compact O-ring is a dedicated replacement seal for Exhaust Adaptor No.4 when used on 21RX and 21RG model engines. It seals the joint between the adaptor and the exhaust output to prevent leaks that could alter exhaust behaviour.

The part is limited to the adaptor designation shown, so confirm the adaptor is No.4 and the engine model is 21RX or 21RG prior to installation. It is supplied as a single service item and is intended for routine maintenance rather than performance modification.

Maintenance tips: inspect mating surfaces for debris or old sealant, position the O-ring evenly into the groove, and avoid pinching or folding the seal when assembling. Replace on signs of cuts, flattening, or loss of flexibility to maintain consistent exhaust performance.