O.S. Engine OS42525310 S-25 Silencer Gasket for RC Glow Engine Mufflers  [OS42525310]

S-25 Exhaust Seal Details

This S-25 silencer gasket from O.S. Engine is an RC-scale replacement seal intended for mufflers and silencers accepting the S-25 style O-ring. It carries related references F-6020 and FSa-155 and is provided as a single sealing component to re-establish a tight joint and reduce exhaust blow-by.

Fitting involves removing the silencer, inspecting the mating face for carbon build-up or burrs, seating the O-ring into its groove, and refitting while ensuring even compression across the joint. Be careful not to distort the ring during fitment and perform an initial run check to ensure no exhaust leaks are present.

Maintaining a correctly seated silencer gasket helps keep exhaust backpressure stable, which supports a steady idle and predictable throttle response on glow engine models. Replace the O-ring if it shows hardening, cracking, or deformation as part of routine maintenance.