S-36 and 75AX Cover Plate O-Ring OS27414020 - O.S. Engine  [OS27414020]

Engine Cover Plate Seal O-Ring

The O.S. Engine OS27414020 O-ring is supplied as a cover plate gasket for S-36 and 75AX style crankcases, providing a simple replacement option to maintain internal sealing. It helps preserve the intended environment inside the engine during normal model operation.

Fitment is straightforward: remove the cover plate, thoroughly clean the mating faces of any old gasket material and oil, lay the O-ring into the groove, and refit the plate following the manufacturer's torque guidance for case fasteners. Watch for trapped debris or sharp edges that could nick the seal during installation.

When performing tuning or maintenance, ensure the cover plate O-ring is correctly seated to support reliable compression and reduce air leaks that can compromise idle and throttle control. Replace the seal whenever the cover is removed for service or if the O-ring shows cracking, hardening, or other damage.