Valve Pin Set Screw OS29116208 for 90RSR-M by O.S. Engine  [OS29116208]

Valve Retention Screw Information

This O.S. Engine component is described as the valve pin set screw for the 90RSR-M reference, intended as a replacement item for valve retention and service tasks on compatible RC engines. Fit this screw when the 90RSR-M parts list or service instructions call for the valve pin set screw.

The set screw secures valve pins so valve timing remains stable after disassembly or rebuild work. In practical workshop use, make sure the valve train is aligned and the threads engage cleanly before tightening, take care to avoid cross-threading, and verify that valves operate freely once the engine is reassembled.

During rebuilds or tuning this small fastener is part of standard valve maintenance procedures. When working on the head or cam assembly, treat the screw as sensitive to torque: start threads by hand, check seating, and re-check clearances following engine run-in.