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

Valve Pin Set Screw Details

This O.S. Engine part is supplied as the valve pin set screw for the 90RSR-M designation, offered as a small replacement component for RC engine valve retention and routine service tasks. Use this item when replacing or checking the valve mechanism on engines that list 90RSR-M in their service documentation.

Functionally, the set screw secures valve pins and helps preserve valve timing integrity after disassembly or rebuilds. In workshop practice, confirm valve train alignment and proper thread engagement before final tightening, avoid cross-threading, and verify free valve movement after reassembly.

For tuning and rebuild cycles, this screw is a compact but necessary element in valve maintenance. When servicing the cylinder head or cam assembly, treat the screw as torque-sensitive: start threads by hand, confirm seating, and recheck clearances once the engine has been reassembled and run-in procedures completed.