FS-series FS-95V Valve OS40960100 Replacement for O.S. Engine  [OS40960100]

FS-95V Service Valve for FS Engines

Designated OS40960100 under the O.S. Engine parts list, this FS-95V valve serves as a direct replacement for FS-series glow engines used in RC model applications. The assembly features a precision ground steel stem intended to match original service tolerances.

Use is limited to FS-series O.S. glow engines that require the FS-95V valve; verify the part number with your engine documentation because the listing does not specify every compatible engine variant beyond the FS-series label.

Installation guidance: strip the cylinder head and valve train following the manufacturer's service instructions, fit the new valve, and check for correct valve-to-seat engagement and stem clearance. Reassemble and run the engine under controlled conditions to confirm sealing and idle stability. Avoid forcing parts during reassembly to prevent damage.

Role in tuning and upkeep: although the valve itself does not modify carburetor settings or ignition timing, maintaining a proper valve seal preserves compression and steady idle performance, which makes subsequent tuning more predictable. Regular checks for surface wear and stem alignment will reduce the risk of running issues.