O.S. Engine OS27981910 Carburettor Needle Set 20M,40E,60B,60G,60H,60L  [OS27981910]

Carburettor needle set for RC engines

This listing covers the O.S. Engine needle codes 20M, 40E, 60B, 60G, 60H and 60L intended as replacement needles for carburettor needle valves on RC glow engines. The set names indicate the identification codes used to match needle profiles during service or overhaul.

Use these needles to restore a worn needle valve or to change the needle profile when adjusting fuel mixture. Installation is a basic carburettor service task: remove the carburettor top, extract the existing needle assembly, inspect the seat and needle tip for wear or debris, and replace with the matching code. Reassemble carefully and verify there are no leaks.

After swapping needles, perform stepwise tuning on the bench and then an on-track test run. Small changes in needle profile affect idle, midrange and throttle response; start with conservative adjustments, monitor engine temperature, and fine-tune mixture and idle screw settings to achieve stable running.