GT55 Carburettor Seal OS29781500 by O.S. Engine  [OS29781500]

What this gasket does and where it fits

The OS29781500 GT55 gasket is a purpose-made replacement seal for model carburettors, designed to close mating surfaces and stop ingress or loss of air and fuel that upset mixture balance and idle smoothness.

Its primary use is maintenance and rebuild work on glow/nitro engine carburettors fitted to model vehicles. As a small service item, it helps reinstate correct sealing after cleaning, needle changes, or minor tuning work. Consider it a consumable part during routine carb service cycles.

Installation notes: extract the carburettor from the chassis, disassemble only to the extent needed to access the contact surfaces, clean all mating faces, replace the old gasket with the OS29781500 unit, and reassemble following original alignment and torque guidelines. Confirm idle and throttle response on a bench test before reinstalling in the model.

Durability and tuning: a tight seal reduces unmetered air that can mask needle settings or cause intermittent running. If you see lean surges or unstable idle after a rebuild, confirm the gasket sits flush and check surrounding seals and throttle components for additional air paths.