Description

Carburettor Float for the SU carburettor float chamber, within the fuel metering circuit of the 3.5L V8 twin-carburettor petrol engine.

The float rides on the fuel standing in the float chamber and acts on the needle valve at the fuel inlet. As the chamber fills, the float lifts and closes the needle against its seat; as fuel is drawn off through the jet, the float drops and the valve reopens. The result is a constant fuel level held at the jet, which is what fixes the mixture strength the carburettor delivers across the engine’s operating range.

A float that has become fuel-logged or distorted no longer closes the needle at the correct height, allowing the level to rise and producing flooding, fuel spillage from the overflow and persistently over-rich running. Float level should be checked and set to specification after fitting.