The float in the carburetor regulates the amount of fuel or gasoline which resides in the reservoir. The reservoir of the carburetor is where the fuel is sucked into the intake manifold. A bad or sticking carburetor float causes engine problems. Watch for certain signs and symptoms if you suspect the carburetor float is sticking.
One of the signs that the carburetor float is sticking is when the engine will not idle. The float is not letting enough fuel into the reservoir, allowing for a constant idle of the engine. The carburetor float is stuck in the closed position, and only a small amount of fuel is seeping into the reservoir.
A flooded carburetor is another symptom that the carburetor float is sticking. The float is stuck in the open position, allowing fuel to run freely into the reservoir and then into the intake manifold. Once too much fuel is allowed into the carburetor reservoir, the carburetor floods and cannot be started until all the fuel is expelled from the reservoir.
The engine will begin to stall or hesitate when the carburetor float sticks. This symptom develops under driving conditions when the operator attempts to accelerate. The engine will act as though is it going to die, but catches and begins to accelerate normally. The hesitation of the engine is a similar event.
Another sign or symptom of a sticking carburetor float is when the engine misses out or misfires. One or more cylinders are not getting enough fuel or getting too much fuel when they are being fired by the spark plugs. This happens when the float is stuck, either in the open or closed position. The engine will stall, not idle smoothly or backfire once the carburetor float sticks.