MOST COMMON CAUSES

Check ball not sealing

• Is the spring and T in place above the check ball?

Watch a video about how to test the accelerator pump circuit

https://youtu.be/bb_m4c3xS7A

Float bowl not vented. Be sure any vent isn't plugged with something.

• Float bowl not vented. Be sure any vent isn't plugged with something.

Non Vented Gas Cap

• This creates a vacuum in the tank. This will usually cause a whooshing sound when removing the gas cap

OTHER POSSIBLE CAUSES

1. Float Level Set Too High

• If the float level inside the carburetor is set too high, it can cause an excess of fuel in the float bowl, leading to fuel overflowing through the main discharge nozzle even at idle.

2. Stuck or Worn Needle and Seat

• The needle and seat control the flow of fuel into the float bowl. If the needle is stuck open or the seat is worn out, it can cause fuel to continuously flow into the bowl, leading to leakage from the main discharge.

3. Leaking Float

• A float that has developed a leak or has become saturated with fuel will not rise properly to shut off the fuel flow, resulting in an overfilled bowl and fuel leaking from the main discharge at idle.

4. Excessive Fuel Pressure

• If the fuel pump is delivering fuel at too high a pressure, the carburetor may be overwhelmed, leading to excessive fuel entering the float bowl and leaking through the main discharge.

5. Dirty or Clogged Carburetor Passages

• Dirt or debris in the carburetor can block fuel passages, causing improper fuel flow and leading to leakage from the main discharge at idle.