The most common reason for a non-spraying accelerator pump nozzle is a clogged nozzle. This can be caused by dirt, debris, or old fuel. To clean a clogged nozzle, remove it from the carburetor and use a small piece of wire to clear out the orifice. Be careful not to damage the nozzle.
Wrong Nozzle Size
Another possibility is that the accelerator pump nozzle is the wrong size for the carburetor. This can cause the fuel to spray in the wrong direction or not spray at all. To check the nozzle size, refer to the carburetor specifications.
Low Fuel Level
If the fuel level in the carburetor is too low, the accelerator pump will not be able to draw fuel up to the nozzle. Check the fuel level and add fuel if necessary.
Weak Accelerator Pump Spring
A weak accelerator pump spring can also prevent the accelerator pump from spraying fuel. The accelerator pump spring is responsible for pushing the accelerator pump diaphragm down, which creates suction that draws fuel up through the nozzle. If the spring is weak, it will not be able to create enough suction to draw fuel up to the nozzle.
Leaking Accelerator Pump Diaphragm
A leaking accelerator pump diaphragm can also prevent the accelerator pump from spraying fuel. The accelerator pump diaphragm is responsible for creating the suction that draws fuel up through the nozzle. If the diaphragm is leaking, it will not be able to create enough suction to draw fuel up to the nozzle.
Bad Accelerator Pump
If all of the above items are checked and the accelerator pump is still not spraying fuel, it is possible that the accelerator pump is bad. The accelerator pump is a mechanical device and can wear out over time. If the accelerator pump is bad, it will need to be replaced.
