Mikuni Type Carburetor
All models are equipped with slide type Mikuni carburetors. Refer to Tables 1.22-1.25 for carburetor identification and specifications. The Mikuni carburetor are often found on snowmobiles and motorcycles.
A hand-operated choke lever located on the bowl is used for cold starting. Fuel is supplied by a remote pulse type fuel pump.
The carburetors installed on all models consist of several major systems.
A float and float valve mechanism maintain a constant fuel level in the float bowl. The pilot system supplies fuel at low speeds. The main fuel system supplies fuel at medium and high speeds. Finally, a choke system supplies the rich mixture needed to start a cold engine.
Float Mechanism
To assure a steady supply of fuel, the carburetor is equipped with a float valve through which fuel flows by the pulse operated fuel pump into the float bowl. Inside the bowl is a combined float assembly that moves up and down with the fuel level.
Resting on the float frame is a float needle, which rides inside the float valve.
The float valve regulates fuel flow into the float bowl. The float needle and float valve contact surfaces which are accurately machined to insure correct fuel flow calibration. As the float rises, the float needle rises inside the float valve and blocks it, so that when the fuel has reached the required level in the float bowl, no more fuel can enter.
