B
126
Repair and Service Manual
FUEL SYSTEM
Read all of SAFETY and this section before attempting any procedure. Pay particular attention to Notices, Cautions, Warnings and Dangers.
653045
GENERAL
NOTICE: NOTICE: Hardware that is removed must
always be installed in its original position unless
otherwise specified. If torque values are not speci-
fied, refer to the Torque Specifications table in the
“GENERAL INFORMATION AND ROUTINE MAINTE-
NANCE” section.
The fuel system consists of a fuel tank, fuel lines, fuel fil-
ter, fuel pump, carburetor and CARB Canister (Ref. Fig.
To decrease the risk of serious
injury or death resulting from a pos-
sible explosion, do not smoke near
the fuel tank or refuel near open flame or electrical
items which could produce a spark.
Always wear safety glasses
while refueling to prevent possi-
ble eye injury from gasoline or
gasoline vapor.
When refueling, inspect the fuel
cap for leaks or breaks that could result in fuel spill-
age.
Do not handle fuel in an area that is not adequately
ventilated. Do not permit anyone to smoke in an
area where vehicles are being fueled.
The fuel tank is located under the seat (Ref. Fig. 2). Fill
the tank with fresh, clean, automotive grade, unleaded,
87 octane (minimum) gasoline. High altitude or heavy
use/load applications may benefit from higher octane
gasoline.
Fuel Tank
The fuel tank is designed to allow room for fuel expan-
sion. The tank does not require space below the bottom
of the filler neck.
Fig. 2 Fuel Tank
CARBURETOR OPERATION
The carburetor consists of four different systems:
•
Float System
•
Pilot Jet System
•
Main Jet System
•
Choke System
Float System
The float chamber is located on the underside of the car-
buretor. The correct fuel level is maintained by means of
the float and needle valve.
As the fuel flows from the fuel pump, it must pass through
the needle valve and into the float chamber. As the fuel
enters the float chamber, the float starts to rise against
the needle valve. When the buoyancy of the float exceeds
the fuel pressure on the needle valve, the float closes the
needle valve. The float maintains the correct fuel level
within the float chamber and it is not adjustable. As fuel is
consumed from the float chamber, the float drops which
allows the needle valve to admit additional fuel.
Pilot Jet System
The pilot jet system function is to deliver fuel to the engine
during low speed operation. The fuel flow is determined
by the pilot jet size and the setting of the pilot screw.
Main Jet System
The main jet system function is to deliver fuel to the
engine during acceleration and heavy load conditions.
Fuel flow is determined by the main jet size. Air is mixed
with fuel that passes through the bleed opening in the
main nozzle. This mixture passes into the carburetor ven-
turi as atomized air/fuel is mixed with intake air and deliv-
ered to the engine.
Choke System
The choke functions to make initial starting of the engine
easier in cold weather conditions. The choke plate
restricts the air flow into the carburetor which enriches the
air/fuel ratio.
Carburetor Service
Be sure that the ignition system is functioning correctly
before determining that servicing the carburetor is
required. Refer to the ELECTRICAL section for ignition
system information.
Choke Operation
Pull the choke knob (10) out to operate the choke (Ref.
Fig. 3). Check that the cable operates smoothly and that
the cable returns when the knob is released. The motion
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