Polaris Outlaw 500, Service Manual

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4.13
FUEL SYSTEM / CARBURETION
4
2. Open bowl drain screw by turning counterclockwise
approximately two turns. Start and run engine for 3 to 5
seconds to allow fuel level to stabilize in the line. If level
is out of specification, remove carburetor and inspect inlet
needle and seat, float height, passages, etc.
NOTE: If a line was removed to perform this
procedure, it must be replaced.
Fuel Pump
This 500cc is equipped with a pressure regulated fuel pump
(1–3 PSI). The pump is located in the front fender cavity of the
machine.
To test the fuel pump:
1. Turn fuel off.
2. Remove the front cab to access the fuel pump if needed.
3. Disconnect impulse line from pump.
4. Connect Mity–Vac™ ( PN 2870975 ) to the impulse line
fitting on the pump.
5. Apply 5 inches (Hg) vacuum to the pump fitting. The
diaphragm should hold vacuum indefinitely.
If fuel is present in the impulse line or vacuum chamber of the
pump, the diaphragm is ruptured. The pump diaphragms must
be replaced.
Fuel Pump Disassembly
1. Remove the screws from the pump diaphragm cover. Note
the location of the two longer screws.
2. Remove the diaphragm cover gasket, diaphragm, and valve
body gasket.
3.
Remove the outlet check valve cover, diaphragm, and
gasket.
Fuel Pump Inspection / Assembly
1. Inspect inlet and outlet check valves for cracks, warpage or
damage. Inspect the diaphragms for cracks, holes or
swelling.
2. To clean the valves or pump body, remove the set screw and
washer. Remove the valve and wash with soap and water.
Carburetor cleaner may be used to clean the pump body
when the check valves are removed.
IMPORTANT: Some carburetor cleaners are very
caustic and should not be used to clean the non–
metal parts of the fuel pump.
3. Check the sealing surfaces of the pump body and covers.
Carefully remove all traces of old gasket and check the
surfaces for damage. Replace diaphragms and gaskets as a
set.
4.
Reassemble the pump in the reverse order of disassembly.
Tighten all screws evenly.
TROUBLESHOOTING
Fuel Starvation / Lean Mixture
Symptoms: Hard start or no start, bog, backfire, popping
through intake / exhaust, hesitation, detonation, low power,
spark plug erosion, engine runs hot, surging, high idle, idle
speed erratic.
• No fuel in tank
• Restricted tank vent, or routed improperly
• Fuel lines or fuel valve restricted
• Fuel filter plugged
• Carburetor vent line(s) restricted
• Plugged or restricted inlet needle and seat screen or
inlet passage
• Clogged jets or passages
• Float stuck, holding inlet needle closed or inlet needle
stuck
• Float level too low
• Fuel pump inoperative
• Air leak at impulse line
• Restricted impulse line (kinked, pinched)
• Intake air leak (throttle shaft, intake ducts, airbox or air
cleaner cover)
Impulse Line
Fuel Pump