Polaris TRAIL BOSS 325 2001 Manual page 142

FUEL SYSTEM/CARBURETION
FUEL PUMP
The Trail Boss is equipped with a pressure regulated fuel pump (about 1-3 PSI). The pump is located under the
headlight cover at the front of the machine. Refer to illustration on following page for fuel pump component identifi-
cation.
To test the fuel pump:
1. Turn fuel off.
2. Disconnect impulse line from pump.
3. Connect Mity-Vac¥ (PN 2870975) to the impulse line fitting on the pump.
4. 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 and the pump
diaphragms must be replaced.
FUEL PUMP DISASSEMBLY
1. Refer to illustration on following page.
2. Mark the pump layers to ease assembly.
3. Remove the screws from the pump diaphragm cover. Note the location of the two longer screws.
4. Remove the diaphragm cover gasket, diaphragm, and valve body gasket.
5. 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. CAUTION:
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.
diaphragms and gaskets as a set.
4. Reassemble the pump in the reverse order of
disassembly. Tighten all screws evenly.
4.16
Some carburetor
Replace