Piper ARROW III, Руководство по обслуживанию

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9-24. ADJUSTMENT OF ELECTRIC FUEL PUMP (BENCH TEST).
a. Ascertain that the pump is sufficiently lubricated to prevent damage if run dry for a period greater than
five minutes.
b. Connect the electric leads to a 14-volt dc power source.
c. Using a suitable container with a proper octane fuel, connect a fuel line from a container to the inlet
side of the pump.
d. Connect another line from the outlet side of the pump to a pressure gauge and bypass valve and back
to the container.
e. Run the pump with the bypass valve open until a steady flow of fuel is obtained. Then close the bypass
valve and check the pressure gauge for a proper reading of 26 to 29 psi, no flow. Do not keep the
bypass valve closed for more than one minute during pump operation and adjustment.
f. Loosen the locknut and turn the adjusting screw until there is a reading of 29 psi maximum, no flow,
on the gauge. Repeat steps e and f until the proper pressure is obtained.
g. Disconnect the power source from the pump and lock the adjustment screw with the locknut. Remove
the fuel lines from the pump.
9-25. ADJUSTMENT OF ELECTRIC FUEL PUMP (IN AIRPLANE).
a. With the access panel removed and the fuel selector in the OFF position, remove the fuel line from the
outlet end of the pump.
b. Connect a test line with a bypass valve and pressure gauge to the outlet end of the pump.
c. Place a container below the pump to catch any fuel from the test line during the adjustment of the
pump.
d. Turn the fuel selector on, open the bypass valve on the test line and start the pump.
e. When a steady flow of fuel is obtained, close the bypass valve and check the reading on the pressure
gauge. It should read 26 to 29 psi, no flow. Do not keep bypass valve closed for more than one minute
during pump operation and adjustment.
f. Loosen locknut on adjusting screw and turn screw to obtain the proper pressure of 29 psi maximum,
no flow. Repeat step g and h until adjustment is complete. Lock adjusting screw with locknut.
g. Turn off fuel pump and close fuel selector. Remove the test line from the pump.
h. Reconnect the original fuel line to the pump. Open fuel selector and run the pump to check for any fuel
leaks.
i. Shut off the pump, close the fuel selector and replace and secure the access panel.
9-26. INSTALLATION OF FUEL PUMP.
a. Position the fuel pump inside the cover assembly and secure with cap screws, washers and plate.
b. Connect the fuel lines to the fuel pump.
c. Connect the electrical leads to the pump.
d. Turn the fuel selector on and operate the fuel pump. Check the line fittings for leakage.
e. Install the cowling.
9-27. CLEANING FUEL SYSTEM.
a. To flush the fuel tanks and selector valve, disconnect the fuel line at the injector.
b. Select a fuel tank, turn on the electric fuel pump and flush fuel through the system until it is
determined there is no dirt and foreign matter in the fuel valve or tank. During this operation, agitation
of the fuel within the tank will help pick up and remove any dirt.
c. Repeat this procedure for each tank.
d. When tanks are flushed, clean all filters.
Revised: 2/13/89
2E24
CHEROKEE ARROW III SERVICE MANUAL
FUEL SYSTEM