Inspection of Sub-Assemblies.

*TM 9-2815-213-34

nector (fig. 3-83), to 1/4-inch flare connector on pump

(7) Turn range crank to "LOW RANGE" (fig. 3-80).

inlet adapter assembly.

(8) Start stand and pump operation by depressing

start switch. Depress and release switch until pump

NOTE

operation is between 400-450 rpm as observed on stand

If during operation of the stand oil is sucked

"TACHOMETER" (fig. 3-80).

into vacuum gage no. 1 (fig. 3-80) it will be

necessary to use a supplementary vacuum

gage (vacuum gage no. 2, fig. 3-80).

NOTE

Disconnect hose from stand supercharger inlet

Check rotameter for presence of air in fuel

connector (fig. 3-83) to pump inlet adapter.

flow. If air bubbles are present, work pump

Connect flexible hose from supplementary

throttle from full open to idle, several times, to

vacuum gage no. 2 to pump inlet adapter (5,

relieve any entrapped air in pump.

fig. 3-79).

(9) Turn on "AUX MOTOR" switch for one minute, to

(9) Install pump discharge fitting assembly (4, fig. 3-79)

eliminate any air entrapped in test stand (fig. 3-80).

in pump fuel shutoff solenoid valve (fig. 3-83).

(10)Adjust "FUEL REGULATOR" to a maximum of

(10)Install flexible hose (10, fig. 3-79) from stand

20 psi as observed on "FUEL PRESSURE" gage (fig. 3-

"PRESSURE GAGE" outlet to pump discharge fitting (fig.

80).

383).

(11)Shut-off "AUX MOTOR" switch.

(11)Install flexible hose (9, fig. 3-79) from stand

"FUEL INPUT" connection to pump discharge fitting (fig.

NOTE

3-83)

If air bubbling persists check all lines for

(12)Install /2-inch ID flexible hose (8, fig. 379) from

leakage. If no leaks are uncovered, or, if fuel

stand "FUEL OUTLET" connector to stand "FUEL

pump fails to pick-up fluid the pump must be

RETURN" connector (fig. 3-83).

disassembled and repaired or replaced.

(13)Install flexible hose (6, fig. 3-79) to no. 1

Proceed with the following steps only if pump

accumulator can (fig. 338), from stand "LEAK TEST"

is operating satisfactorily.

connector.

(14)Turn on fuel heat switch (fig. 3-80), observe that

(12)Increase pump speed to 2100 rpm.

temperature on "FUEL TEMPERATURE" gage is

(13)Set pump throttle to wide open position.

between 80 to 100 degrees for testing.

(14)Set "SUCTION VALVE," "BYPASS VALVE" and

d. Gear Pump Test.

"FLOW CONTROL" to fully open position.

CAUTION

NOTE

Never operate fuel pump until check valve has

Indicated flow on the rotameter should be not

been checked for restrictions.

less than 850 pounds per hour (pph).

(1) Set stand motor switch (fig. 3-80) to "FORWARD."

e. Inspection of Sub-Assemblies.

This corresponds to code designation on pump name

(1) Fuel Shut-Off Solenoid Valve Assembly.

plate. "L" for left-hand (fig. 3-84), as viewed from rear of

(a) Visually inspect shut-off valve and valve seat for

pump.

wear and corrosion. Valve seat must be 0.015 inch

(2) Open stand "BYPASS VALVE," "SUCTION

minimum width.

VALVE" and "FLOW CONTROL VALVE." Back seat all

(b) Check oil assembly with ohm-meter. Replace

other valves to prevent leakage (fig. 3-80).

coil if resistance is below 30 +3 ohms.

(3) Open pump solenoid manual overide knob (fig.

(2) Fuel Pump Damper Assembly. Inspect body,

3-73) by turning fully clockwise.

plate, and diaphragm for excessive wear.

(4) Install throttle spring (fig. 3-82) to hold throttle in

(3) Mainshaft Cover and Governor Assembly.

wide open position.

(a) Perform general inspection in accordance with

(5) Set stand 4-way valve to "ROTAMETER"

paragraph 2-6.

position (fig. 3-80).

(b) Place one leg of depth gage base of pedestal

(6) Set stand power switch to "ON" position.

across the carrier walls and measure down to the front

cover gasket surface (no

3-41