TM 10-4320-344-24
ERPM in step m refers to engine rpm.
Keep in mind that most test bench
tachometers register pump RPM, which is one half engine speed for four stroke
cycle engines.
m.
Operate pump at 1,000 ERPM wide open throttle
To prevent the possibility of embedding foreign
glasses must be worn when using compressed air.
n.
Using compressed air, completely dry pump.
o .
Check for leaks and correct as required.
(WOT) for 10 minutes.
objects in the eyes, safety
p .
Back out high idle, low idle, and torque screw.
q .
Perform vacuum check as follows:
(1) Close valve in fuel supply line.
(2) Operate pump at 400 ERPM.
Transfer pump must be capable of creating vacuum of at least 18 inches of
mercury.
(3) If pump does not meet minimum specifications, check for air leaks between
pump inlet and shutoff valve.
(4) If no leaks are present, check for damaged or defective transfer pump
components.
r .
Fill graduates to bleed air from test stand and to wet glass.
s .
Direct return oil flow into appropriately calibrated graduate for a given time
and check return oil quantity.
t .
Operate at specified speeds with wide open throttle and observe transfer pump
pressure.
Do not exceed 130 psi (912 kPa) under any circumstances.
Damage to pump may
r e s u l t .
u.
To raise or lower transfer pump pressure, adjust pressure regulating spring
plug as follows:
(1) Remove line to transfer pump inlet connector.
(2) Using 5/32 inch (3.97 mm) hex key wrench, adjust plug.
Do not over-adjust plug.
Damage to plug or pump may result.
(3) Turn plug right to increase pressure.
Turn plug left to decrease pressure.
v .
Check for minimum delivery at cranking speed.
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