TM 9-4940-549-14&P
(b) Set counter and tachometer switches to clockwise position.
NOTE
Pump runs at half the engine speed.
(c) Start the test stand at lowest speed and check for clock-
wise rotation. Move throttle to full-load position. When
transfer pump picks up suction, allow fuel to bleed for
several seconds from loosened connector screws and injec-
tion line nuts, then tighten securely.
(d) Operate pump at 500 rpm for 10 minutes. Dry off completely
with compressed air.
DELIVERY
PRESSURE
MAX VAR
BETWEEN
PSIG
PUMP
RPM
(mm3/stroke)
CYLINDERS
70-75
900
56-59
3
750
55-58
4
15-20
927 (high idle)
Observe for leaks and correct as necessary.
Back out high idle stop screws.
NOTE
The inlet to the fuel transfer pump
should never be pressurized during
bench testing.
(e) Close valve in supply line-transfer pump must pull at least 18
inches of mercury at 200 rpm. If it does not, check for air
leaks on suction side or malfunction of end plate and transfer
pump parts.
(f) Fill graduates to bleed air from test stand and to wet glass.
(g) Observe return oil. Return should be at rate of 100-450 cc/minute
at 35 psig transfer pump pressure.
Under no circumstances should 130 psig
be be exceeded, as the pump will be
damaged.
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