TM 9-2910-226-34
Table 3-7 ©
Calibration of LDS-465-2
(Code A Pump)
Figure 3-168. Aligning scribe mark on timing device hub
with timing pointer.
b.
Slowly actuate the nozzle tester until a pressure
reading of 400 psig is attained.
NOTE
Do not exceed 425 psig as damage to pre-
formed packings may
result.
c.
The pressure will drop slowly. When pressure
drops to 350 psig, time the rate of pressure drop to 250
psig, If the time of pressure drop from 350 to 250 psig is
less than 30 seconds, leakage is indicated.
NOTE
The time given for test flud at 80
0
F. Test
fluid temperature above 80
0
F. will tend to
reduce time, while test fluid temperatures
below 80
0
F, will tend to increase the time
for the pressure to drop to 250 psig.
Check for visible external leaks at connections, around
the hydraulic head, fuel control unit shaft and plunger
drive gear.
If no visible external leakage is present, the
leakage is internal. Presence of fuel as the fuel control
unit indicates a worn fuel control unit shaft, or a
damaged control unit packing. Install a new control
unit packing (para 3-44) and repeat test. If leakage is
still present, install a new fuel control unit (para 3-44).
Fuel leakage in the area of the plunger drive gear, as
observed through the timing window opening, indicates
a damaged hydraulic head, lower ring packing or a
worn fuel plunger. Install a new hydraulic head lower
ring packing (Para 3-28) and repeat test. If leakage is
still present, install a new hydraulic head assembly
(para 3-40). An external leak at the bottom of the
hydraulic head flange indicates a damaged hydraulic
head upper ring packing. Install a new aulic head upper
ring packing (para 3-28) and repeat test.
d.
Install timing device cover and timing window
cover or fuel shutoff housing.
3-100
Change 2