TM 5-3895-383-24
5.
Look at the gauge and depress vibratory on/off control
(3) to the ON position in order to start the vibratory
system.
NOTE:
The force that is needed to overcome the inertia
of the weights causes the pressure in the
vibration system to momentarily reach the low
amplitude relief valve setting. Look at the gauge
and turn on the vibration system. The highest
reading on the gauge is the low amplitude relief
valve setting.
6.
The low amplitude relief valve setting should be 35000 ±
3000 kPa (5076 ±435 psi).
Illustration 53
Vibratory Pump
(9) Low amplitude relief valve.
7. If the low amplitude relief valve setting is not correct, low
amplitude relief valve (9) must be adjusted.
Illustration 54
Relief Valve Cartridge
(5) Spindle. (6) Collar. (7) Lock screw.
8.
Adjust low amplitude relief valve (9) in the following
steps:
a.
Stop the engine.
b.
Remove the cap of high amplitude relief valve (4).
c.
Remove the high pressure relief valve cartridge.
Install the cap of high pressure relief valve (4). This
will prevent oil leakage while adjustments are made to
the cartridge and the spring.
d.
Hold the high pressure relief valve cartridge in a
bench vise. Secure the high pressure relief valve
cartridge by clamping on collar (6).
e.
Loosen lock screw (7) with a 3 mm Allen wrench.
f.
Use a 5 mm wrench and adjust the pressure by
turning spindle (5). Turn the spindle clockwise in
order to increase the pressure. Turn the spindle
counterclockwise in order to decrease the pressure.
One full rotation of spindle (5) equals 4400 kPa (638
psi).
g.
Tighten lock screw (7).
h.
Remove the high pressure relief valve from the vise.
i.
Reinstall the high pressure relief valve cartridge.
Install the cap of high pressure relief valve (4) and
torque to specifications.
9.
Repeat Step 5.
10.
Stop the engine.
NOTE:
After five minutes of operation, when the drum is
on tires, the vibratory operating pressure should
decrease to a maximum of 10340 kPa (1500 psi).
If continued high pressure is observed, a problem
may exist with the vibratory drive mechanism.
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