TM 5-4310-393-14
d.
Check the operation of the oil pump It is working properly if no bubbles are visible in the oil pressure regulating
valve sight glass (See figure 3-6, item 3)
e. Vent the pump if bubbles are visible, (paragraph 3-5.4)
3-5.4.
Venting the Compressor Oil Pump.
If bubbles are visible in the oil pressure regulating valve
sight glass, especially after maintenance or repair work,
venting the oil pump will be necessary. Refer to Figure
3-5 and proceed as follows:
a.
With the compressor shut off, and the crankcase
vented, slowly loosen the tube nut (2) Turn the
compressor by hand until bubble-free oil emerges from
the fitting This should only take a few seconds.
b.
Tighten the tube nut (2)
3-5.5. Compressor Oil Pressure Regulator.
a.
Remove cap nut (Figure 3-6, Item 1) to expose
setscrew (2).
b.
Remove the tube plug (4)
c.
Connect a calibrated oil pressure gauge, 0-1500
psi, to the oil pressure regulator test connector (4) to
read oil pressure
d.
Start compressor.
FIGURE 3-5. VENTING THE OIL PUMP
FIGURE 3-6. COMPRESSOR OIL PRESSURE
REGULATOR
e.
Using a screwdriver, turn setscrew (2) in oil pressure regulator (5) to adjust oil pressure
f.
Turn the setscrew clockwise to increase pressure, counterclockwise to decrease pressure.
g.
Oil pressure should be 850 psi +/- 50 psi
h.
If bubbles are observed in the regulator site glass (3) on the oil pressure regulator, it is necessary to vent the
pump, refer to paragraph 3-5.4.
3-5
