ARMY TM 9-2815-256-24
AIR FORCE TO 38G1-96-2
MARINE CORPS TM 2815-24/5
3-27.4.3 Hydraulic Head.
Compressed air used for cleaning can create airborne particles that may enter the eyes and cause
serious injury. Pressure will not exceed 30 psig (207 kPa). Eye protection required.
Five vent wire screw assembly (52, FIGURE 3-54) sizes are available. If specific oil return flow is
not obtained during test, replace screw with appropriate size.
Check vent wire screw assembly (52) for freedom of movement. Flush head and blow out all passages with
clean, dry air. If vent wire is stuck, replace screw assembly with screw of same part number.
Do not touch machine finished surfaces. Damage due to corrosion could occur.
If damage or excessive wear is apparent, head and rotor must be replaced as a matched set. Final
check for excessive wear on rotor should be performed on test stand by checking for minimum
Examine radii contacted by leaf spring and tang slot for excessive wear. Check all slots and charging and
discharge ports for chipping of edges or dirt, and rotor shank for major scratches. Slight erosion on edge of
discharge port is considered normal.
3-27.4.5 Delivery Valve.
Inspect delivery valve retraction cuff for chipping or erosion of edges.
Do not force plungers into their bore and do not handle precision parts of rotor.
While holding rotor under clean oil, insert plungers into their bores facing same direction as they were removed.
With thumb and forefinger over shoe slots, tilt rotor from side to side several times to determine complete
freedom of movement. If new plungers are being installed, interchanging their positions may be necessary as
rotor and plungers become matched parts. If plungers are sticking, but not visibly damaged, clean both
plungers and bore with a soft brush and solvent such as lacquer thinner or acetone.