Parker P1 Series - Page 53

Parker Hannin Corporation
Hydraulic Pump and
Power Systems Division
Marysville, Ohio USA
Bulletin HY28-2665-02/SVC/EN
Medium Pressure Axial Piston Pumps
P1/PD Maintenance
53
19. Apply light oil lm to control piston and install it in the control guide bore.
NOTE: The 140 size has a lubrication hole in the piston. Conrm that the hole
is facing the port block. The control piston has nonsymmetrical lubrication
grooves. The end with the closest grooves must be installed towards the port
block.
20. Apply light oil lm to the bias piston. Install the bias spring and the bias pis-
ton in the bias piston guide bore.
21. Apply a light layer of petroleum jelly to the back surface of the port plate.
Install the port plate on the port block, lining up the slot on the port plate with
the locating pin.
22. Install the large o-ring in the groove on the pump port block. Install the three
white Teon o-rings in the pressure communication ports on the pump hous
-
ing.
23. Install the cam bearings in the cradle area of the housing. The chamfer on
the back of the bearing must face the outer wall of the housing. Use Loctite
Primer Grade “T” or other suitable primer on screws and mating threads
in housing. Apply Loctite #242 (use sparingly) to screw threads and install
orice screws to hold bearings in place. Torque screws to 3.4 ± 0.25 Nm (33
± 3 in-lb).
24. Place thin lm of clean oil on cam bearing surfaces. Install cam in housing.
The cam must be tilted to permit entry into the housing. (Figure 2) NOTE: The
large pocket on the bottom surface of the cam must be on the same side as
the three pressure communication holes on the main housing. Pump rotation
does not affect the assembly of the cam.
25. Install the drive shaft into the pump housing. Position pump horizontally.
Install the rotating group over the pump shaft. Rotate the barrel to insure that
it is seated against the cam. Insure that the pump shaft is seated properly in
the front bearing.
26. Install bearing spacer as determined from the chart (see step 11.) Install the
rear bearing on the drive shaft.
27. Conrm that compensator rotation, port plate rotation, control and bias pis-
ton location indicate same direction of rotation.
28. Carefully install the assembled port block on the pump housing. Press the
port block to compress the bias spring and install housing bolts. Tighten the
bolts in a cross pattern to insure the port block does not get cocked on the
housing. When port block is seated on the housing, torque bolts in a cross
pattern as specied in chart 4.
29. Install o-ring seals and assembled compensator on side of pump housing.
Pump rotation is indicated by arrow on compensator housing. Torque bolts to
5 ± 0.25 Nm (45 ± 3 in-lb).
Chart 4
Pump
Housing Bolt
Torque
060
135.6 ± 5 Nm
(100 ± 4 ft-lbs)
075
135.6 ± 5 Nm
(100 ± 4 ft-lbs)
100
229 ± 7 Nm
(170 ± 5 ft-lbs)
140
278 ± 7 Nm
(205 ± 5 ft-lbs)
060, 075, 100, 140 Pump Maintenance
PUMP ASSEMBLY PROCEDURE
Continued