Komatsu 830E-AC Shop Manual page 722

Rotating Group
16. Mating surfaces should be greased. Place cylin-
der assembly on clean table with the valve plate
side down.
17. During disassembly, shoe retainer springs were
referenced to individual bores. Assemble rotat-
ing group by inserting shoe retainer springs (28,
Figure 5-25) into the same spring bores located
in cylinder barrel (10) that they came from.
18. Slide fulcrum ball (12) over the nose of the cylin-
der barrel (10).
19. Place shoe retainer (27) over fulcrum ball and
align holes in retainer with corresponding holes
(marked during disassembly) in the cylinder
barrel. Once aligned, insert piston/shoe assem-
blies (13) into corresponding (marked during
disassembly) holes completing the rotating
group.
The assembled rotating group weighs approxi-
mately 14 kgs (30 lbs). Assistance from others
and proper use of proper lifting techniques is
strongly recommended to prevent personal
injury.
20. The rotating group can now be carefully
installed over the end of the driveshaft and into
the pump housing (20, Figure 5-24).
21. When installing the rotating group, support the
weight of the cylinder barrel (10, Figure 5-25) as
cylinder spline is passed over the end of drive-
shaft to avoid scratching or damage.
22. Push cylinder barrel forward until the cylinder
spline reaches the driveshaft spline. Rotate the
cylinder slightly to engage shaft splines.
23. Continue to slide cylinder barrel forward until it
encounters the cylinder bearing (26, Figure 5-
25). Lifting the driveshaft slightly helps cylinder
barrel (10) and cylinder bearing engagement.
Continue pushing cylinder forward until the pis-
ton shoes contact swashblock (25).
24. At this point, the back of the cylinder barrel
should be located approximately 6.3 mm (0.25
in.) inside the back of the pump housing.
L5-38
Control Piston Group
25. Install piston rings (2 & 3, Figure 5-25) into their
respective grooves on control piston (11) using
care to assure they are in proper location.
26. Insert control piston assembly into sleeve (4).
27. While supporting the control piston, press or slip
in pin (8) and secure with cotter or roll pin (18).
28. Order of piston sleeve seal installation starts at
widest end of sleeve.
29. Install backup ring (1, Figure 5-28) and O-ring
(2) and backup ring (3) in rear most groove on
piston sleeve. Install O-ring (4) and backup ring
(5) in remaining groove.
FIGURE 5-28. O-RING LOCATION ON PISTON
1. Backup Ring
2. O-Ring
3. Backup Ring
30. Insert piston and sleeve assembly (4, Figure 5-
25) into valve plate (17, Figure 5-26).
31. Install O-ring (18) in rear of valve plate. Use four
cap screws (21) to fasten cover plate (19) over
opening in valve plate (17).
Steering Component Repair
SLEEVE
4. O-Ring
5. Backup Ring
L05035