Komatsu 930E-2, Руководство по ремонту

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Rotating Group
The rotating group weighs approximately 30 lbs.
Extreme care must be taken not to damage cylin-
der wear face or cylinder wear plate face, bearing
diameters or piston shoes. Assistance from others
and use of proper lifting techniques is strongly
recommended to prevent personal injury.
19. To remove rotating group, firmly grasp the cylinder
barrel (10, Figure 6-14) and pull assembly outward
until cylinder spline disengages from driveshaft
spline about 2.5 in. (63.5 mm). Once clear, rotate
cylinder barrel a revolution or two to break any
contact between piston/shoe assemblies (13) and
swashblock (25) wear face.
20. Slide rotating group off the driveshaft and out of
the pump housing and place it on a clean, protec-
tive surface with piston shoes facing upward.
21. Mark each piston, its cylinder bore and location in
shoe retainer for ease of inspection and assembly.
22. Piston/shoe assemblies can be removed individu-
ally or as a group by pulling upward on shoe
retainer (27).
23. Remove fulcrum ball (12).
24. If shoe retainer springs (28) are removed, mark
which spring came from which bore as they must
be returned to that individual bore on assembly.
25. Remove the two pins (14, Figure 6-13) and pull the
cylinder bearing (26, Figure 6-14) straight out of
the pump housing.
Swashblock Group
26. Remove the two swashblock retaining pins (19,
Figure 6-13), tilt the bottom of the swashblock (25,
Figure 6-14) outward and remove the swashblock
from the pump case.
27. Saddle bearings (24) can be removed by using a
very short screwdriver or back hammer to pry
them loose; or continue to the next step for further
disassembly which will make their removal easier.
Driveshaft Group
28. Remove bearing retaining ring (3, Figure 6-13).
Use a mallet on the tail shaft and tap driveshaft (1)
out from the front of the pump housing.
29. Remove seal retainer (22) from pump housing.
Use a mallet and tap saddle (20, Figure 6-14) out
from the inside of the pump housing. Saddle bear-
ings (24) can then be easily removed and saddle
O-ring (21) may also be removed at this time.
INSPECTION
Always wear safety goggles when using solvents
or compressed air. Failure to wear safety goggles
could result in serious personal injury.
1. Clean all parts thoroughly.
2. Replace all seals and O-rings with new parts.
3. Check all locating pins for damage and all springs
for cracking or signs of fatigue.
Control Piston Group
4. Control piston (11, Figure 6-14) must slide
smoothly in sleeve (4).
5. Linkage to cradle should operate smoothly but not
loosely (with slop). Check piston and bore in
sleeve for signs of scratching or galling. Polish
with fine emery if needed.
Valve Plate Group
6. Closely examine mating faces of valve plate (11,
Figure 6-15) and cylinder barrel (10, Figure 6-14)
for flatness, scratches or grooves. If faces are not
flat and smooth, the cylinder side will “lift off” from
the port plate (valve plate) resulting in delivery
loss and damage to the pump. Replace if neces-
sary.
Rotating Group
7. Check all pump piston assemblies (13, figure
6-14) for smooth action in their bores.
8. Check piston walls and bores for scratches or
other signs of excessive wear (pistons should not
have more than a few thousandths clearance).
Replace if necessary.
9. Piston shoes must pivot smoothly, but end play
must not exceed 0.003 in (0.076 mm).
10. Check end play as follows:
L06021 Steering Circuit Component Repair L6-17