JLG 740AJ, Руководство по обслуживанию и ремонту

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SECTION 3 - CHASSIS & TURNTABLE
3121160 3-39
28. Turn the block over. Using a press, apply pressure on the
block spring washer (50) to compress the block spring.
Compress the spring enough to safely remove the spiral
retaining ring (51). While maintaining pressure, unwind
the spiral retaining ring (51). Carefully release the pres-
sure and remove the outer block spring washer (50),
block spring (52), and inner block spring washer (53)
from the cylinder block.
Inspection
After disassembly, wash all parts (including the end-cap and
housing) thoroughly with clean solvent and allow to air dry.
Blow out oil passages in the housing and endcap with com-
pressed air. Conduct inspection in a clean area and keep all
parts free from contamination. Clean and dry parts again after
any rework or resurfacing.
PISTON
Inspect the pistons for damage and discoloration. Discolored
pistons may indicate excessive heat; do not reuse.
SLIPPERS
Inspect the running surface of the slippers. Replace any piston
assemblies with scored or excessively rounded slipper edges.
Measure the slipper foot thickness. Replace any piston assem-
blies with excessively worn slippers. Check the slipper axial
end-play. Replace any piston assemblies with excessive end-
play.
Minimum slipper foot thickness and maximum axial end-play
are given in the table below.
CYLINDER BLOCK
Measure the cylinder block height. Replace blocks worn
beyond the minimum height specification. Inspect the run-
ning surface of the cylinder block. Replace or resurface worn
or scratched blocks. Blocks may be resurfaced to the specifica-
tions shown in the drawing, provided resurfacing will not
reduce the block height below the minimum specification.
Table 3-8, Cylinder Block Measurements.
Slipper
Maximum end play
M inimum
slipper fo ot
thick ness
Table 3-7. Slipper Foot Thickness & End Play
Measurement L Frame K Frame
Slipper Foot Thickness mm
(in.) 2.71
(0.11)
4.07
(0.16)
Piston/Slipper End Play 0.15
(0.006)