JLG 800A Service And Maintenance Manual page 80

SECTION 3 - CHASSIS & TURNTABLE
Measurement
Minimum Cylinder Block Height (A)
Cylinder Block Surface Flatness
BALL GUIDE AND SLIPPER RETAINER
Inspect the ball guide and slipper retainer for damage, discol-
oration, or excessive wear. A discolored ball guide or slipper
retainer indicates excessive heat. Do not reuse.
VALVE PLATE
The condition of the valve plate is critical to the efficiency of
the motor. Inspect the valve plate surfaces carefully for exces-
sive wear, grooves, or scratches. Replace or resurface grooved
or scratched valve plates. Measure the valve plate thickness
and replace if worn beyond the minimum specification. Valve
plates may be resurfaced to the specifications shown in the
drawing, provided resurfacing will not reduce the thickness
below the minimum specification.
3-26
Table 3-7. Cylinder Block Measurements
L25 mm (in.) L30 mm (in.)
50.8 (2.00) 50.8 (2.00)
0.002 0.002
(0.0000079) (0.0000079)
Slipper retainer
Ball guide
3.83 mm [0.151 in] min.
0.025 mm
[0.001 in]
0.0076 mm
[0.00030 in]
convex max
L35 mm (in.) K38 mm (in.)
50.8 (2.00) 54.4 (2.14)
0.002
(0.0000079) (0.0000079)
A
SWASHPLATE AND JOURNAL BEARINGS
Inspect the running face, servo ball-joint, and swashplate jour-
nal surfaces for damage or excessive wear. Some material
transfer may appear on these surfaces and is acceptable pro-
viding the surface condition meets specifications shown. Mea-
sure the swashplate thickness from the journals to the running
face. Replace swashplate if damaged or worn beyond mini-
mum specification. Replace swashplate if the difference in
thickness from one side to the other exceeds specification.
25.8 mm
LV
[1.015 in]
24.6 mm
KV
[0.969 in]
Thickness equality
side to side:
0.05 mm [0.002 in]
Inspect the journal bearings for damage or excessive wear.
Replace journal bearings if scratched, warped, or excessively
worn. The polymer wear layer must be smooth and intact.
K45 mm (in.)
54.4 (2.14)
0.002 0.002
(0.0000079)
0.0025 mm
[0.0001 in]
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