jcb JS 200 Series, Руководство по обслуживанию

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78 - 4
Section E
Hydraulics
9803/6400
Section E
78 - 4
Issue 1
Hydraulic Rams
Trouble Shooting (continued)
Item Symptoms Related Parts Trouble Treatment
Poor Bending is more than the • Replace with new part.
operation Piston rod specified limit. The seal and sliding part material may be
cylinder tube (Bending distortion: damaged too, so inspect. If abnormal,
Refer to maintenance standards) replace.
4-1 There is a recess • Replace with new part.
Movement Cylinder tube As above, inspect the seal and sliding
not smooth part material.
Abnormal wear, damage of sliding • Replace with new part.
Piston rod area As above, inspect the seal and sliding
cylinder rod part material.
sliding part Foreign matter intruding on piston • Remove foreign material.
and cylinder head sliding area As above, inspect the seal and sliding
part material.
4 Scratches, wear are present • Replace with new part.
Piston seal Inspect the cylinder tube inner surface
also.
Scratches, rust on inside • Remove the scratches, rust by honing or
with an oil stone and make the surface
smooth.
Cylinder tube If the scratch is deep and cannot be
repaired, replace cylinder tube.
• Replace piston seal.
Piston Nut Loose nut • Tighten to specified torque.
Valves Leak from valve • Inspect the valve leakage amount and
service.
Note: Hydraulic oil expands and contracts due to changes in temperature and pressure. Accordingly, the ram also
expands and this can be mistaken for internal leakage. When inspecting for internal leakage, do so at set conditions.
4-2
Inner oil
leakage.
Piston rod
extends when
work stops or
lowers
abnormally
during work.
Also, specified
operating
speed is not
achieved.