Manitowoc Grove RT530E-2 Service And Maintenance Manual page 172

BOOM
SYMPTOM
4. Telescope cylinder
will not retract.
Removal And Installation
Removal and installation of the telescope cylinder from the
boom is described under disassembly and assembly of the
boom. Refer to BOOM MAINTENANCE in this Section.
4-24
PROBABLE CAUSE
a. Low hydraulic oil level.
b. Relief valve damaged.
c. Excessive load.
d. Inoperative check valve.
e. Clogged hose and fittings.
f. Broken valve spool.
g. Broken piston(s).
h. Damaged piston seals.
i. Bent boom section(s).
j. Broken hydraulic pump coupling.
k. Worn or damaged hydraulic pump.
l. Broken hydraulic pump shaft.
Published 4-22-15, Control # 556-00
RT530E-2 SERVICE MANUAL
a. Replenish oil to proper level.
b. Repair or replace relief valve.
c. Reduce load. (Refer to load chart).
d. Replace check valve.
e. Replace hose or fittings. (Refer to
Manitowoc Crane Care Parts Manual).
f. Replace valve section.
g. Replace piston(s) and all cylinder
seals.
h. Replace all cylinder seals.
i. Replace damaged boom section(s).
j. Replace
coupling.
k. Repair or replace pump.
l. Replace pump shaft.
Disassembly And Assembly
Disassembly and assembly procedures of the telescope
cylinder and control valve are provided in Section 2 under
CYLINDERS and VALVES respectively.
SOLUTION
broken hydraulic pump