Manitowoc Grove RT9130E-2 Service And Maintenance Manual page 189

RT9130E-2 SERVICE MANUAL
SYMPTOM
4. Telescope cylinder
will not retract.
5. Center mid will not
extend.
6. Center mid will not
retract.
7. Outer mid will not
extend.
8. Center mid retracts
before outer mid.
9. Outer mid extends
only a short
distance then
stops.
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, page 4-7.
Grove
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.
a. Right side check valve blocked.
a. Right side check valve closed.
a. Left side check valve is closed.
a. Right side check valve is open or
hosed backwards.
a. Left check valve is open or hosed
backwards.
Published 11-22-2016, Control # 345-12
a. Check system for leaks. Make repairs
as needed. Fill reservoir.
b. Repair or replace relief valve.
c. Reduce load. (Refer to load chart).
d. Replace check valve.
e. Replace hose or fittings. Refer to your
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.
a. Readjust, repair, or replace valve.
a. Readjust valve.
a. Readjust valve.
a. Install hoses properly.
a. Install hoses properly.
Disassembly and Assembly
Disassembly and assembly procedures of the telescope
cylinder and control valve are provided in Hydraulic System,
page 2-1 under Cylinders and Valves respectively.
BOOM
SOLUTION
broken hydraulic pump
4-27
4