Check The Re-Sequence Of The Boom Telescope (Gth-4013Ex) - Terex Genie GTH-4017 EX Service Manual

Section 4 - Maintenance Procedures
TABLE A
A-21 CHECK THE RE-SEQUENCE OF THE BOOM
TELESCOPE (GTH-4013EX)
If, during normal operation, a change in the boom extended
lengths of 150 mm or more is noticed when the boom is
retracted, proceed as follows:
1 With the thermal motor started, retract the boom fully
using the joystick, hold the system over relief (ap-
prox. 15 seconds); the three boom sections should
retract fully. Then, hold the system over relief for
approx. 20-40 seconds, to change the hydraulic oil
inside the system.
If after performing this procedure the boom still remains
out of sequence, proceed with the steps below:
2 Move the boom to the zero position, fully retract
the boom and hold the retract system over relief for
approx. 20-40 seconds.
3 Extend the boom fully, retract it and hold it over relief
for approx. 60 seconds. Repeat this operation for
maximum three times.
A
26
If, despite these procedures, the boom does not return
in sequence, check the cylinders and their re-sequence
valves A. Before this procedure, disassemble the
cylinders.
GTH-4017EX GTH-4514EX GTH-4013EX
November 2008
A
Document 57.0009.0427