JLG X23J - X700AJ Service Manual - Manual (Page 30)

SECTION 3 - CHASSIS & TURNTABLE
3121448 – JLG Lift – 3-3
and progressive damage, they allow the track
to continue working. The development of the
damage indicated in point 3 leads to the
exposure of the metal cores and if they are
exposed for more than half of the track cir-
cumference, it means that it is time to replace
them. It can however still be used.
5. Cracks due to external factors
Cracks on external track surfaces (those in contact
with the ground) are often due to contact with
gravel, sharp stones, sharp materials, nails, glass,
which cause cuts. From the rubber properties point
of view, this is inevitable although it does depend on
service conditions. Cracks on the internal surface of
the circumference and on the edge of the rubber
originate from contact of the belt with the structure
of the undercarriage or with sharp concrete edges.
The increase in cracks is relatively small. Even if it
does not appear to be in good condition the track
can be used in heavy duty conditions.
Replacing The Rubber Tracks
THE GREASE CONTAINED IN THE HYDRAULIC
TRACK IS PRESSURISED. FOR THIS REASON, DO NOT
LOOSEN THE GREASING VALVE (1) BY MORE THAN 1
TURN; IF THE VALVE IS LOOSENED TOO MUCH, IT
RISKS BEING EXPELLED UNDER THE EFFECT OF
THE PRESSURE OF THE GREASE, PUTTING THE
SAFETY OF THE OPERATOR AT RISK. NEVER
LOOSEN GREASER (2).
When gravel or mud are blocked between the toothed wheel
and the track links, remove it before loosening.
Removing The Rubber Track
1. Stop the machine on solid, level land, lift it and sup-
port it in safe conditions, using the outriggers.
Figure 3-6.
2. Remove the screws and take of adjustment access
lid 3.
3. To loosen the track, slowly unscrew valve 1 in an
anti-clockwise direction for no more than one turn.
One turn of valve 1 is sufficient to loosen the track.
4. If the grease does not start to drain, turn the track
slowly.
5. Insert three steel pipes (4) inside the track in the
space between the rollers. Turn the driving wheel
backwards (5) in a way that the steel pipes proceed
with the track and engage on the track-tensioning
wheel. Apply force (6) laterally to allow the track to
run and lift it from the track-tensioning wheel.
Figure 3-7.
Installing The Rubber Track
ENSURE SAFE CONDITIONS WITH THE MACHINE
LIFTED TO PROCEED WITH MOUNTING THE
TRACKS.
1. Check that the grease contained in the hydraulic cyl-
inder has been removed.
2. Engage the track links with the toothed wheel and
position the other end of the track on the track-ten-
sioning wheel.
3. Turn the driving wheel in reverse (7) pushing the
track plate inside the frame (8).
4. Position the track using a steel pipe and turn the
driving wheel again.
5. Ensure that the track links are correctly engaged in
the toothed wheel and in the track-tensioning wheel.
6. Adjust track tension (see paragraph -Operations for
loosening/tightening the track).
7. Rest the tracked under-carriage on the ground.
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5
6
520 202B H19