JLG 4017RS Service Manual - Manual (Page 55)

3-15 3614RS, 4017RS
Boom
3.6 EXTEND/RETRACT CYLINDER REMOVAL/
INSTALLATION - 3614RS
The extend/retract cylinder hydraulically extends and
retracts the third boom section.
Seal kits for the extend/retract cylinders are available from
the local JLG dealer.
3.6.1 Extend/Retract Cylinder Removal
1. Remove any attachment from the quick coupler
assembly. Refer to Operation & Safety Manual.
2. Park the machine on a hard, level surface, extend the
boom to gain access to the extend/retract cylinder pin
in the third boom section, level the boom assembly,
place the transmission in (N) NEUTRAL, engage the park
brake and shut the engine OFF.
3. Place a Do Not Operate Tag on both the ignition key
switch and the steering wheel.
4. Properly support the extend/retract cylinder (6) using a
hoist or crane.
5. Label, disconnect and cap the extend/retract cylinder
hoses (7) from the extend/retract cylinder. Cap all
fittings and openings to prevent dirt and debris from
entering the hydraulic system.
6. Loosen and remove the extend/retract cylinder bracket
(8).
7. Remove one retaining ring from the mounting pin (9) at
each end of the extend/retract cylinder.
8. Remove each mounting pin and remove the extend/
retract cylinder and place in a secure location.
3.6.2 Extend/Retract Cylinder Installation
1. Install the extend/retract cylinder (6) onto the top of the
boom assembly.
2. Install one mounting pin (9) at each end of the extend/
retract cylinder and secure with retaining ring.
3. Uncap and connect the hoses (7) to the previously
labeled fittings at the extend/retract cylinder.
4. Instal the extend/retract cylinder bracket (8).
5. Properly connect the battery.
6. Start the machine and cycle the extend/retract cylinder
checking for leaks or any alignment problems.
3.7 BOOM SECTIONS ADJUSTMENT -
3614RS
3.7.1 Chain Adjustments
The chains are adjusted by tightening and/or backing off the
adjusting nuts at the threaded end of the chains. The
opposite chain adjusting nut usually must be loosened
whenever this procedure is performed.
The chains are properly adjusted whenever the following
parameters are met.
1. Start the machine, level the boom and retract the
extend/retract cylinder completely. Turn OFF engine.
2. At the bottom front of the boom section, adjust the
extend chain (10) and retract chain (11) to achieve the
proper boom measurements.
3. Loosen the jam nut on each chain clevis.
MZ7090
6
9
7
9
8
MZ7810
10
11