JLG 4017 Service Manual - Manual (Page 30)

Boom
3.6 4017
3.3.3 Third & Fourth Boom Section Removal
1. With the three boom sections setting on suitable
supports remove bolts, keeper and pin from both
sheaves on the bottom front of the second boom
section. Remove sheaves. Remove all the wear
pads, backing plates and shims from the front inside
of the second boom section. Tag each pad, backing
plate, shim and bolts from each location.
2. Remove the bolts, keeper and pin from center
sheave on the bottom rear of the third boom section.
Remove the sheave.
3. Remove the top left and right side rear wear pads,
backing plates and shims (one on each side) from
the third boom section. Loosen the bottom rear wear
pad bolts and remove the shims from the third boom
section to gain the necessary clearance to remove
the third boom section from the second boom
section. Tag each pad, backing plate, shim and bolts
from each location.
4. Place a sling around the front of the third boom
section. Lift and slid the two boom sections 3/4 of the
way out of the second boom section.Set the boom
head down on a suitable support, then center the
sling to be able to balance the two boom sections
being removed. Carefully pull the two boom sections
(1) the remainder of the way out of the second boom
section and set the two boom sections down on
suitable supports.
5. Remove the lock bolts, keeper and pin from both
sheaves at bottom rear of the second section boom.
Remove the sheave’s.
6. Remove the clip and pin holding retract chain from
bottom front of second boom section. Clean and
inspect chain. Replace if damaged.
7. Inspect the boom and welds. Consult the local JLG
distributor or the JLG Service Department if structural
damage is detected.
8. Inspect hoses, hardware, wear pads, mounting
points, chains and other components visible with the
first boom section. Replace any item if damaged.
(Refer to Section 3.4.1, 3.4.1. “Boom Chain
Inspection,” and Section 3.7.1, 3.7.1. “Wear Pad
Inspection.”)
Note: It is recommended that if any chain or hose is
damaged that ALL chains or hoses are replaced.
3.3.4 Fourth Boom Section Removal
1. With the two boom sections setting on suitable
supports remove the bolts, keeper and pin from
sheave on the front of the third boom section.
Remove the sheaves. Remove all the wear pads,
backing plates and shims from the front inside of the
third boom section. Tag each pad, backing plate,
shim and bolts from each location.
2. Remove the top left and right side rear wear pads,
backing plates and shims (one on each side) from
the fourth boom section. Loosen the bottom rear
wear pad bolts and remove the shims from the fourth
boom section to gain the necessary clearance to be
able to remove the fourth boom section from the
third boom section.Tag each pad, backing plate,
shim and bolts from each location.
3. Loosen and remove the two bolts holding the rear of
the catrack to the top of the third boom section. Lift
and push rear of hose carrier into the fourth boom
section.
4. Place a sling around the front of the fourth boom
section (2). Lift and slid the fourth boom section 3/4
of the way out of the third boom section. Set the
boom head down on a suitable support, then center
the sling to be able to balance the fourth boom
section being removed. Carefully pull the fourth
boom section the remainder of the way out of the
third boom section and set the fourth boom section
down on suitable supports.
5. Remove the clip and pin holding both extend chains
from bottom of third and fourth boom sections. Clean
and inspect chains. Replace if damaged.
MZ0760
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