JLG 15VPSP Service Manual - Manual (Page 46)

SECTION 2 - SERVICE PROCEDURES
2-28 – JLG Lift – 3120797
17. Assemble chain sheaves on chain assembly anchor
block (attached to cylinder rod end) and attach to
mast section-2 using following steps;
a. Insert sheave pin through anchor block and cyl-
inder rod on cylinder rod end.
b. Load three 1" flatwashers onto the sheave pin on
each side of the anchor block.
c. Place sheave wheels (for wide #544 chain) on
sheave pin, one each side of anchor block.
d. On the outside of each sheave wheel, place
another 1" flatwasher, a roll pin (into the slot in
each end of the pin), and then place a sheave
pin support bar (rectangular plate with threaded
holes on each side of pin bore hole).
e. Slide the whole anchor block/cylinder assembly
with sheave pin, wheels and pin support bars
into top of mast section-2.
f. Align the threaded holes in the attach bars on
each side of the mast and attach to top of mast
section-2 using two (2) 3/8"-16UNC x 1/2" long
socket head-countersunk-flathead cap screws
each side. Coat threads with Loctite #171 and
tighten.
18. Slide mast section-2 back into section-1 until ends
are even.
MAST SECTION 3 - ASSEMBLY
NOTE: When sliding mast sections together, be careful not
to scratch or score the anodized finish in the slide
pad channels.
19. Carefully slide mast section-3 into section-2 until
ends are even.
20. Insert slide pads into the top end mast rails between
section-2 and -3, (one on each side of the mast),
with beveled surface facing inward towards section-
3.
NOTE: Before fastening and shimming the slide pad on the
top left side of the mast, install a sequence cable
bracket against the mast under the flatwasher.
21. Thread slide pad attaching bolts, two (2) 1/4"-
20UNC x 3/8" long hex head bolts, place a flat
washer under head of each bolt, through holes in
outside rail, on top of mast section-2 and into the
slide pad inserts. Thread in enough to hold pad in
place.
22. Shim per instructions in step 7, Mast Section 2 -
Assembly.
23. Insert slide pads into the bottom end mast rails
between section-2 and -3, (one on each side of the
mast), with beveled surface facing out towards sec-
tion-2.
24. Thread slide pad attaching bolts, two (2) 1/4"-
20UNC x 3/8" long hex head bolts, place a flat
washer under head of each bolt, through holes on
inside rail, on bottom end of mast section-3 and into
the slide pad inserts. Thread in enough to hold pad
in place.
25. Shim per instructions in step 7, Mast Section 2 -
Assembly.
26. Slide section-3 out the top of section-2 approxi-
mately two (2) feet.
27. Locate one (1) of the chain (bottom) anchor plates
(one with threaded holes horizontally aligned to out-
side of bracket). Attach using outer set of holes in
bottom of mast section-3 with two (2) 1/4"-20UNC x
3/4" long bolts, place a flatwasher under head of
each bolt.
28. Locate the remaining narrow chain set (#444) and
attach them to the remaining triangular shaped
anchor plate using the attach pins, flatwashers and
cotter keys.
29. Install the chain/anchor plate assembly into the top
of mast section-3, using the remaining large pin and
pin keeper. Allow to hang out the top of mast sec-
tion-3 for later assembly.
30. Insert the threaded the ends of chain assembly
(attached to top of mast section-1), into the opening
between mast section-2 and mast section-3. Slide
the threaded ends through the holes in bottom
anchor plate attached to bottom of mast section-3.
Loosely thread two (2) 3/8"-16UNC nuts onto stud
threads on each chain. Chains will be adjusted later
in assembly.
31. Assemble chain sheaves (for narrow chain assem-
bly) to top of mast section-3 as follows;
a. Place four (4) of the 1" flatwashers onto one of
the remaining sheave pins. Locate two (2) nar-
row chain sheave wheels and slide onto sheave
pin on each side of the flatwashers.
b. Slide two (2) short spacer tubes onto sheave
pin, one each end of sheave pin to outside of
sheave wheels.
c. Place two (2) sheave pin support bars, one each
end of sheave pin onto outside of spacer tubes.
Place a roll pin in the slots at each end of the
sheave pins and align with the cutouts in the pin
support bars.
d. Holding complete sheave wheel assembly, slide
assembly into top of mast section-3 and align
threaded holes in sheave pin support bars with
holes in mast rails.
e. Attach to top of mast section-3 using two (2) 3/
8"-16UNC x 1/2" long socket head-countersunk-