JLG 15VPSP Service Manual - Manual (Page 48)

SECTION 2 - SERVICE PROCEDURES
2-30 – JLG Lift – 3120797
NOTE: Always use the an even amount of shim material
behind slide pads on both sides of the mast rails.
This will keep mast sections centered in rail chan-
nels and prevent any distortion of the section.
a. Use two shim pieces per slide pad, a thick one
and a thin one.
b. Start with a total thickness of approximately
.035" and .075" thick shim stock.
c. Attach shim stock and slide pads to both sides
of mast section-5 using five (5) 1/4"-20UNC x 1-
1/4" long, hex head cap screws per side, with
flatwasher under each bolt head. (Assemble
shim stock and slide pad to mast section rail with
shim stock against rail and slide pad with bev-
eled side out).
d. Carefully thread the slide pad mounting bolts
with flatwashers through slide pads and shim
stock into threads in mast section-5. Be certain
there are no air gaps between shims, shim and
mast or shim and slide pad when tightened.
NOTE: Mast section-5 into section-4 fit should be very snug
but still be able to be pushed together by hand. If too
tight, remove section-5, disassemble slide pad and
reduce thickness of shim stock.
e. Begin sliding top of mast section-5 with closed
rail down engaging the slide pads into slide pad
channels at bottom of mast section-4’s open rail.
Continue to push section-5 into section-4 until
BOTTOM ends of mast sections are even.
f. Check mast section for side play. If play exists
use thicker shims dividing thickness equally
between both sides of mast.
g. When mast slide pads are shimmed properly,
there should be no side to side movement of
slide pad in rail channel. Mast sections should
be very snug in channels but still be able to slide
in channel by hand.
4. Slide mast section-5 out even with top of section-4.
5. Insert threaded ends of chain assembly (attached to
top of mast section-3) into the opening between
mast section-4 and mast section-5. Slide the
threaded ends through the holes in bottom chain
anchor plate located on bottom of mast section-5.
Loosely thread two (2) 3/8"-16UNC nuts onto stud
threads on each chain. Chains will be adjusted later
in assembly.
6. Slide mast section-5 back into mast section-4 until
bottom ends of masts are even. Check to make sure
chain set attached to top of section-3 is seating
properly in cable sheave wheels attached to top of
mast section-4. (Mast section-3 may need to be
restrained to keep it’s slide pads from pushing out
the bottom of mast sections-2).
7. Adjust top and bottom ends of mast sections so they
are all even with each other. At bottom of mast
assembly, thread all chain adjusting nuts on
threaded ends until they are snug against the bot-
tom anchor plates and all slack is removed from
chains. Check that chains are seated in their sheave
wheels at top of mast assembly.
8. Assemble the mini covers to the top of each mast
section and the sequencing cables and hardware to
the side of the mast assembly.
9. Assemble the hydraulic cylinder mount to the bot-
tom of mast section-1, shim the sides of the mount
between the mount and the rail and place the rein-
forcement plate on the outside of the rail to prevent
any distortion of the mast while tightening. Attach
the hydraulic cylinder to the mount. Also attach the
PHP actuator support brackets to the cylinder mount
before inserting the mount into mast section-1.
The mast assembly should now be ready to install on
the machines base frame.
2.9 MAST TO BASE FRAME INSTALLATION
1. Using an overhead crane or suitable lifting device
capable of supporting the weight of the base frame,
attach a sling strap or chain to the front crossmem-
ber of the base frame, raise base frame.
2. Bring base frame into position in front of mast
assembly, (base frame and mast assembly must be
held at 90° angle to each other).
3. Carefully push mast assembly and base assembly
together until the four (4) holes on bottom rear of
mast align with holes in the base frame mast support
crossmember.
4. Attach mast to base using four (4) 3/8"-16UNC x 1"
long hex head bolts, locknuts and flatwashers,
(place a flatwasher under bolt head and nut and
mount with nuts on inside of frame).
5. Fasten the PHP actuator support brackets to the
PHP actuator bracket.
6. Locate the two (2) mast support braces, attach to
the brackets on the base frame using a 3/8"-16UNC
x 1" long hex head bolt, nut and flatwashers each
brace, (place a flatwasher under bolt head and nut
and mount with nuts on inside of frame. Use access
hole in bottom of frame to attach nut inside frame).
7. Before setting machine upright on base, install a
short 90° elbow fitting, flow control valve and
another short 90° elbow fitting on the end of the flow
control valve in the extend (left) port on bottom of
hydraulic cylinder. Install a long 90° elbow fitting on