JLG M400 Service Manual Service Manual - Manual (Page 118)

SECTION 4 - BOOM & PLATFORM
4-2 – JLG Lift – 3121827
4. Remove hardware securing telescope cylinder #1 to
the fly boom section, then remove pin from fly.
5. Remove hardware securing telescope cylinder to
the base boom section.
WHEN REMOVING TELESCOPE CYLINDER FROM BOOM SEC-
TIONS. CARE SHOULD BE TAKEN NOT TO LET CYLINDER REST
ON POWERTRACK WHICH COULD CAUSE DAMAGE TO POW-
ERTRACK.
6. Using a suitable lifting device, remove telescope cyl-
inder from boom sections.
7. Using a piece of tape, mark the length of hoses and
wires from front of fly boom and bottom of base
boom for reassembly.
8. Remove hardware securing the front cover on base
boom section.
9. Loosen jam nuts on front wear pad adjustments and
loosen adjustments.
10. Remove hardware securing the front wear pads on
base boom section, remove wear pads.
11. Remove wire clamp on the inside of the fly nose.
12. Manually push the fly boom section into base boom
section to gain access to the power track attach-
ment bolts on the right side of the base boom sec-
tion.
13. Remove hardware securing the power track to the
aft end of the fly boom section.
14. Using a suitable lifting device, remove fly boom from
boom section.
15. Remove hydraulic lines and electrical cables from
power track.
16. Remove hardware securing power track to the base
boom section. Remove power track.
Inspection
1. Inspect boom pivot pin for wear, scoring or other
damage, and for tapering or ovality. Replace pin as
necessary.
2. Inspect lift and master cylinder pins for wear, scoring
or other damage, and for tapering or ovality. Ensure
pin surfaces are protected prior to installation.
Replace pins as necessary.
3. Inspect telescope cylinder rod attach pin for wear,
scoring or other damage. Replace pin as necessary.
4. Inspect inner diameter of boom pivot bushings for
scoring, distortion, wear or other damage. Replace
bushings as necessary.
5. Inspect wear pads for wear as shown in Section 4.7,
Wear Pads.
6. Inspect all threaded components for damage such
as stretching, thread deformation, or twisting.
Replace as necessary.
7. Inspect structural units of boom assembly for bend-
ing, cracking, separation of welds, or other damage.
Replace boom sections as necessary.
Assembly
1. Install power track to the attach point on the inside
of the base boom section. Secure power track with
hardware.
2. Install hydraulic lines and electrical cables into the
power track.
3. Install wear pads to the aft end of the fly section.
4. Using suitable lifting equipment, slide fly section into
the base section until power track attach point aligns
with holes in side of base section.
5. Attach the power track to the aft end of fly boom
section. Secure power track with hardware.