JLG 110HX Service Manual - Manual (Page 85)

SECTION 2 - PROCEDURES
3120864 – JLG Lift – 2-61
Cleaning and Inspection
1. Clean all parts thoroughly.
2. Closely inspect all parts for damage, excessive wear,
cracks and chips. Replace parts as necessary.
3. Discard seals and o-rings.
4. Closely inspect bearings and bearing contact sur-
faces.
NOTE: Bearings may be re-used if, after thorough inspec-
tion, they are found to be in good condition.
Assembly
NOTE: Lubricate all seals, o-rings, cylinder of the power
plate and piston with clean hydraulic oil prior to
assembly.
1. Assemble piston (13) into power plate (21) using a
shop press, being careful not to damage the o-rings
or back-up rings. Visually align the center of the cut-
outs in piston with torque pin (8) holes in power
plate. Avoid pushing the piston all the way to the
bottom of the cylinder in the power plate. Try to keep
the top surface of the piston flush to 1/8 in. (3.2 mm)
below the machined surface of the power plate.
2. When pressing the bearing onto the shaft, press on
the inner race of the bearing and support the shaft
properly.
3. Rotating discs must be clean and dry. Worn or
heavily scored discs must be replaced.
4. Press bearing (3) into housing 1. Bearing must be
seated against shoulder in housing.
5. Before installing seal (4), lubricate lip of seal with
system hydraulic fluid or other suitable lubricant.
Face lip of seal toward outside of brake in order to
keep gear box oil or other external contaminants out
of brake. Using a shop press, install seal (4) by
pressing evenly around OD of seal. Use care to
avoid cocking seal.
6. Install shaft (7) into housing. Support inner race of
bearing (3) when pressing bearing onto shaft.
7. Install gasket 2. Align properly. After installing all
remaining brake components, install bearing (18).
Properly support shaft when pressing bearing onto
shaft.
8. Install power plate sub-assembly. Use a shop press
to evenly lower plate into position. There should be
no gap at the OD when power plate is properly
seated against housing. If a shop press is not avail-
able, use assembly bolts (22). Tighten sequentially,
one at a time, until power plate is properly seated.
Torque bolts to 50 to 60 ft. lb. (68 to 81 Nm).
9. If replacement of pressure relief valve is necessary,
install 1/2 to 3/4 turns beyond finger tight.
10. Bleed air from brake via bleeder screw.
2.22 SWING BRAKE - MICO - MACHINES
BUILT TO 1992
1. Separate end cover (34) from housing (56) by
removing capscrews (31) and lockwashers (32).
END COVER IS UNDER SPRING TENSION OF APPROXIMATELY
1,500 LB. (680 KG). THE FOUR BOLTS SHOULD BE LOOSENED
EVENLY TO RELIEVE THIS FORCE. IF A HYDRAULIC PRESS IS
AVAILABLE (3,000 LB. [1,360 KG] MINIMUM), THE COVER CAN BE
HELD IN POSITION WHILE REMOVING THE CAPSCREWS AND
LOCKWASHERS.
2. Tap cover with a soft mallet in order to dislodge
bearing from cover.
3. Remove o-ring (36), square-ring (35), pipe plug (33)
and bleeder (43) from end cover.
4. Remove piston (40) from end cover by inserting two
1/4-20 UNC bolts into threaded holes in piston. By
turning and pulling, piston can be removed from
bore.
5. Remove o-ring (38), back-up ring (39), o-ring (41)
and back-up ring (42) from piston.
6. Remove separators (49) from housing (56).
7. Remove shaft assembly, consisting of shaft (45),
discs (46, 50), friction plates (48), springs (47), snap
ring (44) and bearings (3, 54) from housing by
pressing or using a soft mallet on male end of shaft.
8. Remove springs (47) from between tabs of discs
(46, 50).
9. Remove bearings (37, 54) from shaft (45) with
appropriate bearing puller. The discs and friction
discs will then slide off male end of shaft. Remove
snap ring and shaft.
10. Remove dowel pins (53), springs (51, 52) and o-ring
(55) from housing.
Cleaning and Inspection
1. Clean all parts thoroughly.
2. Closely inspect all parts for excessive wear, cracks,
and chips. Replace parts as necessary.
3. Discard seals and o-rings.