JLG 80HX_HX+6_HXER ANSI Service Manual User Manual
Page 50
SECTION 3 - CHASSIS & TURNTABLE
3-12
– JLG Lift –
3120271
3.4
DRIVE BRAKE, AUSCO - MACHINES
BUILT PRIOR TO 1992
NOTE: This drive brake was used on 80HX 2WD from Octo-
ber 1987 to January 1992, 80HX 4WD Prior to Febru-
ary 1991, and 80H 2WD and 4WD from October 1987
to January 1992.
Disassembly
1.
With shaft protruding downward, remove bolts (22)
alternately and evenly to reduce spring tension.
2.
Remove power plate (21) and gasket 2.
3.
Bearing (18) is pressed onto shaft (7) and must be
removed before removal of rotating discs (11) and
stationary discs 12.
4.
Further disassembly is not recommended unless
necessary for the replacement of specific parts.
5.
If further disassembly is required, remove shaft (7)
and stack sub-assembly from housing (1) by lightly
tapping or pressing on the small external spline end
of the shaft and removing the shaft, bearings and
stack from housing.
6.
Remove bearing (18), stationary disc (12), rotating
disc (11), springs (10) and primary disc 9.
7.
Remove bearing (3) from shaft using care not to
damage seal 4. Remove seal 4.
8.
Remove springs (6) and spring retainer (5) from
housing.
9.
Remove piston (13) from power plate by introducing
low pressure air (15 PSI) into hydraulic inlet. Direct
piston away from operator.
10.
Remove o-rings (15,17) and back-up rings (14,16)
from piston O.D. and I.D. grooves. Back-up rings will
be damaged and should not be removed if replace-
ment is not planned.
11.
Pressure relief valve (23) can be removed and
inspected to assure spring loaded ball moves freely
and is contamination free.
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.
4.
Closely inspect bearings and bearing contact sur-
faces. Replace as necessary.
NOTE: Bearings may be reused 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 (13) with torque pin (8) holes in power
plate (21). 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"(0.32
cm) 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 rotating discs must be replaced.
4.
Press bearings (3) into housing 1. Bearing must be
seated against shoulder in housing.