Brakes (with controlled back off)
continued
Assembly
1
Clean all sealant from the mating faces of the drive
head and the brake piston housing.
2
Fit new seals
17
and
16
. Make sure they seat squarely
in their grooves.
3
Carefully press the piston
15
all the way into its housing
7
. Make sure the brake back off holes in the piston and
housing align.
4
Apply JCB Threadlocker and Sealer to threads of back
off pins
12
. Screw the back off pins
12
into the brake
piston and fit the springs
14
over the back off pins.
5
Place the tension bush
13
over the back off pin
12
.
Using a suitable tool (steel tube) drive the tension bush
onto the back off pin using a soft face hammer until the
circlip
11
can just be fitted.
6
Apply JCB High Strength Gasketing to the drive head
mating face, then fit the brake piston housing assembly.
Ensure that the match marks made during dismantling
are aligned.
7
Fit capscrews
9
and torque tighten to 56 Nm (42 lbf ft,
5.7 kgf m).
8
Remove the differential support.
9
Assemble the friction plates and counterplates
2
onto
the brake carrier
3
. If the original brake pack is being re-
used, return the plates to their original positions, see
'Dismantling'. Soak new friction plates in JCB Special
Gear Oil before assembly. Fit circlip
4
.
On assembly of the brake packs, the oil flow holes
B
must be aligned with each other when being fitted to
the brake plate carrier.
Note
: Item
3A
is fitted to non steer axles.
Note
: The illustration is typical only, refer to parts book or
General Bulletin 061 (G20/N.Am) for exact number of friction
and counter plates.
10
Locate the three reaction pins
5
into their grooves,
securing them with grease. Push the pins fully into their
location holes in the housing.
91 - 4
Section F
Transmission
9803/3280
Section F
91 - 4
Issue 1
Rear Axle - PD70, SD80
11
Install one counterplate
2
into the housing, then the
brake pack, then the other counterplate. Return re-used
counterplates to their original positions. Push the brake
pack fully home.
12
Apply JCB High Strength Gasketing to the mating face
of the drive head, and JCB Threadlocker and Sealer to
the threads of bolts
1
. Locate the axle arm onto the
drivehead, with the embossed word 'TOP' on the axle
arm uppermost.
13
Fit bolts
1
and torque tighten.
Note
: Check the grade of bolts fitted. Grade 8.8 should be
tightened to 244 Nm (178lbf ft, 24.9 kgf m), grade 12.9
should be tightened to 400 Nm (295 lbf ft, 40.8 kgf m).