MG MGB - Available Spacers for Differential Assembly

THE REAR AXLE AND REAR
SUSPENSION
ASQSSA
Fig.
Ha.7
Use ■ange
wrench
18G
34 A
to
hold
the
flange
against
rotation
when tightening the pinion
nut
with
torque
wrench
180
592
Clean the head of the
jig
pillar
(18G
191
J)
and
remove
the
keep disc from the base
of
the
magnet.
Position the
magnet
on
the pillar head and adjust
the dial
gauge
to
zero
when
the dial
gauge
foot
is
positioned
on
the
pillar
head
(see Fig.
Ha.9).
NOTE—The pillar is
the standard
height of the differentia
assembly of
6.972 in.
(177.10 mm.).
.-
Spin
the differential
to
settle the bearings,
move
the
arm
of
the
dial indicator
to
the machined face of the
jig
(see
Fig.
Ha.9),
and take
a
reading.
Add the
variation
to
the
standard
height
to
obtain
the total width
of the differential assembly
(see
Example B).
Subtract the total width of the
differential
assembly,
and
the
total distance collar thickness will be
found.
To this
■gure
a
further
.004
in.
(.102
mm.)
must
be added
to
give
bearing
‘pinch’
(see
Example
C).
Divide this total by
two to
obtain the distance
collars
of equal thickness
(see
Example
D). ’
Example
A
Differential
case
standard
Stamped
on case
‘A’
Stamped
on
case
‘B’
7.243
in.
(183.98 mm.)
.001 in.
(.025 mm.)
.002 in.
(.038 mm.)
Total distance
between
bores
..
7.246
in.
(184.05 mm.)
Example
B
Differential
assembly
standard
Clock
reading (positive)
6.972
in.
(177.10
mm.)
.008
in.
(.203 mm.)
Total differential
assembly
6.980
in.
(177.30
mm.)
Example
C
Total distance
between
bores
..
Minus
total differential
assembly
7.246
in.
(184.05
mm.)
6.980
in.
(177.30
mm.)
.266
in.
(6.75
mm.)
Plus
bearing
pre-load
.004
in.
(.102 mm.)
.270
in.
(6.86 mm.)
MGB. Issue3. 91427
Fig. Ha.8
Illustrates the
points from which the
calculations
must
be
made
to
determine the
spacer
thickness for the
hearings
on
each side of the
carrier
Example
D
Spacers each side
..
.270
in.+2
(6.86
mm.+2)
.135
in,
(3.43 mm.)
Available
spacers
for differential
assembly
Eighteen
spacers are
available
in .002
in.
(.051 mm.)
steps
from
0.115
in.
(2.92 mm.)
to
.149
in.
(3.77 mm.).
Refitting
The
correct
figure for
the
backlash
to
be used with
any
particular
crown
wheel and
pinion is
etched
on
the
rear
face
of the
crown
wheel
concerned. Increase the
spacer
thickness
on
the
opposite
side of
the
crown
wheel by this
amount
and decrease the
spacer
thickness
on
the
crown
wheel
side by the
same
amount
(see
Example
E).
Example
E
Backlash
.008
Spacer calculated
..
Minus backlash
.135
in.
(3.43 mm.)
.
.008
in.
(.203
mm.)
Crown
wheel side
spacer
.
.127
in.
(3.23
mm.)
Spacer calculated
..
Plus
backlash
.
.135
in.
(3.43
mm.)
.
.008
in.
(.203
mm.)
Opposite
crown
wheel
side
spacer
.
.143
in.
(3.62
mm.)
Ha.7