MG MGB User Manual

B
THE
IGNITION
SYSTEM
Inspection
23.
Examine
the ■t
of
the drive
spindle
in its
bush, and
the
spindle
cam
for
wear.
The
automatic
advance
mechanism
should
not
be
dismantled other than
to
remove
the
control
springs.
If
any
of the
moving
parts
are
excessively
worn or
damaged,
the
complete spindle
assembly
must
be renewed.
If the
spindle bearing
is
worn
allowing excessive
side
play, the complete
distributor
must
be replaced.
24.
Check the
spring
between
the
■xed
and
movable plates.
Operate
the plate and
examine
for freedom
of
movement
and excessive
wear.
Renew
as an
assembly.
25. Examine
the
distributor and
cap
for cracks and
signs
of
tracking.
Examine
the
pick-up brush for
wear
and
freedom of
movement
in its
holder.
Renew
as
necessary.
26.
Check the
rotor
for damage,
electrode
security,
and
burning
or
tracking.
Renew
as
necessary.
3NCIO39A
Fig. 13.2
Re■tting the drive dog
(Lucas
type
45D4)
Note
the driving
tongues
(1)
are
parallel
with the
centre
line
of
the
rotor
arm
(2).
Dismantling
8.
Note
the
relative
position
of the
offset
drive
dog
to
the
rotor
arm
lobe.
The
centre
line of the drive dog
is
parallel with and offset
to
the
centre
line of the
rotor
arm.
9. Remove
the
rotor
arm.
10. Remove
the
cam
oiling
pad.
11. Remove
the
two
screws
retaining
the
vacuum
unit.
(Early
cars:
Note
that
two
prongs
protrude
downwards from
the base
plate and straddle
one
of the
retaining
screws.)
12.
Disengage
the
operating
arm
from the movable plate
and
remove
the
assembly.
13.
Push the
grommet
and‘low
tension
lead through the
body
towards
the
inside
of
the
housing.
14. Remove
the base
plate
retaining
screws.
15. Remove
the base and bearing
plate assembly.
(Early
cars:
Lever
the base plate from
its retaining
groove
in
the
body.)
16. Drive
out
the
parallel
pin retaining
the
drive
dog.
17. Remove
the drive dog and
thrust washer,
noting
that
the raised
pips
on
the washer face
the
drive
dog.
18.
Remove
the
centre
spindle complete with the
automatic
advance weights and springs.
19. Remove
the steel washer and
nylon
spacer
from the
spindle.
3NCIO4OA
.
20. Push
the
moving
contact
spring
inwards
and
unclip
the
,
low
tension
lead.
Flg’ 3'3
21. Remove‘the
screw
retaining
the earth lead
tag
and the
Re■ning the basePlate (early cars)
(Lucas
tYPe
45D4)
capacitor.
1. Base
plate.
3.
Screw
hole.
22%
Remove the
screw,
spring
and
plain
washer
retaining
2' Slotm
base
plate'
4‘ Prongs‘
,“the
■xed
contact
and
remove
the
contact
assembly.
‘A’:
Diameter checking position.
RBJO
MGB.
Issue
1. 89961
’J_

MG MGB Specifications

General

Brand	MG
Model	MGB
Category	Automobile
Language	English