MG MGB User Manual

THE IGNITION
SYSTEM
10. Remove
the
micro
adjuster
spring
clip,
unscrew
the
nut,
and
remove
the
spring
and
vacuum
control
from
the
body.
Section
13.7
EXAMINING
THE DISTRIBUTOR
In
addition
to
carrying
out
the
examination
detailed
in
Section B.5
examine
all
parts
for
wear,
deterioration,
and
thread
damage, and the
driving
dog and
rolling weights for
indentation.
Examine the
‘0’
ring
oil
seal
(if
fitted)
on
the
shank for
deterioration.
V.
cm or
unserviceable
parts
should
be
renewed.
if the
clearance between the
action
plate
shaft
and the
body bush
is
excessive
the bush
may
be renewed
as
follows:
1.
Soak the
new
bush
in
S.A.E.
30
or
40 oil
for
24 hours.
Alternatively,
place the bush
in
oil and heat
to
100°C.
(212°
F.)
for
2
hours.
Allow the
oil
to
cool and
remove
bush.
2.
Using
a
shouldered
mandrel,
press
the old bush
out
from
the inside of the
body.
3.
Insert
the
new
bush
into
the
shank
end
of
the
body
smallest diameter of the bush
leading. The
bush
will
be
a
push fit
until the large diameter
contacts
the
body.
4.
Use
a
mandrel,
vice,
press,
or
bush drawing
tool
to
press
the bush fully home
with
an
applied steady
pressure.
5.
When pressed fully home
the bush should
be
■ush
with
the
end
of
the body shank
and should
protrude
slightly
inside the body.
6. Using
the shank drain hole
as a
guide, drill through the
bush
and then
remove
all fragments of
metal.
7.
Lubricate the
action
shaft
with clean
engine
oil,
ensure
that
no
fraze
exists
around the hole
in
the shaft
through which
the driving dog
pin
passes,
and then
insert
the shaft
into
the
body shank.
8.
If
the shaft
is
a
tight
■t
in
the
body
repeat
operation
(7)
until the shaft
is
free
to rotate
without
binding.
This
is
most
important.
9.
Run the shaft
in
the
body with
a
lathe
or
test
rig
for
15
minutes,
re-lubricate the shaft,
and assemble
the
distributor.
10.
Under
no
circumstances
must
the bush
be over-bored
since
this
will
impair
the
porosity and
thereby
the
effective
lubricating
qualities
of
the bush.
Section B.8
ASSEMBLING
THE DISTRIBUTOR
Assembly
is
a
reversal of the dismantling
sequence,
but
attention
must
be
given
to
the following
points
during
assembly:
1. Lubricate the
components.
2.
Set the
micro-adjuster
to
the
mid-way
position.
MGB.
Issue
8.
80619
9‘5“
Se
Fig.
BA
The
notch in the
pulley
approaching the
T.D.C.
position for
pistons
l
and 4.
The inset
showsthe
timing
scale
5°
marks
Adjust the
contact
breaker
points
to
the
correct gap.‘
Leave the
clamp
plate
securing
bolt
slack.
After ■tting
the
distributor
to
its
housing
rotate
the
rotor
arm
until the
driving
dog
engages
the
recess
in
the
distributor
drive
from
the
camshaft. The
lugs
on
the dog
are
offset
to
ensure
correct
replacement.
ction
13.9
G
STATIC
IGNITION
TIMING
I
To
set
the
ignition timing
proceed
as
fOIIOWS:
1.
Check
the
contact
breakerfgap
setting.
2.
Rotate the
crankshaft
until
the valves of
No.
4
cylinder
are
‘rocking’ (i.e.
exhaust
valve
just
closing
and
inlet valve
just opening).
In
this
position
No.
1
cylinder
is approximately
at
T.D.C.
compression
stroke.
3.
Refer
to
the
‘GENERAL
DATA’
for the
correct
ignition
setting and
rotate
the
crankshaft
until the
notch
on
the
crankshaft
pulley
is
opposite
the
correct
pointer
on
the
timing
cover case
for the
required
setting.
The
long
pointer
indicates
T.D.C.
4.
Rotate
the
distributor
body
anti-clockwise
until the
points
are
fully
closed, then
slowly
rotate
it
in
a
clockwise
direction until the
points
just
commence
to
open.
Alternatively,
connect
a
l2-volt lamp
in parallel
with
the
contact
breaker
points
(i.e.
one
lead
to
the
LT.
terminal
and the other
to
earth),
switch
on
the
ignition
and
turn
the distributor
as
above
until the
lamp lights. This
indicates that
the
points
have
just
opened.
'
Slacken the clamp
plate
set
bolts
and
secure
the
distributor body
in
this
position
by
tightening
the
B5

MG MGB Specifications

General

Brand	MG
Model	MGB
Category	Automobile
Language	English