MG MGB User Manual

THE
ENGINE
A
through
the
centre
liner
and the pilot
located
in
the
rear
liner.
Secure the
cutter
and pilots
in position, ensuring
that the
locating
pin
of the
cutter
engages
the
correct
numbered
hole
in
the arbor.
Ream the
centre
liner,
release
the
cutter,
and
withdraw
the
arbor.
IMPORTANT—It is
essential that the
cutter
■utes
are
kept
clear
of swarf
at
all
times
during the cutting
operation,
preferably
with air-blast
equipment.
The
cutter
should be
withdrawn
from the liner
half-way through the
cut
and the
swarf
removed from the
cutter
and the liner.
Feed
the
reamer very
slowly, and keep
the
cutters
dry.
The arbors
should be
lightly
lubricated
before assembling
the
cutters
and
pilots.
Section A.l8
REMOVING
AND REPLACING
THE CRANKSHAFT
(Engine
Out
of
Car)
Take
off the clutch and
the
■ywheel (see
Section
A.l9),
the
timing
cover,
the
timing
wheels
and chain
(see
Section
A.lO),
the
sump
and the oil
pump
strainer
(see
Section
All),
and the
rear
engine
mounting
plate.
Remove
the big-end bearing
cap
and then take off the
main
bearing
caps
(see
Section
A.l3).
Mark
each big-end bearing
cap
and
bearing
to
ensure
that
it
is
reassembled
to
the
correct
journal,
taking
care,
in the
case
of the bearings,
that
they
are
not
damaged
or
distorted
when
marking.
Punches
should
not
be
used for this
purpose.
Lift the
crankshaft
out
of
the bearings.
Replacement
of the
crankshaft
is
a
reversal
of the above
operations.
Before replacing the crankshaft thoroughly clean
out
all
oilways.
Check the condition
of
the
rear
engine
mounting
plate oil
seal
(18GB engines)
and
renew
if
necessary.
Note
that
each
main
bearing
cap
is
stamped
with
a
common
number
which
is
also
stamped
on
the
centre
web
of
the
crankcase
near
the
main
bearing.
Section
A.l9
REMOVING AND
REPLACING
THE FLYWHEEL
(Engine
Out
of
Car)
Remove
the clutch by
unscrewing
the
six
bolts and
spring
washers
securing it
to
the ■ywheel. Release the
bolts
a
turn
at
a
time
to
avoid distortion
of the
cover
■ange.
Three
dowels
locate
the clutch
cover on
the ■ywheel.
Unlock and
remove
the
six
nuts
and three
lock plates
which
secure
the
■ywheel
to
the
crankshaft and
remove
the
■ywheel.
When replacing
the
■ywheel
ensnre
that the
1
and
4 timing
mark
on
the
periphery
of the
■ywheel
is in
line with and
on
the
same
side
as
the ■rst and
fourth
throws
of
the
crankshaft.
MGB.
Issue
4. 15676
Fig. A.27
Withdrawing the front
main bearing
cap,
using Service tool
18G
42
A
and adaptor
18G
42 B
T
o
assist
correct
location of the ■ywheel the
depression
in
the crankshaft ■ange face
is
stamped with
a
similar
timing
mark which should be
in
line with the
one on
the flywheel
periphery.
To release
the
special
■ywheel bolts the
engine
sump
and
rear
main
bearing
cap
must
also be removed.
Section A.20
FITTING
FLYWHEEL
STARTER RINGS
To
remove
the
old
starter
ring
from the ■ywheel ■ange
split the
ring
gear
with
a
cold chisel,
taking
care
not to
damage the
■ywheel.
Make
certain
that the
bore
of
the
new
rings
and
its
mating
surface
on
the
■ywheel
are
free from
burrs and
are
perfectly clean.
To ■t the
new
ring it
must
be heated
to
a
temperature
of
300
to
4000 C.
(572
to
752° F.),
indicated by
a
light-blue
surface
colour. If
this
temperature
is
exceeded the
temper
of
the teeth
will be affected. The
use
of
a
thermostatically
controlled
furnace
is
recommended. Place the heated
ring
on
the
■ywheel
with the
lead
of the
ring
teeth
facing
the
■ywheel
register.
The
expansion
will allow the
ring
to
be
■tted without force
by
pressing
or
tapping it
lightly until
the
ring is
hard
against its
register.
This
operation
should
be
followed by
natural cooling, when
the ‘shrink
■t’
will be
permanently
established and
no
further
treatment
required.
Section
A.21
REMOVING AND
REFITTING THE
ENGINE AND POWER
UNIT
It
is
possible
to
remove
the
engine
only
from the
car,
but
it
is
recommended
that the
engine
and gearbox
are
removed
together
as a
complete
assembly
thus avoiding
possible
damage
to
the clutch when separating
and re■tting
the
gearbox
to
the
engine
within
the con■nes of the
car.
A.23

MG MGB Specifications

General

Brand	MG
Model	MGB
Category	Automobile
Language	English