MG MGB User Manual

THE
ENGINE
24.
25.
Fig. A.
33
3NC
96l
Fitting
a
gudgeon
pin, using
Servicetool
18G 1150 and
adaptor
set
18G 1150 D
‘A’
=
0.040 in. (1
mm.)
end-■oat.
4.
Gudgeonpin.
Remover/replacer
bush ■ange
towards
gudgeon
pin.
Under
no
circumstances
must
the ■ange be
allowed
to
contact
the
piston.
NOTE.—If the
torque
wrench
has
not
broken
throughout
the pull,
the
fit of the gudgeon
pin
to
the
connecting
rod
is
not
acceptable
and
necessitates
the
renewal
of
components.
The
large
nut
and
centre
screw
of the tool
must
be
kept well
oiled.
Remove
the Service
tool.
Check that
the
piston pivots
freely
on
the
pin,
and
is
free‘to
slide
sideways.
If stiffness
exists,
wash
the
assembly
in
fuel
or
paraf■n
(kerosene),
lubricate
the
gudgeon pin
with
graphited
oil
(Acheson’s Colloids
‘Oildag’) and
re-check.
If
stiffness
persists
dismantle
and
check for
ingrained dirt
or
damage.
PISTON
RINGS
26.
27.
MGB.
Enter the
piston
rings
squarely
into
the
top
of
the
cylinder bore
and check the
gaps
(see
‘GENERAL
DATA’). Check the
ring
to
piston
groove
clearances.
Fit
the bottom
rail of the oil. control
ring
to
the
piston
and
position it
below
the bottom
groove.
Fit the
oil control expander
into
the bottom
groove
and
move
the bottom oil control
ring
rail
up
into
the
bottom
groove.
Fit the
top
oil control rail
into
the
bottom
groove.
Issue
2. 87518
‘B’
=
0.080 in.
(2 mm.) from piston
7.
Groove in sleeve
towards gudgeon
pin.
11.
Lubricate
thrust
race
and
screw
thread.
Check that
the ends of the expander
are
butting but
not
overlapping
(see
Fig.
A3
1)
and
set
the
gaps
of the
rails and the expander
at
90
degrees
to
each
other.
28.
Fit the thinner
of the
two
compression
rings into
the
second
groove
with the face marked
‘TOP’
uppermost.
29.
Fit the
top
compression
ring.
30.
Position
the
ring
gaps
at
90
degrees
to
each other and
away
from
the thrust side
of the
piston.
Refitting
31.
Reverse
the removal procedure
noting
the
following
points.
(a) Lubricate the
piston rings
with
graphited oil and
stagger
the
compression ring
gaps
at
90°
to
each
other.
(b)
Compress
the
piston rings using
Service
tool 18G
55 A.
(c)
Ensure
that each
connecting
rod and
piston is
refitted
into its
original bore,
the
correct
way
v
round.
((1) Check that the big-end bearings
are
correctly
located
in
the
connecting
rods
and
caps.
Use
the
special multi-sided
locknuts and tighten
to
the
torque
■gure
given in
‘GENERAL
DATA’.
A31

MG MGB Specifications

General

Brand	MG
Model	MGB
Category	Automobile
Language	English