[
TIlE
IGNITION
EQUIPMENT------------
Since each engine design has its
own
particular
working
temperature
and
pressure
Inside
the
cylinder.
It Is essential
that
only
sparking
plugs
recommended
by
The
M.G.
Car
Company
Ltd. be used. A plug
designed
for a
hot
dry
engine
will
not
function satls-
factorily In relatively cool oily engInes, as It will con-
stantly
oil up and cause
trouble.
On
the
other
hand,
a plug suitable for
the
oily engIne will
not
functIon
In
the
hot
type
engine
as
the
points will
overheat
and
cause pre-ignition.
The
threaded
portion
or
..
reach"
of
the
plug is
also lm
portant
since it
determines
the
position
of
the
points
In
the
combustion
chamber
and may
produce
pre-Ignition if
the
threads
on
the
plug
body
protrude
beyond
the
cylinder head.
Fig. C.7.
The
plug threads should be cleaned with a
wire
brush
to
remove deposits on
the
thread.
Section
CJ.5
CONTACT
BREAKER
MECHANISM
After
the
first 500 miles (800 km.) and
subsequently
every
3,000 miles (5000 km.) check
the
contact
breaker
as follows
:-
(0)
Turn
the
engIne until
the
contact
breaker
poInts
are
fully
opened,
and check
the
gap
with
a gauge havingathickness
of
from ·010In.
to
·012
in. (,25 rnrn,
to
·30 rnrn.) on early
models. (See Section C.14 to r later models.)
If
the
gap is
correct,
the
gauge should be a
slid
j ng fit. Do
not
alte
r
the
setti
ng unless
the
gap varies considerably from
the
gauge
thlck-
ness.
To
adjust
the
setting, keep
the
engine in
the
posltlon which gives maximum
opening
of
the
contacts and
then
slacken
the
two
screws
securing
the
fixed
contact
plate.
Adjust
the
position
of
the
plate until
the
gap is
set
to
C.6
the
thickness
of
the
gauge and
then
tighten
the
two
lockIng screws.
Remember
that
the
cam only keeps
the
contact
poi
nts
fu
lIy
open
over
10
0
and
that
care
must
be
taken
to
ensure
that
the
points
are
in
the
fully
open
position.
SCRE'WS
SECURING
CONTACT
PLATE·
Fig. C.B.
The contact breaker, showing
the
adjusting screws.
(b)
If
the
contacts
are
dirty
or
pitted.
they
must
be cleaned by polishing
them
with
a fine
carborundum
stone,
and
afterwards
wiping
them
with
a
petrol-moistened
cloth,
The
moving
contact
can be
removed
from
Its
mounting
in
order
to
assist cleaning (see
Fig.
C.9).
Check
and
adjust
the
contact
breaker
setting
after
cleaning
the
contacts.
Fig. C.9.
The
distributor
points
are
best cleaned by removing
the
rocker-arm from Its pivot and dressing the points
with a
stick of carborundum all shown,
(c)
Check
that
the
moving arm moves freely on
Its pivot. If It Is sluggish.
remove
the
moving
arm
and polish
the
pivot pin
with
a
strip
of
nne
emery
cloth.
Afterwards
clean off all
trace
of
emery
dust
and apply a
spot
of clean
engine oil
to
the
top
of
the
pivot.
M.G. Midget
(Series"
TD
"),
Issue 2 (E)
79345-1/5]
Wishvilles Classic
Automobile Library
To Next Page
Loading...
Need help?
General
