MG Magnette KA, Magnette KD Instruction Manual
MISCELLANEOUS DRIVING HINTS
Do
read this Manual thoroughly and
laid down.
Do
use the gears freely, particularly on hills and when accelerating after corners,
in traffic, etc.
Do
free the engine by hand when cold before using the starter.
Do not
Do not
Do
Do please
Do
Do
Do not
Do not
Do not
race the engine when
of pistons and bearings, and may even result in piston seizure.
same time do not allow
warming up speed is 1000 r.p.m.
run the engine with the mixture control in the rich position longer than
necessary.
avoid " harsh " driving, particularly when braking ; the
smooth and powerful and need never be "stamped on."
drive slowly in the vicinity of the factory when visiting us.
retard the ignition before starting the engine.
write to us or come and see us (by appointment, please) when in any difficulty.
allow the engine to " pink."
slip the clutch except when actually starting off or changing gear ; change
down in traffic, to bottom gear if necessary.
subject the tyres to glancing blows from the kerb when drawing up beside
the pavement ; this may interfere with wheel alignment and have a serious
effect on steering and tyre life.
it
carefully and follow out the instructions
is cold ; this will shorten considerably the life
it
to idle, this is equally injurious.
M.G.
brakes are
At the
The best
Do not
Do not
Do not
Do not
Do not
Do not
Do not
Do not
Do not
Do
lean on open doors.
under any circumstances allow the oil level to fall below half full
best to keep
mix different brands of oil in the sump.
allow the engine to labour.
forget to top up the battery regularly.
forget to turn the petrol tap back to the main
the tank.
leave the headlamps alight when the car is stationary at night ; this drains
the battery unnecessarily and is very discourteous to other road users.
try to improve your car's performance by altering the ignition timing
or interfering in any way with standard settings and adjustments.
makers know best.
forget to lubricate clutch thrust.
always quote model, year, engine and chassis numbers when writing.
is
very important.
See Hints at the end of Pre-selector Gearbox section.
it
always up to three-quarters at least.
position after refilling
;
This
it
is
The
FOREWORD
The object of this lnstruction Book is to place the owner in possession of as much
detailed information as is possible concerning the
intended first of all in the early chapters to afford a pictorial survey of the chassis generally,
and the book is so arranged that all the essential information and instructions necessary
to mointain the car in efficient condition are contained in the early part. The remaining
chapters contain more detailed information which it is hoped will prove of interest to
most owners, including details of both the manual and pre-selector type gearboxes.
"
K
"
Type M.G. Magnette. It is
The time arises when
to the lnstruction Book can be of considerable value, as it points out both to the owner
and repair shops, unacquainted with the construction of the car, the correct method of
procedure.
There are a number of adjustments that have to be carried out from time to time
such as adjusting the valves and brakes, and more detailed information is given upon these
points separately. The book is provided with a comprehensive index, to which reference
should be made, as it is quite possible that either illustrations or reading matter con-
cerning the same parts may come under different headings. Should at any time the
owner fail to find the particular instruction he requires in the lnstruction Book, it is hoped
he will not hesitate to communicate with the Service Department at Abingdon, who will
always be only too ready to afford any assistonce they can at any time.
o
car has to be dismantled, and it is then that the reference
SECOND EDITION REVISED MARCH.
1934.
Page
One
IMPORTANT POINTS CONCERN1 NG LUBRICATION
The first thing that the owner will want to know concerning his car will be
the various lubricants that are recommended by the makers and the points of the
chassis that require attention. The engine oil filler is situated on the off-side of
the engine, alongside which there is a dipstick. Under no circumstances should
the car be driven fast on the lower gears or exceeding
500
on top gear during the first
oil should be drained and the base chamber refilled with new oil. The oil filters
(one in the sump and the Tecalemit unit), which will be referred to later
should be removed, the suction filter in the sump washed out with petrol, and the
spare Tecalemit element should be fitted in place of the used one.
It is inadvisable to run a cold engine fast until the oil has had an opportunity
of warming up sufficiently in order to circulate freely through the oil passage ways
throughout the engine. The pump is called upon to suck from the base chamber
or sump, oil which has become thick with standing, particularly in cold weather.
It
may be noticed that the oil gauge will show that the pressure may drop as the
speed increases
that the oil has not become sufficiently thin to pass into the pump in sufficient
quantity. The gear type pump lubricates the whole of the engine including
the valve gear.
The gcarbox and rear axle are provided with hexagon-shape filler caps.
Indication of the height level to which oil should be filled is provided, preventing
overfilling. It must be remembered that the car should not be moved in any
way when the gearbox and back axle are filled, otherwise additional lubricant may
be carried round by the teeth of the gears, thus causing the housings to contain
more oil than they need and above the proper level.
if
the engine is driven at all fast when cold. This
miles. At the end of this period the engine
40
miles an hour
is
an indication
Chassis fittings are conveniently lubricated from six oil nipples, three on either
side of the car, which are to be found on the brackets supporting the dashboard.
The bonnet has to be lifted and the nipples fed with gear oil hy means of the large
oilgun. Reference to the plates attached to the dashboard show that on the off-side
of the car there are nipples marked A, B and C, and on the near-side of the car
nipples
cables, the spring anchorages, the steering box and column and the brake cross
shaft. The brake operating spindles which pass through the brake-drums require
no lubrication. The steering head pins and the track rod and other steering
ball socket joints need lubricating separately.
D,
E
and
F.
The points lubricated by these various riipples are the brake
Only
use Shell Gear Oil in the
large oilgun.
A two-colour lubricating chart is provided herewith indicating the lubrication
that is carried out from the central dashboard nipples and is shown in black, and
the other points on the chassis that have to be individually lubricated are shown
with a red circle surrounding them, and if there is any doubt in any owner's mind
as to the exact location of the nipples, they can be seen in one or more of the
illustrations of the parts contained in this Manual. The only point that cannot be
normally seen is the clutch thrust lubricator, but this will be dealt with on page
60,
from which
the thrust can be lubricated, which requires attention every 2000 miles minimum.
it
follows that the clutch inspection cover has to be removed before
Page
Three
The following lubricants are recommended by the Company
:
Approved Engine
Oils.-Every M.G. Magnette is tested on Duckham's
Adcol "NP5" Aero and the sump and spare quart tin are filled with the same
brand when the car is issued new. We very strongly recommend the use of this
oil, both in Summer and Winter.
On the rare occasions when this oil cannot be obtained the following oils
are approved for use
:-
Duckham's Adcol " NP3 " Summer and Winter.
Wakefield Castrol
"
XL " Winter, " XXL " Summer.
Filtrate Sports Winter and Summer.
Mobiloil " AF " Winter, " D " Summer.
Pratts' Essolube Racer Summer and Winter.
Price's Motorine "C " de Luxe Summer and Winter.
Shell Triple or Aero Shell Summer and Winter.
Speedolene Aero Engine Oil Summer and Winter.
"
WW
"
Sternol
Heavy Summer and Winter.
Under no circumstances are a mineral and vegetable base oil to be
mixed in the engine.
Gearbox and Back Axle.-As
in the case of engine oils, we recommend the
use of Duckham's oil, the particular brand for the gearbox and back axle being:-
Pre-selector Gearbox.
Duckham's Adcol
"
NP3."
Filtrate S.C."
Wakefield's Castrol F."
Manual Gearbox and Back Axle.
Duckham's Gear Oil
N."
Pratts' Super Gear Oil.
Castrol Swanshot Gear Oil. Price's Motorine Amber " B."
Filtrate Gear Oil. Shell Gear Oil.
Mobiloil " C " (Gearbox " CW
").
Speedolene
"
H."
Hub Grease. Duckham's Adcol HBB."
Universal Joints.
Great care should be exercised in mixing oils at all, and
Duckham's Hardy Spicer Grease.
it
is far preferable, if
anybody wishes to run on a particular oil or is so forced by circumstances, that
the old oil should be drained out first and a complete replenishment made.
Under no circumstances should paraffin be used to wash out the lubricating
system unless the engine is being dismantled.
lubricating system of the engine will be found on pages
More detailed instructions of the
48
and 51, which deal with
the complete travel of the oil from the sump to the pump, thence through the
various pipes and passages in the engine to the main and big-end bearings and to
the overhead valve gear. The oil pump is provided with a relief valve of very
simple construction consisting of a spring and dash-pot enclosed in a cover plug.
The details of this will also be found on page 50.
We will now leave the general
lubrication summary with the advice to
only recommended oils whenever obtainable.
Keep the receptacle that is used
use
for filling clean and covered, and also wash round back axle and gearbox filler caps
before these are unscrewed.
The gearbox and back axle should be refilled
for preference after the car has been running some time, so that the
lubricant has had a chance to become fluid.
Page
Four
THE M.G. MAGNETTE
CHASSIS DETAILS
General Survey.
As soon as the owner receives his car
it
is advisable to
make himself familiar with its general mechanical details, and in order to assist in
this as much as possible,
it
has been thought advisable to take a general pictorial
survey of the chassis, in particular those parts that cannot be seen after the body
has been fitted.
The view shown in Illustration No.
it
people, but
is the view obtained by looking at a chassis from underneath.
I
is perhaps a little unconventional to some
The
petrol tank is not in position, but the undershield beneath the gearbox and front
passenger's compartment can be seen. Certain views taken from below will be
described later, more particularly the front and rear axles.
ELECTRIC
WIRES
Illustration I.-View of the M.G. Magnette chassis as seen from below. As the position of
batteries differs on models, these must be considered as of one type only. It is possible to see from
this illustration the position of the slide to obtain access through the undershield which is fitted
only with manual type gearboxes to drain the gearbox. The suspension can be examined and the
manner in which the wiring is carried out in flexible metal tubing.
It
will be noticed that the undershield is fitted with a slide, which should be
pushed forward in order to obtain access to the gearbox drain plug, which can be
removed by using a box spanner.
The body is mounted on extension brackets
attached to the outside of the frame, these extension brackets can be seen in the
illustration.
In order to obtain a better view of the chassis,
It
will also be seen that semi-elliptic springs are fitted fore and aft.
it
has been found desirable to
remove unnecessary fittings such as wings, wheels, etc.
Page
Five
Illustration
in the frame, showing the position of the dynamo and water pump,
the manner in which the frame is upswept over the axle and details
of the suspension. Note the position of the oil filter. The insert
shows the thermostat for controlling the temperature of the water.
2.-Near-side front view of the engine mounted
Illustrations Nos. 2 and 3 are two separate views of the near-side of the engine.
No.
2
particularly shows the upsweep of the frame over the front axle, the mounting
of the radiator and the two water connections to the engine. Cooling is by water
pump, which is driven direct from the timing gears. The water pump is shown
in the illustration coupled to the radiator by means of a rubber hose.
On certain models an
adjustable thermostat is fitted to control the water
temperature.
It will be seen from this illustration that the dynamo, which is placed vertically
and driven from the front end of the engine, has a coupling at its upper extremity
which in turn operates the overhead camshaft.
This illustration indicates the position of the oil relief valve, which is situated
on cop of the oil pump, and the relationship of the latter to the Tecalemit oil filter.
A
rubber buffer is placed between the frame and the front axle, and the
position where the brake cable passes through the frame will be seen, as well as
the oil pipes which lubricate the spring anchorage.
Page
Six
One small pipe in front of the engine should be noted.
This is the oil delivery
pipe from the pump to the overhead valve gear. This particular unit will be dealt
with separately.
3
Illustration No.
shows another view of the near-side of the engine and
chassis and the manner in which the exhaust manifold and water outlet pipe are
bolted to the cylinder block. It will be seen that the exhaust manifold is formed
into two branches which unite at a point underneath the undershield which is in
front of the silencer, as can be seen by referring to Illustration No. I.
Illustration
position of the self-starter operated through the solenoid. The central-
ised position of the oiling nipples will be seen on the dashboard bracket
from which pipes convey lubricant, as shown on the oiling diagram.
The electrical wires are enclosed and the cut-out and fusebox covers
have been removed to disclose these fittings on the dashboard.
The Tecalemit oil filter can be seen and the tap has been replaced
by a plug on later models.
).-Rear view of the near-side of the engine, showing
The self-starter is situated on this side of the engine, being attached to the
flywheel housing, the action of the self-starter being controlled by a solenoid.
A
number of details of the electrical equipment can be seen, including position of
the cut-out and fuses, the wires from which are carried in a covered casing.
Page
Seven
We will now pass to Illustration No.
engine, as shown when fitted in the frame.
towards the rear end of the engine, and just in front of this a dipstick is provided
in order to test the level of the oil in the engine from time to time. Whenever
the dipstick is removed, first of all wipe
be taken after removal. The oil gauge on the dashboard which indicates the engine
oil pressure is coupled up to a tap situated close to the oil dipstick, as shown in
the illustration, which makes
necessity arise.
it
possible to cut off the oil from the gauge, should
4,
which is a view of the off-side of the
The oil filler, as will be seen, is situated
it
clean, insert, and a correct reading can
Illustration 4.-General off-side view of the engine and chassis before the body is mounted.
The central lubrication nipples and pipes are clearly shown, as well as the petrol feed pipe to the
change-over tap; the bottom bowl of the Petrolift acts as a filter. It will be noted that the carburetters
are set slightly at an angle, giving access to the sparking plugs.
The lubrication details can also be studied, viz. the position of the engine oil filler and dipstick.
At the top left of the illustration, the Petrolift will be noticed, which is electric-
ally operated. The lubrication of the spring anchorages and certain other parts are
carried out from the centrally located oil nipples A,
bracket. These will be seen on referring to the oiling chart, those on the near-side
being marked
There
nipples, which are referred to in the oiling chart as A,
correct lubrication and part which each nipple supplies. The pipes can be seen in
the illustration attached to the side member of the frame. The radiator and dash-
board are tied together by means of stay rods which are adjustable.
This illustration also shows the magneto and the three carburetters in position.
The carburetters are supplied with petrol from the Petrolift, which is provided
with a filter which consists of a metal bowl at the base of the Petrolift. The
removal of the filter
pipes will be seen on the left-hand bottom corner of the illustration
situated just behind the body bracket to permit of their removal from time to time.
(Later models are fitted with a petrol pump, details of which are to be found at the end of this manual.)
Page Eight
D,
E
and
F.
is
a description upon the plate on the dashboard bracket, carrying three
is
effected by unscrewing the bottom nut. The petrol feed
B
and C attached to the dashboard
B
and
C,
indicating the
;
unions are
Momentary reference should be made to the jet control levers of the three
carburetters.
If
ever jets are adjusted,
it
is necessary to remove the pins in the
jet control rods, so as to give effect to the adjustments, but this matter will be
referred to later.
lllustration No.
5
is a close-up view of the off-side of the front of the engine
and contains a number of points with which the owner should familiarise himself.
There is first of all an oil level dipstick, which has already been referred to, the next
;
important point is the water drain tap which empties the radiator
this tap is
actually beneath the radiator and is only indicated in the illustration to draw attention
to
it.
In addition to this drain tap,
is another tap towards the rear of the cylinder block.
it
will be seen on lllustration No.
It
is necessary when draining
31
that there
the water to turn on both the taps, so as to be sure of draining the cylinder block
as well. Remove radiator cap while draining and leave
it
off
till
the radiator is
refilled.
lllustration
of the engine. The water drain tap is placed below the radiator (also shown
in lllustration No. 14). The position of the magneto drive through vernier
coupling can be studied.
from the interior of the magneto to the contact breaker and cover. Never
attempt to start the engine with the contact cover off. The jet control to the
carburetter can be seen, and if ever it is necessary to adjust the jets,
to remove the pins from the levers and adjust the equaliser rod.
5.-A
more detailed view of the components of the off-side
It
will be noted that there is an external wire coupling
it
is necessary
The magneto is mounted on a bracket and driven through a train of gears by
means of coupling with vernier adjustment, so that if ever the magneto is removed,
it
can be replaced without altering the timing gears.
It
is fitted with two points
for lubrication (this should be carried out sparingly and with special oil), the
oiling holes being covered by spring-loaded caps.
Special attention is drawn in the illustration to a wire which passes to the rear
contact breaker cover. This wire is attached to the same terminal as the earth or
switch wire, and
it
is
impossible
to start the engine
if
ever the contact breaker
cover is left off.
Page
Nine
No mention has so far been made of the lubrication details of the engine, except
the fact that oil is delivered from the pump to the overhead valves operating
mechanism. It stands to reason, of course, that oil which is so delivered will have
to be returned to the sump, and this is effected by means of two external pipes,
one of which is shown in Illustration No.
5.
The oil return conducts oil in the
magneto timing gearcase, so that this is virtually automatically lubricated.
Illustration
ing (pre-selector model); the details of all the various levers can be studied
and the location of the stop light switch.
6.-Central view of the chassis, showing the gearbox mount-
The next point in Illustration No. 5 is the steering gearbox, which is attached
to a bracket on the front cross member of the frame. It will be seen that the
steering box is lubricated from the central lubricating nipple
The next illustration, No.
6,
deals particularly with the view of the dashboard,
C.
steering column, clutch, brake, and accelerator pedals, gearbox and the general
controls of the car, including ignition control. The ignition and jet controls are
operated by two small levers situated alongside the change speed lever. The hand
brake lever is on the near-side of the gearbox.
The actual illustration is of a chassis fitted with pre-selected gearbox, and the
gear control lever will be seen at the end of the remote control tunnel.
owner should realise that the petrol tap
is
brought close to him, whereby the
The
control of the main and reserve petrol feeds can be switched over while the car
is in motion by simply turning the knob on the right-hand side of the tunnel. The
slow-running control is
marked.
The stoplight switch controlling the stoplight to the rear of the car
placed on the opposite side. Both controls are clearly
is
coupled direct to the foot brake-rod.
Page Ten
The speedometer is driven from the rear of the gearbox immediately in front
of the universal joint.
The latter is coupled to the front end of the propeller shaft
by means of a splined telescopic joint, allowing for the rise and fall of the rear axle
and the movement of the rear springs.
Continuing the general survey of the portion of the chassis which is entirely
covered by the body, reference should be made to lllustration No.
illustration, No.
8,
has been prepared to cover the lubrication points more clearly,
7.
A
separate
as well as the petrol feed line in the off-side of the frame.
lllustration No.
7
shows the gearbox attached in the frame by means of a
tubular cross member which passes through the bell housing which unites the engine
to the gearbox.
It
also shows the change speed lever and the remote control.
In order to prevent any fumes from the engine entering the driving compart-
ment of the car, the flywheel housing is fitted with a rubber ring which seals the
it
space between
and the metal covered dashboard. In both types of gearbox
employed in this chassis, the filler orifice is situated on the near-side.
The adjustment for taking up wear of the hand brake is effected by means of
a thumb screw adjuster situated at the base of the hand brake lever, clockwise
rotation being applied to tighten the brake. Extension body brackets are mounted
on the frame as shown. The electric wires from the battery are carried in a metal
conduit situated underneath the frame on the near-side. The propeller shaft is
normally entirely covered by a shaft tunnel, the forward mounting of which is shown
7.
in lllustration No.
small
oilgun is introduced to lubricate the front universal joint.
This shaft tunnel has a hole drilled in
it
through which the
lllustration
gearbox and pre-selector gear control.
overflow plug must be unscrewed so as not to overfill the gearbox.
chassis can be seen, viz. body mounting bracket, electrical wire conduits, the hand brake adjuster
and the bracket to which the shaft tunnel is mounted.
7.-View of the near-side with the central portion of the chassis showing the
The filler plug should be noted, and when this is used the
Various other details of the
Page Eleven
Gearbox extension with remote gear control showing reverse catch and speedometer
connection.
General view of manual gearbox mounted in the frame, showing oil filler and grouped
controls.
Page Twelve
Illustration
pipes and unions and the manner in which the electric wires are carried out in a conduit to the
instrument board.
and that they require lubrication occasionally through holes suitably provided.
8.-Off-side view of the
It
should be realised that universal joints are enclosed beneath the shaft tunnel,
M.G.
Magnette chassis, showing position of petrol feed
Illustration
when these are fitted forward of the axle in two 6-volt units. The tubular propeller
shaft has purposely been disconnected from the axle to indicate the flange fitting; access to
the batteries and rear axle filler and dipstick can easily be obtained under the rear seat.
9.-View of the rear end of the chassis, showing location of the batteries
Page
Thirteen
A
separate illustration, No.
8,
has been prepared to cover the lubrication points
more clearly, as well as the petrol feed line in the off-side of the frame.
It
will be seen in this illustration that the clutch pedal is directly coupled to
a lever on the gearbox by means of a rod, which in the case of pre-selected boxes
does not actually operate a clutch as in the ordinary accepted sense of the term.
it
The effect, however, is the same, as
disengages the transmission of power from
the engine to the rear axle.
The rear cross member has extensions on either side in which the rear end
of the rear springs are located, as seen in lllustration No.
9.
The petrol tank is,
in point of fact, actually supported in the body. The two petrol feed pipes couple
up the main and reserve supplies.
Illustration
end of the frame showing suspension and shock
absorber mounting.
10.-General view of the rear
lllustration No. 9 is a view of the rear end of the frame as seen after the body
has been removed.
shows the propeller shaft uncoupled from the rear axle
;
It
the position of the batteries will be noticed and the fact that two 6-volt units are
employed, coupled in series to make a 12-volt unit.
Care should be exercised
to see that the nuts which hold the battery lids in position are secure, after the
batteries have been filled up with distilled water on regular occasions. The fact that
the battery is temporarily out of sight sometimes leads to its neglect. Removal of the
rear seat pan will afford access to the batteries and to the rear axle filler, which is
combined with a level dipstick to show exactly how much oil the axle actually
contains.
10
lllustration No.
the chassis.
Particular instructions will be given subsequently of points fhat can
is the opposite view of the rear axle seen from the rear of
be seen in this illustration, including the shock absorbers, rear brakes, and spring
anchorage lubrication.
Page Fourteen
lllustration No.
particularly one side of the rear axle.
I I
is a close-up view of the rear end of the chassis, showing
It
will be noticed that there is a rubber-
lined rebound clip which limits the travel of the rear axle upwards when passing
over very bad roads, and there is a rubber buffer on the frame as well to cushion
any shock in the opposite direction. It will be seen that the shock absorbers are
mounted on a stabilising cross member, the tension of the shock absorbers being
obtained by tightening the central nut in a clockwise direction.
The brake cable passes to the anchorage underneath the axle, and the manner
In
which the rear brakes are applied can clearly be seen.
Illustration No. 12 is a view well worth studying, as
it
shows that the springs
are attached to the rear axle and the manner in which the lubrication pipes convey
oil to the points of suspension from the central dashboard nipples.
On previous illustrations the batteries are situated in front of the axle.
In
some models they are situated behind the axle in the manner shown.
Illustration I l.-Close-up view of the rear axle showing detachable cover-plate.
The shock absorbers are mounted on the cross member and the rebound of the axle
is limited by the clip.
On later models the greaser is not provided for the rear brake camshaft.
Page Fifteen
Illustration
part of the rear spring mounting.
smaller bolts preventing the leaves from separating.
will also be noted, as well as the petrol pipe unions at the rear end of the line. Rear axle drain plug
should be noted.
12.-View of the chassis as seen from below.
The springs are attached by means of four large bolts, the two
The brake cable attachments to the rear brakes
The shock absorber bracket forms
Steering.
out of view,
As the majority of the parts of the steering layout are normally
it
is as well that the owner should become familiar with the design and
principle, so as to be able to carry out his part of lubrication, and in the event of
any accidental damage occurring to see exactly how the parts are mounted. The
steering box proper is attached to a bracket on a cross member of the frame and
is fitted with a drop arm which is coupled to a transverse pull and push rod. This
will be seen in subsequent illustrations, but the view shown in Illustration No.
13
is of the steering bracket and the off-side steering arm, which is in turn coupled to
the steering head and the track rod. Every articulating joint of the steering is
fitted with an oil nipple. The track rod is threaded at either end. In fact, all the
steering rods, or, to be more exact, tubes, are threaded.
This permits of accurate
adjustment and to take care of any irregularities in the tracking of the wheels.
It is essential that anyone removing one of the divided track rods should see
that
it
is replaced the correct way round.
On examining the track rod
it
will be found that the ball joint at one end of
the rod is loaded by a coil spring, and at the other end by a coil spring washer.
The end with the double coil spring washer should be fitted to the triple
steering arm.
The end with the coil spring should be fitted to the steering knuckle arms.
The draglink from the steering gear to the triple steering arm is fitted as
standard with the long ball end at the steering gear, and the short ball end at the
triple steering arm. This could be reversed without doing any harm, but as there
is no object in reversing
it,
the standard position should be adhered to.
All steering connections should be lubricated with gear oil.
Page
Sixteen
Illustration 13.-Front end view of the frame after the engine has been removed : the brake
cables pass through the chassis as shown. The front cross member is utilised tosupport the engine
and the steering bracket is indicated: the oiling nipples on the steering rods should be examined.
Illustration 14.-View of the front end of the chassis as seen from below. The spring mounting
will be noted, including rebound spring clips. General steering lay-out can be examined, including
the pivot lever which passes through the axle body.
of the radiator drain tap and the bolts on the underneath side of the sump to secure
crankcase.
Particular note should be made of the position
it
to the
Page Seventeen
Steering on the
M.G.
Magnette differs from conventional layout. It will be
noticed that in Illustrations 13 and 14 a pivot is formed on the off-side on the
front axle between the spring perches to accommodate the main steering arm.
This special shaped arm is connected to the drop arm of the steering by means of a
short coupling tube, and its lateral movements in one direction or the other cause
the pivot lever to operate the track rods which are attached to
is
socket joints. Each of the articulating joints
provided with a lubricating nipple
it
by means of ball
which requires attention, from time to time ; in fact, reference to the oil chart shows
that they should receive lubrication by the oilgun every 1000 miles.
lllustration IS.-View of the near-side front end of the chassis, showing the steering
head and shock absorber, and sub-divided track rod with the lubricator nipples.
be seen how the brake cable passes through the frame, terminating in a rubber-covered
end. The greaser on the brake camshaft is not used on later models, and the shock
absorbers are parallel with the chassis instead of transverse.
It
will
lllustration No. 13 also affords an excellent opportunity of seeing how the
brake cables pass from inside the frame through a bracket attached to the outside
of the frame, and lubrication of these points ensures the inner brake cables being
continually lubricated.
lllustration No. 14 is a view taken from beneath the front of the car. While
it
is primarily intended to show the underneath side of the steering box, the pull
push rod, track rod, and steering arms, yet at the same time
and
it
affords an
excellent opportunity to examine the underneath side of the engine, timing case,
oil pump, extension bracket which supports the radiator, and the attachment of
the front axle to the spring by means of four bolts at each side, in addition to the
two bolts which prevent the leaves from separating.
Particular care should be taken to note the position of the radiator
drain tap.
lllustration No. 15 is a view of the front axle and near-side front wheel and
steering head. The position of the pivot pin can easily be discerned as well as the
lubricators on the pivot pin arm. The actual attachment of the shock absorbers
;
varies in different models, but the principle employed is the same
in most cases
Page Eighteen
they are attached to the wing bracket supports.
The passage of the brake cable
through the frame will be noted and also the rubber-covered end of the brake
cable.
The brake actuation lever is attached to the operating camshaft. Always
be careful to make sure when lubricating the steering head that the lubricant exudes
from the thrust races, as, in addition to lubricating the steering head pins, foreign
matter, as well as water, will be expelled.
lllustration
and the manner in which the cross shaft is supported at one end on a needle bearing.
Brakes.
in the book, and
illustrations
16.-Views of the brake cross shaft, showing the hand and foot brake adjustments.
No useful purpose will be served by including redundant illustrations
it
will already have become apparent from the examination of
Nos. 12 and 15 that the brakes are applied through the agency of steel
cables which pass through covered outer cables from either side of the centre of
the chassis to the brake-drums, the final application being shown in lllustration
No. 15.
sketch is provided on page 22 showing
diagrammatically
how the brakes are
A
applied. A cross shaft is placed in the middle of the chassis, anchored at either end,
and supported in the centre to a tubular cross member of the frame. This can be
seen by referring to lllustration No.
7,
which more particularly illustrates the hand
brake. The lever is situated on the near-side of the gearbox, and towards the base
an extension will be found on which there is a thumb nut. The foot brake adjustment
is on the off-side of the car. The brake cross shaft removed from the car is shown
in lllustration No. 16.
The foot brake pedal is coupled to the brake actuating cross shaft by a rod, and
either extremity of the brake cross shaft is provided with a pulley having holes
drilled through
it
top and bottom to receive the end adaptors of the brake cables.
As either brake is applied, the brake cross shaft is rotated, pulling the rear brake
cables forward and the front brake cables backward.
Page
Nineteen
Illustration
the thumb nuts should be turned in a clockwise direction.
17.-Details of the foot and hand brake major adjustments.
To tighten the brakes
Independent Adjustment.
Should
it
be necessary to adjust the brakes
independently this can be done by means of adjusting screws fitted to the cable
stops on the back plates. At this point on the cables a rubber dirt excluder is
fitted in the form of a rubber tube, and this tube is mounted on what is actually
the lock nut for this adjustment.
By undoing this lock nut the cable stop can be adjusted on its thread by the
amount required and the lock nut re-tightened.
The whole of the brake cross shaft is lubricated from one of the dashboard
nipples, and in order to give perfect freedom for the rotation of the cross shaft,
it
is mounted at one end on what is termed a needle or roller bearing. These are
it
shown in Illustration No. 16. Should
cross shaft,
if
care is exercised the entire bush of the needle bearings need not be
ever become necessary to remove the
removed. To reassemble the needle bearing, the inner shaft should be covered with
grease and the rollers embedded in
it,
when
it
will be found that they will stop in
position in order that they can be inserted inside the cable operating pulley.
Page
Twenty
OUTER
INDIVIDUAL
CABLE
ATTACHMENT
ADJUSTING
/
CHASSIS
BRAKE
NUT
Illustration
17a.
-
-{
5.
$
c
RUBBER
TO
EXCLUDE
COVERING
pendent brake
adiustment for
each wheel, see
text on page
Inde-
20.
The front and rear brake-drums of the car are identical in design.
from time to time to remove the brake-drums in order to clean out the brakes or
have them re-lined. The procedure is very simple.
as shown in lllustration No.
releasing the brake, the drum can be withdrawn by a slight tapping on the ribs
with a wooden mallet or a piece of wood and a hammer. The brake-drum and
its components are shown in lllustration No. 18, and in the right-hand side of the
illustration the brake-shoes with the pull-off spring can be seen.
The countersunk screw in the fluted portion of the front hub is intended to
permit the split pin of the hub nut being easily removed and replaced through the
hole in the hub, when the complete hub
18,
take off the nuts with a
is
to be removed.
When the wheel is removed
in. spanner, and after
It
is necessary
NOT
-0
0
a
-
lllustration 18.-View of front hub after the brake-drum has been
removed, showing the type of brake employed.
A
SHIM
Page
Twenty-one
Brake Anti-squeak Device.
The brake-shoes are fitted with an anti-squeak
device, which consists of lead alloy blocks fitted into the channel section of the
brake-shoes and held in position by means of clevis pins and little coil springs.
When vibrations take place in the brake-drum, they are communicated to the brake-
shoes and the shoes vibrate
the lead weights, however, are in effect " left behind
"
;
by the vibrating shoes and energy is wasted in friction between the weights and
the shoes.
The conditions under which the weights are mounted can in practice be made
such that they can always waste more energy than the squeaking forces can generate
and the squeak is prevented.
These are fully illustrated below.
Illustration 19.-Sectional view through a
brake-shoe, showing the lead weight attached to
the brake-shoe, and the various component parts
for same.
Showing diagrammatically how the brakes are applied.
Running Adjustments.
Before dealing with the detailed description and
dismantling of the various units of the chassis, the owner may require to know
particulars of adjustments which he can effect.
Illustration 20.-View
adjusting the valve clearance.
by single camshaft. By utilis
should never be undertaken
Tappet Adjustment.
of an M.G. Magnette engine, showing the operator in the act of
The removal of cover discloses the fact that the valve gear is operated
;ing an eccentric bush the valve clearance can be accurately set
unless the engine is hot.
:
this
Before the owner has had an opportunity of reading
through the whole manual he may require to adjust his valves, and in order that
he should know what is taking place, a careful examination of Illustration No.
20
will make the matter clear. He will probably be aware that there is a necessity
to have a definite clearance between the cam and the valve rocker
is
parts are distinctly marked in the illustration. It
of course important to see
;
the various
that the valve is properly seating when any adjustment is attempted, and this can
easily be seen by the position of the cam in relation to the rocker. There is a
single camshaft operating both the inlet and the exhaust valves. These are easily
distinguished from the fact that all the exhaust valves are on the near-side of the
engine and the inlet valves on the of-side of the engine. The valve rockers are
attached to separate shafts at their outer extremity, and are provided with eccentric
bushes. The opposite extremity of the rocker is wedge shaped, so that
if
the nut
which forms parts of the eccentric bush is rotated, the wedge end of the rocker
will either advance or recede from beneath the cam, and present a thicker or
thinner section to the face of the cam when this rotates. The rocker is locked in
20
position on the eccentric by means of a locking screw, and in Illustration No.
a
spanner is shown in position ready to slack off the locking set screw. The eccentric
bush can then be rotated inside the rocker boss to give the required clearance. See
that the bush does not rotate while the locking screw is being tightened.
Page Twenty-three
Correct clearance between the valve rocker and the face of the cylindrical
portion of the cam should be
illustration 2Oa.-Sectioned view of the cylinder head showing the
correct position of the rocker eccentric, and the point at which the rocker
clearance should be checked.
.006
in. when the engine is hot.
It
may be found that after grinding in valves the power will drop off unless
A
the length of the valve stem is also adjusted.
for this purpose, consisting of a horse-shoe shaped piece of metal which, when
resting on the cylinder head, gauges the exact length of the valve stem that protrudes
through the guide. Such a tool is only necessary in the case of extreme accuracy
being required, and should only be carried out by an
adjustment being capable of taking care of normal needs. It may, however, be
necessary after the valves have been ground-in several times.
THE CORRECT VALVE ROCKER CLEARANCE IS
special gauge has to be employed
M.G.
Service Depot, the ordinary
.006
in.
FOR BOTH
INLET AND EXHAUST.
Page
Twenty-four
INSTRUCTIONS
FOR TWO-CARBURETTER MODELS
MAGNETTE
(See Sectional
Carburetter.-Separate instruction concerning the S.U. is provided with
the car, but the following particulars specifically apply in the case of the
M.G. Magnette.
To afford a richer mixture for slow-running, the jet control nut should be
unscrewed.
By screwing the jet adjusting nut upwards, the petrol consumption can be
cut down if the owner is satisfied with a lesser degree of acceleration and speed,
and sometimes in hot weather general all-round better carburation can be obtained
by thus cutting down the petrol supply. Screwing up too much may cause popping
through too weak a mixture.
A
little machine oil should be injected into the dashpot or suction chamber
brass cover screw every thousand miles, to lubricate the piston guide rod
drops of machine oil is advised for this purpose.
Under no circumstances should the body of the piston be lubricated.
illustration
on Page Twenty-five)
;
three
By inserting the finger through the air inlet to the carburetter, the piston can
be lifted inside the body of the carburetter, and should rise and fall freely.
Page
xxv
The use of the strangler, or, as
it
is correctly called, the jet control, is intended
only for starting when the engine is cold, and should be employed as little as possible.
The effect of using the jet control is to enrich the mixture when starting. If
it
is
left in operation longer than is necessary the cylinder walls will be bathed with
surplus petrol, which will soon have a damaging effect on the pistons and other
parts of the engine as well.
Reference to Illustration No. 21 shows the jet control lever in position. The
jet adjustment nut is in point of fact only a stop against which the jet head rests
when the jet control lever
pulled backwards, so that
it
stands to reason that if
is
any adjustment of the jet has to be effected, this has to be carried out on each
separate carburetter.
It
follows that as all the three jet control levers are coupled
up, and if only one jet nut is unscrewed, unless the jet controls are slackened off
first,
all the other carburetters will have been adjusted similarly to any individual
one.
The two screws that hold the piston body in which the piston and suction
disc operate should be removed, so that the piston and its guide rod can be cleaned.
Extreme care should be exercised in removing the pistons, so as not to damage
the taper jet needle in any way. Mark the suction chamber before removal and
it
replace
the same way as originally fitted. Do not change the suction chambers
from one carburetter to another.
Sources of Trouble.-There are only four troubles which may affect the
functioning of the
S.U.
carburetters.
I.
The piston may be sticking and not functioning properly.
2. There may be dirt or water in the carburetter.
3.
The float mechanism may have become deranged, and the carburetter is
in consequence flooding.
The carburetters may require synchronising.
4.
Piston Sticking.-The suction piston consists of the piston proper forming
the choke ; the suction disc, into which is inserted the hardened and ground
;
piston rod working in a bearing in the suction chamber
and a tapered needle
regulating the jet opening. If the piston is sticking this can easily be ascertained
by inserting a finger in the air intake and raising the piston. The piston should
it
is
come up quite freely and return to its seat with a click as soon as
A
large percentage of the carburetters returned to the Works for correction
released.
have had the jet removed and replaced without being correctly centred. On no
account should the jet be tampered with.
It
is quite an easy matter to bend the needle if the piston is at any time removed,
it
in which case
the needle is bent-providing the jet is not out of centre-remove
will bind on the jet and cause the piston to stick. To ascertain if
it
from the piston,
refit the suction chamber on to the body of the carburetter and see if the piston
it
falls freely. If the needle is bent the only satisfactory remedy is to replace
by a
new one.
Page
xxvi
Float-chamber Flooding. This is usually obvious from the quantity of petrol
flowing over the float-chamber and dripping from the air inlet.
Flooding is generally
caused by foreign matter finding its way on to the seating of the float-chamber needle.
It
can sometimes be removed by flooding the carburetter with the tickler pin, thus
permitting the incoming petrol stream to wash away the particles of grit, otherwise
access to the needle
it
the needle
in position.
is
After taking away the guide the needle will drop straight out ; the
is
obtained by removing the float-chamber top. To take out
necessary first of all to take out the pin which holds the needle guide
seating should on no account be ground in.
Copper packing washer
-
Copper packing washer
Jet holding screw
Brass washer
An enlarged section of the jet assembly.
the junction between the jet and the jet bearing is rendered perfectly petrol-
tight by means of two cork washers which are forced against the sides of the
jet by a coil spring and conical washers. If the jet is dismantled great care must
be taken not to lose these washers.
-
Top half jet bearing
Cork gland washer
Brass washer
Bottom half jet bearing
Cork washer
Cork gland washer
Jet adjusting nut
It
will be noticed that
Synchronisation of Carburetters.-Before attempting to adjust the car-
buretters,
it
is
advisable to check over the following items.
Ignition timing.
clutch inspection opening. No. I piston
Set the I and 6 mark on the flywheel in the centre of the
is
then at T.D.C. Distributor and plug
points should be checked for cleanliness and gap, i.e. .015 in.l.020 in. on distributor
and .018 in. on plugs, also valve clearance should be .006 in. between base of cam
and rocker.
Having checked these items, remove the dashpot covers and the dashpots from
the carburetters, disconnect the jet coupling rod and screw the jet adjusting nuts
right up. On pushing the jets up to the full weak position the correct petrol level
should be
mm. below the top of the jet. If this
is
not so, and assuming the floats
I
are in good condition and not punctured, the level can be adjusted by bending slightly
Page
is
xxvii
the guide controlling the float needle, up to raise or down to lower, whichever
required.
Next proceed to set the needle in the dashpots.
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