Jensen 541 User manual

Handbook of Instructions
FOR THE
JENSEN
MODEL
This handbook is published for the use and
assistance of owners of JENSEN CARS. It
embodies in a concise form the advice and
suggestions of the Company's Technical Staff
in regard to lubrication, general care, and
maintenance, together with supplementary
information regarding the necessary adjustments
which may be required from time to time.
PRICE 1216 NETT
Compiled and Published by
JENSEN MOTORS LTD.
WEST BROMWICH
ENGLAND
Telephones :
W.B. 1112-2-3
Telegrams :
" Expert "
PAGE ONE

................................................................................................................................................ Chassis No
................................................................................................................................................... Engine No
........................................................................ Registration No ............................................ ..
Original date of
delivery from Works
........................................................... .... ...........................................
PAGE TWO

Foreword
I
N COMPILING THIS BOOK some knowledge
of the operation and care of a Motor Car has
been pre-supposed, and the instructions
contained herein, will, iffollowedwithreasonable
care, enable you to obtain the maximum enjoy-
ment and satisfaction from your JENSEN Car.
Illustrations are provided to give useful
information in the simplest form, and a lubrica-
tion chart will be found on page
11.
In the rare event of any unforeseen defect or
unusual trouble developing,
it is requested that
the matter be at once brought to our notice.
The interest of Jensen Motors Ltd. in their
productions does not end with the delivery of
the Car; on the contrary,
it is the Company's
desire to keep in close touch with all Jensen
owners, and to provide for their convenience,
a Service after sales second to none.
JENSEN MOTORS LIMITED
PAGE THREE

1. Window Winder.
2. Door Handle.
3. Demister Duct.
4. Grab Ra~l.
5. Ash Tube.
6. Overdrive Switch.
7. Trafficator Switch.
8. Starter Sw~tch.
9. Fuel Gauge.
10. Choke.
11. Speedometer.
12. lgnition Warning Light.
13. Traffic Warn~ngLight.
14. Rev. Counter.
15. Demister Duct.
16. Panel Switch.
17. Oil and Water Gauge.
18. Wiper Switch.
19. Reserve Warning light.
20. Reserve Petrol Switch.
21. Screenwasher.
22. Reverse Light Switch.
23. Ignition and Lamp Switch.
24. Heater Switch.
25. Horn Push.
26. Steering wheel Adiustment.
27. Gear Control Lever.
28. Handbrake Lever.
29. Dipswitch.
30. Clutch Pedal.
31. Brake Pedal.
32. Radiator Flap Shutter
INSTRUMENTS AND CONTROLS Fig. 1

STARTING UP AND GENERAL RUNNING HINTS
Treat the new car with consideration. Although every JENSEN car
is thoroughly tested on the road, the first few hundred miles should be done at a
moderate speed. We do not tie
JENSEN owners to the monotonous observance
of an arbitrary maximum speed for a given distance, but we recommend that sus-
tained high speeds in excess of say
60 miles per hour be avoided until the car has had
reasonable time to settle down and all moving parts are freed from their
initial stiffness. The observance of these precautions will be reflected later on in
the prolonged life of the car. Under this heading, lubrication
is by far the most
important item. Many troubles are directly traceable to lack of proper lubrication
and owners will be well repaid by giving careful attention to the lubrication diagram
Page
11.
The engine attains maximum power at 3700 r.p.m. and 4000 r.p.m. should not
be exceeded.
Westrongly recommend owners who do not wish to carry out their own oiling
and greasing to take advantage, where possible, of the facilities offered by service
stations with modern lubrication equipment.
The illustration on page four shows the general arrangement of controls and
the following points should be observed in starting the engine.
(a) Ensure that the gear control lever is in neutral.
(b) Switch on the ignition and
if starting from cold, pull out switch on facia
marked
C. This operates a small electric starting carburetter which feeds
a rich mixturetoall the cylinders. Press starting switch firmly. The engine
should then start immediately.
Never Race the Engine from a cold
start-this
is most injurious.
The starting carburetter must be switched off when the engine has warmed
up. As a general guide, this will take place after
+ to 74 miles have been
covered, depending on the ambient temperature.
Fig.
2.
The fuel pump is mounted
on the
L.H. side of the engine
crank case.
(a) Outlet pipe.
(b) Drain Plug.
(c) Fuel pump inlet pipe.
(d) Hand priming Lever.
PAGE FIVE

(c) When the car has been parked for some time or if the carburetter float
chambers have been dismantled for cleaning, fuel will have to be pumped
tothe carburetter before the engine can be started. In these circumstances
operate the fuel pump hand priming lever.
(Fig. 2).
Fig. 3.
The full flow oil filter should
only be dismantled when the
filter element is to be renewed.
(a) Centre fixing bolt.
(b) Filter casing drain plug.
(c) Filter element.
(d) Oil sump Drain plug.
The change speed arrangement being conventional,
we do not propose to describe the method of engaging
and changing gear, but we give here a plan showing the
gear lever positions.
(Fig. 4.)
Fig. '4.
Overdrive.
The overdrive is an optional extra. To engage overdrive, which can only be
operated from fourth speed position, all that
is required is to pull switch on facia
marked
overdrive. No movement of the clutch or alteration of accelerator pedal
is necessary. Reverse process to return to fourth speed position.
PAGE SIX

CARE AND MAINTENANCE.
For correct lubrication of all engine parts, it is only necessary to maintain the
correct oil level in the sump. This
is ascertained by a Dipstick located on the right
hand side of the engine.
On all new or reconditioned engines, the sump and full flow oil filter should be
drained and refilled with new oil after the first 500, 1,000 and 2,000 miles. After
this the operation should be repeated every 2,000 miles to provide the best running
conditions.
There
is one drain plug in the sump and one near the bottom of the oil filter
reservoir (See (b) Fig. 3). The capacity of the engine lubrication system is 15 pints
(8.4 litres), plus 2 pints (1.13 litres) for full flow Tecalemit Filter.
Cylinder Head Nuts
After the first 500 and 2,000 miles of running, the cylinder head nuts should be
tightened. Tighten each nut a little at a time, working from the centre outwards.
This operation should be carried out when the engine
is hot. Tappets must be
checked after this operation and readjusted if necessary.
Oil Pressure.
The oil pressure gauge indicates whether the oiling system is working correctly
and
it should be looked at occasionally while the engine is running.
The normal working pressure
is 55 p.s.i. and the idling pressure is 26 p.s.i.
Should the normal oil pressure appear low, then
it is possible that the full flow Tecal-
emit oil filter
is choked and in need of renewal. Never run the engine if the oil
gauge does not register pressure as serious damage may result.
Chassis Lubrication.
The various points of the chassis should receive periodical attention as indicated
in the Lubrication Chart on Page 11. It
is of vital importance that the rear hubs
receive attention at the periods recommended, as the rear hub bearings are actually
sealed from the oil circulating in the main casing.
Rear Axle Lubrication.
The standard rear axle for this model is a Hypoid Bevel type with a ratio of
2.93
: l.
After the first 2,000 miles, drain the rear axle and refill with a recommended
type of new oil to the level of the combined oil filler and level plug. The oil level
should be checked every further 2,000 miles and topped up when necessary.
It is extremely important that only approved Hypoid oils be used with
this axle, without the use
of additives of any kind.
Gearbox Lubrication.
Drain gearbox and refill with new oil to the top level on the dipstick after the
first 2,000 miles. Access to the dipstick and oil filler plug is gained by lifting the
rubber plug in Tunnel. The capacity of the gearbox is 63 pints and if Overdrive
is fitted the combined capacity of Gearbox and Overdrive
is 8 pints, the oil level on
the gearbox dipstick remaining the same. Thz oil level should be checked every
further 2,000 miles and topped up when necessary.
PAGE SEVEN

RECOMMENDED LUBRICANTS FOR JENSEN '541'
WAKEFIELD
Engine Summer
...... ...... ......
...... Winter ...... .....
Gearbox & Overdrive ........... ......
Rear Axle (Hypoid) & Steering Box
Chassis Lubrication
& Wheel Hubs
....
(Grease Gun.) ......
Oil Can ...... ...... ...... ......
VACUUM
.... Engine Summer .... ......
...... Winter ...... ......
Gearbox & Overdrive ........ .....
Rear Axle (Hypoid) & Steering Box
Chassis Lubrication
& Wheel Hubs
(Grease G
U n .) ...... ...... ..... ......
Oil Can ...... ...... ..... ....
B.P.
Engine Summer
...... ...... ......
...... Winter ...... ......
Gearbox & Overdrive ............ ......
Rear Axle (Hypoid) & Steering Box
Chassis Lubrication
& Wheel Hubs
(Grease Gun.)
...... ......
Oil Can ...... ...... ...... .....
SHELL
...... .... Engine Summer ......
......
Winter .... .....
............ Gearbox & Overdrive ......
Rear Axle (Hypoid) & Steering Box
Chassis Lubrication
& Wheel Hubs
......
(Grease Gun.) ...... ...... ......
.....
Oil Can ...... ..... ......
ESSO
Engine Summer
...... ...... ......
...... Winter ...... ......
............ Gearbox & Overdrive ......
Rear Axle (Hypoid) & Steering Box
Chassis Lubrication
& Wheel Hubs
(Grease Gun.)
...... ...... ...... ......
Oil Can ...... ...... ...... ......
..... Castrol XL.
..... Castrolite.
...... Castrol XL.
...... Castrol H ypoy
...... Castrolrase Heavy.
...... Castrol XL.
..... Mobiloil "A".
...... Mobiloil Arctic.
...... Mobiloil "A".
.... Mobilube GX90.
...... Mobilgrease No. 4.
...... Mobiloil "A".
...... Energol SAE. 30.
...... Energol SAE. 20.
...... Energol SAE. 30.
...... Energol EP SAE. 90.
..... Energrease C3.
..... Energol SAE. 30.
.... X-100 30
...... X-100 20/20W
...... X-100 30
..... Spirax 90 EP.
...... Retinax "A"
...... X-100 30.
...... Essolube 30.
...... Essolube 20.
...... Essolube 30.
.... Esso Expee Compound 90.
.... Esso pressure Gun grease.
Essolube
30. .....
PAGE EIGHT

ADJUSTMENTS.
The engine should not require any major adjustments for at least 20,000 miles.
After this distance, should there be any falling off inefficiency,
it may be advisable
to have the cylinder head removed for decarbonising, valve grinding and tappet
adjustment. The correct tappet clearance
is .012" when the valve is closed. (Hot
or cold).
Sparking Plugs.
Sparking plugs should be removed and cleaned in a special plug cleaning machine.
After cleaning, the points should be checked and reset if necessary to the correct
gap of .035". The carburetters should be checked and cleaned. (See carburetter
section Page
19).
PAGE NINE

GENERAL DIMENSIONS ANDDATA FOR QUICK REFERENCE.
The car number will be found stamped on a plate secured to the bulkhead.
This number
is also stamped on the top of the L.H. chassis frame side member im-
mediately aft of the front suspension. The engine number is stamped on the R.H.
side of the Cylinder Block immediately below number 2 Spark Plug.
Bore
..... ......
Stroke ..... ......
......
Cubic Capacity
.....
R.A.C. Rating
Compression Ratio
...
Firing Order
Coolant Capacity
Oil Sump Capacity
Gearbox Capacity
Rear axle capacity
Fuel Tank Capacity
Overall Gear Ratios.
I st ...... ...... 9.9 : 1
2nd
...... .... 6.70 : 1
3rd
...... ..... 4.18 : 1
4th
...... ....
2.93 : 1
Reverse .... 12.0
Tyres
...... ....
...
Tyre pressure
Wheelbase
...
... Track ......
Toe-In
Camber
Caster Angle
K~ng
Pin lncl~nat~on
Overall W~dth
Overall He~ght
Overall Length
Ground Clearance
Turn~ngC~rcle
Clutch Pedal
Welght (Dry)
Centre of Grav~ty
Steer~ngratio
87 m.m. (3.4 ins.).
111 m.m. (4.37 ins.).
3,993
C.C. (243 cub. ins.).
28.2 H.P.
6.8
: 1 (Special Head 7.4 : I).
1, 5,
3, 6, 2, 4.
31 Pints.
15 Pints plus 2 Pints for full flow filter.
66 Pints (8 Pints with Overdrive).
3 Pints.
15 Gallons (12 Main
- 3 Reserve).
With Overdrive.
.... ... .... 11.98 : 1
...... .... ..... 8.14 : 1
..... .... ... 5.06 : 1
.... .... 3.54 : 1
Overdrive
... 2.75 : 1
Reverse .... 14.5 : 1
Dunlop 5.50-16 (6.40~15with wire wheels).
28 p.s.i. all round. (6.40~15-24. p.s.i.).
8 ft. 9 ins.
Front
- 4 ft. 36 ins.
Rear
- 4 ft. 34 ins.
0 ins. to ins.
1"
2
2"
6;
O
5 ft. 3 ins.
4 ft. 5 ins.
14 ft.
'10 ins.
7 ins.
34 ft.
4 ins. free movement.
26 Cwts.
49 ins. aft cf Front axle.
16
: 1. 2; turns lock to lock.
PAGE TEN

INN NO
PAGE ELEVEN

Ignition. Lucas Coil and Distributor. Automatic advance and retard.
Direction of rotation
- anti-clockwise. Contact Breaker Gap .012 ins.
Spark Plugs. Champion N.8.B. Gap ,035 ins.
Valve Clearances. .012 ins. hot or cold.
ELECTRICAL EQUIPMENT.
Lamp Bulbs.
.... Headlamps ......
......
Side Lamps .....
Number Plate ..........
.........
Reverse Lamp
.... Instrument ......
......
Warning Lamps
......
Stop & Tail ......
Flashers .... .....
Boot & Bonnet Light
60136
6w.
6w.
24w.
18 amps.
18 amps.
1816~.
24w.
6w.
Lucas No. 404.
,, ,, 989.
,, ,, 989.
P, ,, 199.
,, ,, 987.
,, ,, 987.
,, ,, 361.
,, ,, 199.
,p ,, 989.
Battery.
The Lucas 12 volt Battery Type GTWllA 64 amp. hrs. is situated below R.H.
rear seat. This location is preferable to under Bonnet fixing as fluid evaporation
is far less rapid and consequently the "topping up" operation is less frequently
required. When the acid level falls belowthe top ofthe plates, distilled water should
be added until the plates are again covered. Keep the battery terminals clean and
tight and well smeared with petroleum jelly. This will protect the terminals from
corrosion, which if allowed to continue unchecked, will result in a break in the
battery circuit.
It is important that the battery be firmly secured in its supporting brackets at
all times. When removing or replacing battery, remove clamp bar and bolts away
from well, otherwise bolts may be bent by the weight of the battery.
Headlamps.
Each headlamp incorporates a Lucas light unit which consists essentially of a
combined reflector and front glass assembly provided with a mounting flange by
means ofwhich itis secured tothe body housing. The bulb which is a Lucas Prefocus
type is located accurately in the reflector and is secured by a bayonet fixed bacl<shell,
which also provides the contact to the bulb. The design of the bulb is such that
it is correctly positioned in relation tothe reflector and no focusing is required when
a replacement bulb is fitted.
Fig.
6.
Headlight Adjusting.
A.
C and E are Reflector adjusting
screws, B
is a slotted way, and D the
Bayonet catched backshell.
PAGE TWELVE

Headlamp Alignment.
Doubledipping headlamps are used on this model and these must be set correctly
in relation tothe road and each other. Ifadjustment is necessary proceedas follows
:-
Remove the front rim by slackening the securing screw. If vertical adjustment
is required, set the light unit to the required position by means of the vertical ad-
justment screw, turn this in a clockwise direction to raise the beam and in an anti-
clockwise direction to lower it. If horizontal adjustment is required, set by means
of the two adjusting screws (one on each side ofthe light unit).
Screenwiper.
The screenwiper is ofthe heavy duty type and the motor is housed in the scuttle
above and aft ofthe heater unit. To remove the motor itwill be necessary toremove
casing above and aft of the heater which will expose a detachable plate upon which
the motor is mounted. When this panel has been removed and the rack and wiring
cables disconnected, the motor may be withdrawn.
BRAKES.
A Girling Hydraulic Braking system is used on this model and employs two
trailing shoe brakes at the front and single leading shoe brakes at the rear, all being
operated by the foot pedal in conjunction with Vacuum Servo Motor.
A handbrake
operates the mechanical linkage to the rear brakes. The supply tanks for the brake
and clutch master cylinders are integral with the cylinders and the fluid level should
be checked approximately every
2,000 miles and topped up if necessary, with Girling
Brake fluid, to within half an inch ofthe top ofthe tanks. This clearance is necessary
to allow for the expansion of the brake fluid.
Adjustment (Rear Brakes).
Noattempt should be made toadjust the brakes with the hand brake on. Means
for adjustment are available at each rear brake backing plate, whereby each shoe
can be moved to the closest proximity of the drum without actual contact. On
the rear brakes there is one adjuster between each pair ofshoes. This square ended
adjuster can be turned, a notch at a time, and the engagement, which can be heard
and felt, is caused by the flat sides of the adjuster engaging with the plungers sup-
porting the ends of the shoes. Turn the adjuster in clockwise direction as far as
it
will go. The brake shoes are then hard on and the adjuster should be turned back
one full notch to give the shoes the correct clearance from the drum. Press the
brake pedal hard once or twice to centralise the shoes in the drum.
Adjustment (Front Brakes).
The front brakes do not require adjustment as these are of the Hydrostatic
self adjusting type.
Bleeding the Brakes.
If any of the hydraulic brake system has been disconnected, it will be necessary
to bleed the system, when the connections have been reassembled, toensure that the
hydraulic fluid is free from air bubbles. There is a bleed nipple fitted on the back
of the brake backplate assembly for each expander. Connect the rubber drain tube
to one of the brake bleed nipples and immerse the open end of the tube into a jar,
partly filled with brake fluid. Then
fit a spanner on the Hexagon sides of the bleed
nipple and unscrew the nipple one full turn. The brake pedal should now be applied
repeatedly with slow full strokes until the fluid entering the jar from the drain tube
is completely free from air bubbles. The bleed nipple should now be tightened
with the spanner during a down stroke of the brake pedal. Repeat for the other
nipples.
PAGE THIRTEEN

It is important when bleeding the brakes to check the fluid level in the supply
tank at frequent intervals and to top up as necessary to ensure that the
master cylinders are never starved of fluid. Should air reach the master cylinders
it will be necessary to bleed the whole system again.
Fluid which has just been bled from the system should never be used for topping
up the supply tank immediately, since it will be, to some extent, aerated. It must,
therefore, be allowed to stand for an hour or two before it can be safely used again.
Dirty fluid must be discarded since grit or other foreign matter in the system will
seriously effect braking efficiency and cause unnecessary wear.
Servs.
Under normal conditions the Servo motor should not require attention over
long periods. However, should any trouble be experienced with the Servo,
it is
recommended that the unit be returned to the manufacturer for servicing. (See
page
28).
Care should be taken to see that the breather pipe on the Servo unit is never
left disconnected from the breather valve situated on the front of the bulkhead in
the centre of the
R.H. side, below the Servo.
FRONT SUSPENSION.
The independent front suspension is of the 'Wishbone' type, the coil springs
being held in compression between the chassis frame and the lower Wishbone.
Damping is effected by telescopic hydraulic dampers (Girling BAS6). The dampers
are of the sealed type and no attention to them should be necessary. Suspension
lubrication points are shown in the lubrication chart (See Page
11).
Alignment of Front Wheels.
Alignment of the front wheels is an importmt factor in tyre economy and ease
of steering. The front wheels should have a toe-in of between
0 ins. and &ins.
This measurement
is taken betweenthe wheel rims atthefront and rear of the wheels
at a height equal to the centre of the wheel to the ground. The rear measurement
should be between
0 ins. and ins. greater than the front measurement. If the
difference between the two measurements is other than this, the wheels are out of
alignment and adjustment should be made immediately.
To carry outthis adjustment, loosen the lock nuts on the ends of the front cross-
tube and rotate the tube in the appropriate direction to give the correct toe-in.
To permit this adjustment the cross tube carries a right-hand thread at one end and
a left-hand thread at the other end. When the correct measurement has been
obtained, retighten the two lock nuts. Do not alter setting of side tubes.
Adjusting Front Wheel Bearings.
If there is excessive play in the bearings, they can be adjusted as follows :-
Jack up the front of the car and remove the nave plates and hub caps. Remove
cotter pins from bearing nuts and tighten bearing nuts with a suitable wrench. The
bearing spacer is of the non-collapsible type and provided the bearing nut
is pulled
up tight, the correct bearing clearance will be obtained. Replace cotter pins. If
play
still exists after tightening up the hub nuts, it is probable that the bearings will
need replacement.
Lubrication of Front Wheels.
Wheel bearings should be cleaned and repacked with grease every 5,000 miles
under normal conditions.
PAGE FOURTEEN

Centre Lock Wire Wheels.
Where centre lock wire wheels are fitted it is essential that the hubs, hub nuts
and inner portion of the wheel shell are kept clean and well lubricated.
Engine oil should be used for the latter purpose and notgrease, particular atten-
tion being paid to the conical surfaces.
CARE OF TYRES.
Tyre Pressures.
The correct pressures are as follows :- 5.50 X 16:-28 p.s.i. all round.
6.40
x 15 :-24 p.s.i. all round.
For sustained high speed in excess of90 miles per hour, the tyre pressures should
be increased to 34 p.s.i. all round for 5.50
x 16, and 30 p.s.i. for 6.40~15 tyres.
Pressures (including spare) should be checked and adjusted at least weekly.
This should be done when the tyres are cold and not when they have attained normal
running temperatures. Any unusual pressure loss should be investigated
and corrected.
Under-inflation has an adverse effect on the car and causes rapid and sometimes
irregular wear. Also the casing may be damaged by excessive bending.
Changing Position of Tyres.
To obtain the best tyre mileage, equal wear, and to suppress the development
of irregular wear on front tyres, interchange front tyres with rear tyres at least
every 2,000 miles.
Tyre and Wheel Balance.
To provide smooth riding, precise steering and to avoid high speed steering
reaction, the tyres are balanced to predetermined limits. By fitting the tyre so
that the white spots near the cover bead coincide with the black spots on the tube,
a high degree of balance is achieved.
If a higher degree of balance is required, the complete tyre and wheel assembly
should be balanced.
All wheel assemblies on JENSEN cars are balanced before leaving the factory
The original balance may be disturbed after a period of running. It can be
checked, and,
if necessary, corrected by any Service Station with tyre balance
equipment.
Factors Affecting Tyre Life.
The most important factors which have an adverse affect on tyre life are :-
(l) Incorrect tyre pressures.
(2) Misalignment of wheels (See alignment of front wheels, Page 14).
(3) High average speeds. The rate of tread wear at 50 m.p.h. is nearly twice
as fast as at
30 m.p.h.
(4) Harsh acceleration.
(5) Frequent fierce braking.
(6) Warm dry weather. The rate of tread wear in summer may be twice as
fast as during a cold and wet winter.
(7) Bad road surfaces.
(8) Winding, cambered and abrasive roads. Quite moderate speeds on such
roads will produce faster tread wear than much higher speeds on straight
flat roads.
PAGE FIFTEEN

TRANSMISSION.
Clutch.
The Borg and Beck loin. diameter dry, single plate clutch has a spring cushion
drive and a total frictional area of 88 sq. ins. The clutch pedal
is isolated from the
clutch housing by means of a flexible hydraulic control.
A clearance of -& in. should
be maintained between the carbon release bearing and the pressure pad. This may
be checked by removing the clevis pin connecting the clutch release arm and the
slave cylinder connecting arm and measuring the amount of free movement at this
connecting point.
This should be
$ in. If it is other than this, adjustment may be effected by slack-
ening off clevis locknut and rotating clevis in the appropriate direction to obtain
the requisite free movement. When this has been obtained the pin should be re-
placed, split pinned and clevis locknut fully tightened.
The method of bleeding is the same as that described for the brakes on Page 13.
The clutch release bearing requires no lubrication.
Gearbox.
The gearbox provides 4 speeds forward and reverse, with synchromesh 2nd,
3rd and top gears. Ratios are as follows
:-
......
1st Gear ........... ...... 3.07:l 2nd Gear .... ..... 1.88:l
...... 3rd Gear ............ ... 1.27:l 4th Gear ...... ...... 1.OO:l
Reverse .... ...... ..... 3.07:l
Instructions for lubrication are given on Page
7.
The gearbox mainshaft is extended in a housing which allows the use of a short
propeller shaft and provides additional mainshaft bearings to give firmer positioning
for the gears.
Oil capacity
64 pints. When Overdrive
is fitted (optional extra) the combined
capacity of the gearbox and overdrive is eight pints.
Propeller Shaft.
The open propeller shaft has Hardy Spicer needle roller bearing universal joints.
Lubrication particulars for this will be found on the lubrication chart on Page 11.
Rear Axle.
The rear axle is of the semi-floating type with shim adjustment for all the
bearings and meshing of the Hypoid drive gear and pinion matched assembly. The
axle shafts are splined at the inner ends, which engage splines in the differential side
gears, while the outer ends have tapers and keys to
fit the rear wheel hubs.
The hubs are supported by taper roller bearings pressed on to the axle shafts
and located in the ends of the axle tubes. Outward thrust on either wheel is taken
by the adjacent hub bearing, whilst inward thrust is transmitted through the axle
shafts and slotted axle shaft spacer to the opposite bearing. Thus, each hub bearing
takes thrust in one direction only.
PAGE SIXTEEN

A cover on the rear of the gear carrier housingpermits the inspection and
flushing of the differential assembly without dismantling the axle.
The axle gear ratio is stamped on a tag attached to the assembly by one of the
rear cover screws. The axle serial number is stamped on the gear carrier housing
and should always be referred towhen corresponding with reference toany particulzr
unit.
In the event of trouble through any cause, wherever possible
it is strongly
recommended that use should be made of the factory reconditioning service.
It should be clearly understood that the adjustment of the Hypoid Bevel axle
is more complex than that necessary for the satisfactory performance of the spiral
bevel.
For rear axle lubrication, see instructions on Page
7.
FUEL SYSTEM.
Fuel Pump.
The fuel tank is mounted aft of the rear axle and is of 15 gallons capacity-l2
gallons main,
3 gallons reserve. The
3 gallons reserve are not metered on the gauge.
From this tank fuel is fed to the carburetter by an A.C. mechanical pump mounted
on the
L.H. side of the engine crank case. A priming lever is fitted to enable the
carburetter to be primed by hand (See Fig.
2, Page 5). This should be used if the
carburetter float chamber has just been replaced after cleaning, to save an excess of
strain on the battery through using the starter to pump fuel through the system.
Approximately every 5,000 miles the strainer gauze in the fuel pump should be re-
moved and cleaned.
Fig. 7.
This exploded view of the fuel pump,
shows the location ofthe strainer gauze.
A. Outlet pipe union.
B. Drain Plug.
C. Inlet pipe union.
D. Strainer gauze.
E. Cork washer.
F. Cover securing screw.
Access tothe strainer is gained by removingthe pumptop cover and at the same
time that the strainer gauze is removed, the pump drain plug should be unscrewed
and all sediment removed from the body ofthe Dump chamber. Use fuel and a non-
, a
fluffy rag for cleaning the chamber2,;nd for the strainer gauze use fuel only.
(See Fig.
7, Page 17).
PAGE SEVENTEEN

CARBURETTERS.
Fig. 8.
(1) Filter.
(2) Float.
(3) Float chamber secur-
ing. nut.
(4) Float needle.
(5) Air bleed.
(6) Bridge plate screw.
(7) Fast idling screw.
(8) Stop collar.
(9) Terminal Itnob.
(10) Solenoid Case.
(11) Solenoid.
(12) Plunger.
(13) Control spring.
(14) Plunger return spring.
(15) Valve flat.
(16) Valve seat insert.
(17) Olive union nut.
(18) Taper needle.
(19) Therrno jet.
(20) Fuel passage.
(21) Holding up bolt.
(22) Banjo union bolt.
(23) Float tickler pin.
Fig. 9.
' (1) Cork Gland Washer.
K(2) Slow running adjustment screw.
(3) Throttle spindle.
(4) Vacuum Ignition Union.
(5) Holding up bolt.
(6) Nut cap.
(7) Jet adjusting screw.
(8) Fibre washer.
(9) Jet lower bearing.
(10) Jet head.
(11) Brass sealing ring.
(12) Cork sealing ring.
(13) Gland spring.
(14) Main jet.
(15) Needle.
(16) Needle loclting screw.
(17) Piston.
(18) Piston spring.
(19) Suction chamber.
(20) Oil Cap,
PAGE EIGHTEEN

Fig. 10.
(1) Upper jet bearing.
(2) Main jet.
(3) Cork gland washer.
(4) Fuel Passage.
(5) Gland washer.
(6) Brass sealing ring.
(7) Jet head.
(8) Nut cap.
(9) Jet adjusting screw.
(10) Fibre washer.
(11) Jet lower bearing.
(12) Set screw.
(13) Cork sealing ring.
(14) Gland spring.
('i 5) Copper plug.
(16) Float chamber body.
(17) Copper washer.
The model '541' has three S.U. carburetters, with a smal! electrically operated
carburetter for starting. This starting carburetter which
is operated by a switch
on thefacia panel marked
'C,' supplies arichmixturetothe cylinders for easystarting.
This starting carburetter must be switched off as soon as possible after the motor
has warmed up.
The carburetters are carefully synchronised to ensure perfect running for the
engine and
it is, therefore, very important that the throttle linkage between the
carburetters is not interfered with in any way. The carburetters will also give the
best results if adjustments are only made when absolutely necessary.
Maintenance.
The only attention normally required is the monthly application of a few spots
of thin machine oil to each carburetter suction chamber oil cap. This will ensure
that the taper needle and piston assembly are free to respond readily to changes in
engine speed.
The filter in the inlet unions to each carburetter should be cleaned occasionally.
Unscrew the unions, lift off the filter, rinse in clean fuel and replace. Ensure that
the two fibre washers are in position on each side of the union.
If the running of the engine
is poor, always make sure that the trouble does not
lie elsewhere than the carburetters. Check the spark plugs and distributor contact
breaker points and see that the tappets are correctly set.
PAGE NINETEEN