P5 3L Mk II Brake system
Servo-assisted brakes
are fitted. This system consists of a normal hydraulic system with the
addition of a slave master cylinder, operated by a vacuum servo unit connected
to the induction system.
As the power for this braking system is derived from the engine itself,
it is inadvisable to coast downhill with the engine stopped.
Should the servo unit fail the brakes will continue to function through
the normal hydraulic system when the brake pedal is depressed, but more
foot pressure will be required than formerly.
Brake fluid reservoir
The fluid reservoir for the hydraulic brake system, which should be checked
every 3,000 miles (5.000 kin) is mounted on the wing valance on the same
side as the brake pedal. Castrol/Girling
Brake and Clutch Fluid 'Crimson' is the only fluid which should be used
in these brakes. Should supplies of this grade not be available in certain
overseas tern-tories, a fluid complying with the SAE 70 R 3 specification,
may be used in an emergency.
Brake fluid reservoir,
4-speed model illustrated
The reservoir cap incorporates a float and level switch which operates
the rectangular amber warning light adjacent to the handbrake, should
the level in the reservoir fall below the safe limit.
When removing reservoir cap do not disconnect the wires; however, care
should be taken when withdrawing the float unit, to ensure that the brake
fluid does not drip on to the car, The correct level is with the reservoir
filled to the rib on the filter.
The rectangular amber warning light operates in two ways as follows:
1. It gives, when the ignition is on, visual indication that the handbrake
is applied. Before starting to drive off, ensure that the light is extinguished
by releasing the handbrake.
2. It is also used to indicate that the level of the brake fluid in the
reservoir has dropped below the safe limit. Should, therefore, the light
come on at any time when the handbrake is off, immediately investigate
the cause; in this event the level in the brake reservoir tank must in
any case be checked and replenished if necessary.
Check operation of reservoir level safety switch every 3,000 miles (5.000
kin) as follows:- Ignition 'on', handbrake 'off': unscrew and lift filler
cap, when the warning light should be illuminated.
Foot brake adjustment
When brake lining wear has reached a point where the pedal travel becomes
excessive, it is necessary to adjust the shoes in closer relation to the
drum.
Proceed as follows:
Front
Hydraulic disc brakes are fitted on the front, and the correct brake adjustment
is automatically maintained; no provision is therefore made for adjustment.
Check the thickness of front brake pads and renew if the minimum thickness
is less than 1/8 in. (3 mm).
Rear
Check and if necessary adjust the rear brake shoes every 3,000 miles (5.000
km).
They are adjusted by means of a single adjuster assembly fitted at the
forward side of the brake anchor plate which allows the shoes to expand
or contract equally.
Rear wheel brake
adjustment
1. With the rear wheels jacked tip. ensure that they rotate freely; slacken
the adjuster if necessary, by turning anti-clockwise.
2. Apply the foot brake to ensure that the shoes are bedded in and turn
the adjuster clockwise until the liningsbrush the brake drum, then slacken
adjuster off two clicks.
Hand brake adjustment
This is done automatically as the rear brakes are adjusted.
Bleeding the brake system
If the level of fluid in the reservoir is allowed to fall too low, or
if any section of the brake pipe system is disconnected, the brakes will
feel "spongy", due to air having been absorbed into the system.
This air lock must be removed by bleeding the hydraulic system at the
wheel cylinders; bleeding must always be carried out at all wheels, irrespective
of which portion of the pipe-line is affected:-
1. Slacken the shoe adjusters right off. Rear brakes only.
2, Attach a length of rubber tubing to the bleed nipple on the wheel unit
farthest from the brake pedal and place the lower end of the tube in a
glass jar containing brake fluid.
Brake bleed nipple
3. Slacken the bleed screw and pump the brake pedal sharply two or three
times and then more slowly, pausing at each end of each stroke, until
the fluid issuing from the tube shows no signs of air bubbles when the
tube is held below the surface of the fluid in the jar.
4. Hold the tube under the fluid surface and, with foot brake fully depressed,
tighten the bleed screw.
5. Repeat for the other three wheels in turn, finishing at the one nearest
the brake pedal.
6. Readjust the rear brakes.
The fluid in the reservoir should be replenished throughout the operation,
to prevent another air lock being formed.
Air filter for brake servo
The brake servo unit air filter element must be replaced every 12,000
miles (20.000 kin) as follows:
(a) Spring off retainer, remove plastic cover and filter element.
(b) Fit new filter element, replace metal cover and spring the retainer
back into position.
Air filter for brake
servo unit
Clutch,
4-speed gearbox
The clutch, which is hydraulically used when starting the car from rest
at all other times the foot should be operated, must only be or when changing
gear; kept clear of the clutch pedal to avoid unnecessary lining wear.
Clutch master cylinder
fluid and reservoir
The hydraulic clutch system comprises a pendant foot pedal, mounted in
the dash and operating a combined master cylinder and fluid reservoir,
which in turn is connected by pipes to the slave cylinder fitted adjacent
to the bell housing. The slave' cylinder is connected to the clutch lever
by means of an adjustable push rod. The fluid reservoir level should be
checked every 3,000 miles
(5.000 km). Top up as necessary to the level mark on the reservoir body.
Castrol/Girling Brake and Clutch Fluid 'Crimson' is the only fluid which
should be used. Should supplies of this grade not be available in certain
overseas territories, a fluid complying with the SAE 70 R 3 specification,
may be used in an emergency.
Clutch adjustment
To ensure efficient operation of the clutch unit, there must be free
movement at the pedal to the extent of 3/4 in. (20 mm).
Check, and if necessary adjust the clutch free pedal movement every 3,000
miles (5.000 km).
Adjustment must be made at the slave cylinder push rod and the rod between
the clutch lever and c ranked lever as follows:
(a) Slacken locknut.
(b) Adjust the push rod with the fingers until the movement is correct.
(c) Secure with the locknut.
Adjustment of the slave cylinder push rod must be compensated byadjustment
of the rod between the clutch lever and the cranked lever otherwise clutch
slip may result.
For example if adjustment at the slave cylinder rod is shortened by two
turns, the adjustment rod between the clutch lever and the cranked lever
must be lengthened by one turn.
The clutch foot pedal position adjustment is correctly set on initial
assembly and should not be disturbed.
Bleeding the clutch system
If the level of the fluid in the clutch reservoir is allowed to fall too
low or if the pipe has been disconnected, the clutch will not operate
correctly due to air having' been absorbed in the system.
This airlock must be removed by bleeding the hydraulic system at the slave
cylinder.
Clutch adjustment
(a) Attach a length
of rubber tubing to the bleed nipple and place the lower end of the tube
in a glass jar.
(b) Slacken the nipple and pump the clutch pedal, pausing at each end
of each stroke, until the fluid issuing from the tube shows no signs of
air bubbles when the tube is held below the surface of the fluid in the
jar.
(c) Hold the tube under the fluid surface and, with the pedal fully depressed,
tighten the bleed screw,
(d) Adjust pedal movement as necessary.
(e) The fluid in the reservoir should be replenished throughout the operation
to prevent another air lock being formed.
Fuel
pump
A dual fuel pump is fitted in the luggage boot adjacent to the top right-hand
side of the fuel tank behind the rear trim panels. The main pump will
operate immediately the ignition is switched on, so filling the carburetter
float chamber and ensuring easy starting.
The reserve pump is operated by the centre right switch on the instrument
panel and draws on approximately l~ gallons (7 litres) reserve fuel. Check
operation of reserve fuel pump every 3,000 miles (5.000 km) during road
test.
No maintenance is required for the dual fuel pump.
Fuel sediment bowl
The sediment bowl, mounted on the right-hand wing valance, provides an
additional filter between pumps and carburetter, and should be cleaned
every 6,000 miles (10.000 km).
Proceed as follows
(a) Remove the bowl by slackening the thumb screw and swinging the retainer
aside.
(b) Remove and clean filter gauze in petrol.
(c) Ensure that the sealing washer is in good condition.
(d) Replace gauze and refit bowl.
Fuel sediment bowl
Tyre pressures
Maximum tyre life and performance will be obtained only if the tyres are
maintained at the correct pressures.
Road speed tyres are fitted as standard equipment to all 3 Litre models
and the following pressures should be maintained:
Speeds up to 105 m.p.b. (168 k,p.b.) and normal loads:
Front 26. /1.8kg/cm sq
Rear 26 lb/sq.in. /1.8kg/cm sq
Speeds over 105 m.p.h.
(168 k.p.h.) and normal loads-4-speed models only:
Front 30 lb/sq.in/2.1cm sq
Rear 30 lb/sq.in/2.1cm sq
When the car is driven fully laden, the rear tyre pressures should be
increased by 4 lb/sq,in. (0,3 kg/cm sq),
Whenever possible check with the tyres cold, as the pressure is about
3 lb. (0,2 kg.) higher at running temperature.
Always replace the valve caps, as they form a positive seal on the valves.
Any unusual pressure loss in excess of 1 lb. (0,05 kg.) per week, should
be investigated and corrected.
Always check the spare wheel, so that it is ready for use at any time.
At the same time, remove embedded flints, etc., from the tyre treads with
the aid of a penknife or similar tool. Clean off any oil or grease on
the tyres, using petrol sparingly.
Changing wheel positions
It is recommended that the wheels are changed round every 3,000 miles
(5.000 km) as illustrated, to equalise tyre wear.
Changing wheel positions
Wheel and tyre
balance
Wheel and tyre units are accurately balanced on initial assembly with
the aid of clip-on weights secured to the wheel rim.
In order to obtain the important feature of dynamic balance it is advisable
that wheel balance should be checked every 6,000 miles (10.000 km); it
must always be done when new tyres are fitted.
Body
Every 12,000 miles (20.000 km) check tightness of sub-frame sect ring
bolts.
Road springs, rear
Every 12,000 miles (20.000 km) check the security of the nuts of the U-bolts
securing the axle to the springs and the rear rubber mounting fixing springs
to body; tighten as necessary.
U-bolts and rear
spring mounting
Propeller
shaft lubrication
Every 6,000 miles (10,000 km) apply one of the recommended greases at
the lubrication nipple on the sliding portion of the rear propeller shaft.
Fully sealed journals are fitted and these require no lubrication.
Propeller shaft lubrication
