air condition NISSAN PULSAR 1987 Owner's Guide
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Page 91 of 238
Fuel and Engine Management 91
components, erase the self diagnosis memory as
described under the following heading.
(7) Repeat the self diagnosis test procedure and
ensure that code 12 is displayed.
To Erase Memory
(1) With the ignition Off, remove the fusible link
that is positioned third from the front of the fusible
link connecting block located at the rear of the
battery. (2) Install the fusible link after 10 seconds.
View showing the location of the fusible links.
TO CHECK AND ADJUST IGNITION TIMING
(1) Connect a timing light to the engine as
previously described under the Service Precautions
and Procedures heading.
(2) Start the engine and allow it to reach normal
operating temperature. (3) Connect a jumper lead between terminals A
and B on the diagnostic link connector. (4) With the engine idling at the specified speed,
check the ignition timing with the timing light.
The timing mark on the crankshaft pulley should
be aligned with the pointer on the inner liming belt
cover.
(5) If necessary, loosen the distributor body
retaining nuts and turn the distributor until the timing
marks are aligned. (6) Tighten the distributor body retaining nuts
and check that the timing is correct. (7) Remove the jumper lead from the diagnostic
link connector and disconnect the timing light from
the engine.
TO ADJUST BASE IDLE SPEED
NOTE: The idle speed is controlled by the
idle air control (IAC) valve and is not
adjustable. The throttle stop screw controls
the base idle speed a nd is factory set. The
following base idle speed adjustment should
only be performed if the throttle body has
been renewed, or if comprehensive testing of
related components indicates that adjust-
ment is required.
(1) Before adjusting the base idle speed perform
the following tests;
(a) Check the spark plug gaps, the high tension
leads and the ignition timin g as described previously
in the Engine Tune-up section.
(b) Check the air inlet syst em for leaks between
the throttle body and inlet manifold and the inlet
manifold and cylinder head.
NOTE; Any vacuum leaks will make the
engine idle faster than it should.
(c) Check that all wiring connectors and vacuum
hoses are securely connected. (d) Ensure that the transaxle is in Park or
Neutral. (e) Ensure that the air cleaner element is service-
able.
(2) On 1.6 liter engines, remove the air cleaner
assembly, disconnect the vacuum hose from the
throttle body and seal the vacuum hose fitting.
(3) Ensure that the throttle valve moves freely
and returns to the fully closed position when slowly
released. (4) Connect an accurate tachometer to the en-
gine as previously descri bed under the Service Pre-
cautions and Procedures heading.
(5) Start the engine and allow the engine to
warm up and the idle rpm to stabilize. Check that all
electrical accessories and the air conditioning, if
equipped, are turned off. (6) With the engine idling in Park or Neutral,
slowly disconnect the brake servo unit vacuum supply
hose from the inlet manifold. Allow the engine to run
for one minute.
Location of the base idle adjusting screw. 1.8 liter
engine.
Page 95 of 238
Fuel and Engine Management 95
(3) Disconnect the vacuum hose from the pres-
sure regulator.
(4) Release the fuel hose clamps, disconnect the
hoses from the pressure regulator and remove the
pressure regulator. Installation is a reversal of the removal procedure
ensuring that the fuel hose clamps are tightened
securely.
To Remove and Install — 1.6 Liter Engine
(1) Depressurize the fuel system as previously
described. (2) Disconnect the negative battery terminal.
(3) Remove the air cleaner assembly. If neces-
sary, refer to the Air Cleane r Assembly heading in this
section. (4) Remove the screws securing the pressure
regulator cover to the throttle body assembly. When removing the final screw hold the cover
firmly as it is under spring tension.
(5) Remove the cover, spring seat, spring and
diaphragm from the thrott le body assembly. Discard
the diaphragm.
View of the pressure regulator components removed
from the throttle body assembly. 1.6 liter engine.
Installation is a reversal of the removal procedure
with attention to the following points:
(1) Install a new diaphragm ensuring that
the
diaphragm is correctly seat ed in the groove in the
throttle body assembly. (2) Apply Loctite 262 to the threads of the
retaining screws.
(3) Place the spring seat and the spring in the
cover and install the cover to the throttle body
assembly, ensuring that the cover is positioned on the
locating dowels. (4) While holding the cover in position install
the
retaining screws and tighten securely.
NOTE: When installing the pressure regu-
lator cover ensure that the diaphragm is not
disturbed, to prevent the possibility of a fuel
leak.
INJECTORS
To Test Injector Circuit and Injectors
(1) Disconnect the injector wiring connectors.
(2) Connect a test lamp between the injector
wiring connector terminals, ensuring that the test
lamp probes do not contact each other. (3) With the ignition switched On the test lamp
should not light. On 1.8 liter engines, check each of
the other connectors.
If the test lamp lights check the wiring harness for
a short to earth between the injector wiring connec-
tor(s) and the control unit wiring connector termi-
nal - D15 and D16 on 1.8 liter engines, or D16 on
1.6 liter engines.
(4) With the aid of an assistant, operate the
starter motor. The test lamp should flash. On 1.8 liter
engines, check each of the other connectors.
If the test lamp does not flash when connected to
the injector wiring connecto r(s), proceed to operation
(6).
If the test lamp lights as described, proceed as
follows.
If the test lamp lights but fails to flash, a faulty
control unit is indicated. Pr ior to renewing the control
unit, check the condition of the injectors as follows.
(5) Connect an ohmmeter between the terminals
of the injectors).
The resistance should be more than 1.2 ohms on
1.6 liter engines or more than 12 ohms on 1.8 liter
engines.
If the injector resistance is as specified, the
injector circuit can be considered serviceable.
If the injector resistance is not as specified, renew
the faulty injector(s).
(6) With the ignition switched On, probe the
injector wiring connector terminals with a test lamp to
earth.
If the test lamp lights when the probe contacts the
pink wire terminal on 1.6 liter engines, or the white
wire terminal on 1.8 liter engines, check the wiring
harness for a short to volt age between the injector
wiring connector(s) and the control unit wiring con-
nector terminal(s) D16 on 1.6 liter engines, or D15
and D16 on 1.8 liter engines.
If the test lamp does not light when the probe
contacts the blue wire termin al on 1.6 liter engines, or
the black and red wire term inal on 1.8 liter engines,
check the EGI relay and circ uit as described under the
EG! and Fuel Pump Relays heading in this section.
If the test lamp lights when the probe contacts the
blue wire terminal on 1.6 lite r engines, or the blue and
red wire terminal on 1.8 liter engines, proceed as
follows.
(7) Switch the ignition Off and connect the
injector wiring connectors). (8) Switch the ignition On and, using a test lamp
to earth, backprobe the cont rol unit wiring connector
Page 96 of 238
96 Fuel and Engine Management
terminal D16 on 1.6 liter engines, or D15 and D16
on
1.8 liter engines.
The test lamp should light.
If the test lamp does not light check the wiring
harness for continuity between the injector wiring
connector(s) and the control unit wiring connector
terminals.
Repair or renew the wiring harness as necessary.
To Remove and Install Injectors and Fuel Rail — 1.8
Liter Engine.
(1) Depressurize the fuel system as previously
described.
(2) Disconnect the negative battery terminal.
(3) Thoroughly clean around the injectors and
View of the fuel rail, injectors and pressure regulator
removed from the engine.
the fuel rail to prevent foreign material entering the
engine.
(4) Suitably mark the fuel hoses, loosen the hose
clamps and disconnect the fuel hoses from the fuel
rail. (5) Disconnect the vacuum hose from the fuel
pressure regulator. (6) Loosen the hose clamp and disconnect the
engine ventilation hose from the throttle body. (7) Remove the bolts securing the fuel rail and
injectors to the inlet manifold. (8) Carefully raise the fuel rail and injectors
from the inlet manifold until the injector nozzles are
clear of the manifold. (9) Disconnect each injector wiring connector by
pushing in the wire retaining clip.
(10) Using a small screwdriver, remove the injec-
tor retaining clip and withdraw the injectors from the
fuel rail.
Installation is a reversal of the removal procedure
with attention to the following points:
(1) Check the condition of the injector O ring
seals and renew if necessary. (2) Install the injectors to the fuel rail and secure
with the retaining clips. (3) Connect the wiring connectors to each injec-
tor ensuring that the wire clip is locked in position. (4) Install the injectors to the inlet manifold,
carefully guiding the injectors into place ensuring that
the O ring seals are not damaged.
(5) Install the fuel rail retaining bolts and tighten
to the specified torque. (6) Install the fuel hoses to the fuel rail
and
tighten the hose clamps securely.
(7) Check for fuel leaks as previously described.
To Remove and Install Injector — 1.6 Liter Engine
(1) Depressurize the fuel system as previously
described. (2) Disconnect the negative battery terminal.
(3) Remove the air cleaner assembly. If neces-
sary refer to the heading Air Cleaner Assembly in this
section.
(4) Remove the injector retaining plate screw
and remove the injector retaining plate from the
throttle body assembly. (5) Insert the blade of a screwdriver from the
front of the throttle body assembly under the rim of
the injector in which the retaining plate locates.
Support the screwdriver on a suitable object to act as
a fulcrum. (6) Carefully lever the screwdriver until the
injector can be withdrawn from the throttle body
assembly.
(7) Remove and discard the upper and lower O
ring seals from the injector . If necessary remove the
lower filter screen from the injector.
NOTE: As the injector contains electrical
View of the fuel injector removed from the throttle body assembly. 1.6 liter engine.
Page 141 of 238
Automatic Transaxle 141
(2) Incorrectly adjusted kickdown cable: Check
and adjust or renew the kickdown cable as required.
NOTE: Check and adjust the throttle cable
before adjusting the kickdown cable.
ENGINE WILL NOT START IN P OR N
RANGE OR WILL START IN ANY RANGE
(1) Neutral safety switch faulty: Adjust or renew
the neutral safety switch. (2) Incorrectly adjusted selector cable: Check
and adjust the selector cable as detailed.
2. DESCRIPTION
The automatic transaxle combines a fluid coup-
ling or torque converter with a fully automatic three
speed epicyclic gear system.
The transaxle provides th ree forward ratios and
one reverse. The hydraulic system consists of a single
pump and valv e arrangement.
The final drive or differential and the transaxle
use a common lubricant. The transaxle oil pan and
final drive drain plug will have to be removed to drain
the transaxle completely. Topping up or refilling is
done through the dipstick tube.
The gear selector lever is floor mounted and
connected to the transaxle by an adjustable cable. The
selector quadrant adjacent to the base of the lever is
marked P, R, N, D, 2, 1.
It is necessary for the selector lever to be in P or
N before the engine can be started. When testing or
tuning the engine, the handbrake must be firmly
applied and the selector lever placed in the P position,
otherwise the vehicle could move forward or back-
wards as the engine speed is increased.
For long distance towing the vehicle should be
towed with the front end raised.
It is not possible to start the engine by either
towing or pushing the vehicle.
The transaxle can be removed from the vehicle
without engine removal.
NOTE: As extensive knowledge and equip-
ment is required to overhaul the automatic
transaxle assembly, it is therefore not a
worthwhile repair proposition for the aver-
age person. However if the transaxle must
be overhauled by a specialist or be replaced
with a reconditioned unit, the removal and
installation procedure is fully described at
the end of this section.
3. TRANSAXLE FLUID
Only use the recommended transaxle fluid speci-
fied by the manufacturer when topping up or changing
the fluid in the system.
TO CHECK AND TOP UP
NOTE: The fluid level should be checked
after approximately 5 minutes driving on
the road when the engine has achieved its
normal operating temperature of approxi-
mately 65 deg C.
(1) Place the vehicle on a level floor and open
the engine bonnet.
NOTE: When working on the automatic
transaxle cleanliness is very important. Do
not reuse transaxle fluid and do not allow
foreign matter to enter the filler opening.
(2) Clean around the top of the dipstick to
ensure that no dirt or foreign matter can enter the
dipstick tube.
(3) Place the selector in the P position and
firmly apply the handbrake. (4) Move the selector thro ugh each gear return-
ing it to the P position.
(5) Check the fluid level with the engine running
at idle. Install the dipstick fully into the dipstick tube.
NOTE: If the vehicle has been driven at high
speed, or has been towing a load, or driven
through heavy city traffic in hot weather, a
period of about 30 minutes should be
allowed to permit the transaxle to cool
before checking the fluid level.
(6) Withdraw the dipstick and check the fluid
level reading. The fluid should be at the H mark on
the dipstick. If the fluid is low, stop the engine and
remove the dipstick from the vehicle. Using a funnel,
top up the transaxle with the recommended type of
transaxle fluid through the dipstick tube. (7) If the level is reading too high allow the
engine to cool down for about 30 minutes and recheck
the level as described. If the level is still too high, a
small amount of transaxle fluid may be drained from
the transaxle.
Checking the fluid level on the automatic transaxle
dipstick.
Page 146 of 238
146 Steering — Part 1
STEERING PULLS TO ONE SIDE
(1) Uneven tire wear or pressures: Check the
condition of the tires and inflate to the recommended
pressures.
(2) Incorrect front wheel alignment: Check and
align the front end.
(3) Dragging brakes: Check each wheel for drag-
ging brakes. Overhaul the brakes as necessary. (4) Damaged suspension or crossmember: In-
spect and renew the damaged components. (5) Faulty power steering gear assembly: Re-
move the power steering gear for overhaul.
FRONT WHEEL WOBBLE OR SHIMMY
(1) Uneven tire wear or incorrect tire pressures;
Check the condition of the tires and inflate to the
recommended pressures. (2) Tire or wheel imbalance: Check and balance
as necessary (3) Worn or badly adjusted hub bearings: Check
the condition and adjust the front hub bearings.
(4) Faulty or worn suspension, units: Check and
overhaul or renew as a pair.
NOTE: Check the steering linkage as previ-
ously described. Raise the front of the vehi-
cle and check the adjustment of the hub
bearings by moving the road wheel in and
out at the top and bottom. No movement in
the bearings should be felt. Check the sus-
pension units as outlined in the Front Sus-
pension section.
STEERING ERRATIC OR WANDERING
(1) Incorrect or uneven wheel alignment setting:
Check and adjust th e steering geometry.
(2) Smooth front tires: Check and renew the
tires as necessary.
Checking the steering gear mounting bolts for security.
(3) Steering gear assembly loose on the cross-
member: Inspect for damage and tighten the steering
gear mounting bolts.
(4) Wear in the tie rod ball housing: Renew the
worn t i e rod and ball housing. (5) Wear in the rack and pinion: Remove the
steering gear assembly for overhaul. (6) Loose or incorrectly adjusted hub bearings:
Check and adjust the front hub bearings.
FAILURE OF POWER ASSISTANCE
(1) Loose or broken pump drive belt: Renew or
adjust the pump drive belt.
(2) Low fluid level in the power steering reser-
voir: Check for leakage, repair or renew the faulty
components. Top up the fluid level. (3) Insufficient power steering pump pressure:
Check the delivery pressure, renew the pump if
defective. (4) Faulty power steering gear assembly: Re-
move the power steering gear assembly for overhaul.
Page 150 of 238
150 Steering — Part 2
View of the steering gear and associated components removed from the vehicle.
mark the universal coupling joint in relation to the
steering gear pinion as an aid to installation.
(2) Remove the bolt retaining the universal
coupling joint to the steering gear pinion. (3) Raise the front of the vehicle, support it on
chassis stands at the jack ing points and remove the
front wheels. Refer to the Wheel and Tires section.
(4) Remove the split pins and castellated nuts
from the tie rod end studs and disconnect the tie rod
ends from the steering arms.
NOTE: Disconnect each tie rod end by
placing a suitable dolly or hammer against
one side of the steer ing arm eye and striking
the opposite side with a hammer.
(5) Remove the bolts from the steering gear
mounting brackets. (6) Separate the steering gear pinion from the
universal coupling joint and maneuver the steering
gear from the vehicle. Installation is a reversal of the removal procedure
with attention to the following points:
(1) Ensure that the steering gear mounting
bracket rubbers are in good condition. Renew if
necessary.
(2) Renew the split pins on the tie rod castel-
lated nuts.
(3) Check and if necessary adjust the front wheel
toe in. Refer to the Front Suspension section for the
correct procedure.
TO OVERHAUL
To overhaul the steering gear a range of special
tools is required. If the steering gear has a fault
which requires the removal of the rack or pinion it
is recommended that the necessary repairs be car-
ried out by an authorized dealer.
TO RENEW TIE ROD BALL HOUSINGS
(1) Remove the steering gear from the vehicle as
previously described.
(2) Note or mark the installed position of the
mounting rubbers as an aid to assembly and remove
the rubbers from the steering gear.
(3) Thoroughly clean the exterior of the steering
gear in a suitable cleaning solvent.
(4) Secure the steering gear in a soft jawed vice
and centralize the rack in the steering gear. (5) Loosen both the ti e rod end locknuts and
unscrew the tie rod ends from the tie rods, noting the
number of turns required to do so. Remove the
locknuts from the tie rods. (6) Remove the tie rod rubber boot retaining
clamps, detach the boot s from the steering gear
housing and slide them from the tie rods. Take care to
position a container to catch the oil contained in the
steering gear assembly. (7) Where the tie rod ball housing is retained by
staking, drill the staking away from the rack and t i e
rod using a 4.0 mm drill. Do not drill into the rack
more than is necessary to drill out the staking.
Where the tie rod ball housing is retained by a
lock pin, drill out the lock pin from the ball housing
and tie rod using a 4.0 mm drill. Do not exceed a
drilling depth of 10.0 mm.
Using a 4.0 mm drill to remove the staking from the tie
rod ball housing.
Page 157 of 238
Front Suspension 157
Check the stabilizer bar links for wear and damage.
(3) Incorrect front end alignment: Check and
adjust the alignment as necessary. (4) Defective stabilizer bar mounting rubbers or
worn link ball joints: Renew component as necessary. (5) Weak or broken front coil spring: Renew
both springs as a matching pair. (6) Broken or weak rear coil spring: Renew both
springs as matching pair. (7) Drive shaft bent or distorted: Check and
renew as necessary. (8) Tie rod end worn or damaged: Check and
renew as necessary.
(9) Control arm ball joint worn or damaged:
Check and renew as necessary.
(10) Control arm mounting bolts loose: Tighten
the control arm bolts. (11) Wheel hub bearing worn: Check and renew
as necessary. NOTE: As a quick guide to suspension unit
condition, bounce the front of the vehicle up
and down (one side at a time), the vehicle
should come to rest in a single movement. If
it bounces two or three times before stop-
ping, the suspension unit should be renewed.
If the from of the vehicle is tower on one
side than the other, remove the coil spring
and check its free length against a new
spring. If the spring is found to be unservice-
able it is good practice to install two new
springs as a matching pair. This also applies
to the springs on the rear of the vehicle.
2. DESCRIPTION
The front suspension is an independent type
comprising two Macpherson strut suspension units
mounted vertically on each side of the vehicle. The
lower end of the suspension unit is bolted to the
steering knuckle, which in turn houses the front hub
bearings. The steering knuckle pivots on the control
arm by means of a ball joint.
The control arm pivots at its inner ends on rubber
bushes.
A stabilizer bar is attached to both ends of the
control arms using ball joint links. The stabilizer bar
is attached to the front underbody by brackets and
mounting rubbers.
Each front suspension unit assembly comprises a
tubular shock absorber type suspension unit, sur-
rounded at the upper end by a coil spring. On top of
the coil spring is the upper mounting which attaches
to the underside of the inner mudguard panel. The
piston rod of the suspensi on unit is attached to the
centre of the upper mounting by a rubber mounted
bearing.
When a suspension unit is found to be defective it
is recommended that both suspension units be re-
newed as a pair.
Camber is adjusted by means of a cam on the
upper steering knuckle to suspension unit mounting
bolt.
The kingpin inclination and caster are set in
production and cannot be adjusted. Any variation in
these angles will be caused by worn or damaged
components.
3. STEERING KNUCKLE
Special Equipment Required:
To Renew Wheel Bearing — Press and press plates
and suitable tubes and mandrels
To Check Hub End Float — Dial gauge
TO REMOVE AND INSTAL
(1) Raise the front of the vehicle and support it
on chassis stands. Remove the front wheel.
Checking the control arm bolts for security.
Page 163 of 238
Front Suspension 163
(2) Ensure that the stabilizer bar links are in
good condition. Renew if necessary.
(3) When installing the stabilizer bar ensure that
the links are installed perpendicular to the control arm
with the ball joint socket face parallel to the end of the
stabilizer bar. (4) Ensure that the brackets are installed with
the flat portion facing towards the front of the vehicle.
Tighten the retaining bolts securely.
7. SUSPENSION AND STEERING ANGLES
ADJUSTMENT
NOTE: Extensive knowledge and special-
ised equipment are required to measure and
correct the suspension and steering angles
with the exception of the front wheel toe in.
Therefore, as it is not a viable proposition
for the average person to carry out a com-
plete wheel alignment, the vehicle should be
taken to a wheel alignment specialist.
Prior to carrying out a wheel alignment, a thor-
ough inspection of the steering linkage, front hub
bearings, ball joints and suspension units should be
carried out. Faulty components should be renewed or
repaired as necessary.
The tread of the front ti res should be examined
for excessive or uneven wear as certain conditions of
tire wear are indicative of damaged or worn compo-
nents in the suspension, stee ring linkage and/or wheels
and bearings. Refer to the heading Tire Wear Trouble
Shooting in the Wheels and Tires section. If the tires
are found to be defective, renew them with serviceable
lyres.
TO CHECK AND ADJUST TOE IN/OUT
NOTE: The vehicle s hould be unladen ex-
cept for the normal amount of fuel and with
the tires inflated to the correct pressures.
(1) With the vehicle on a level floor, raise the
front of the vehicle and s upport it on chassis stands.
(2) Spin each front wheel in turn and using a
piece of chalk, mark a line around the periphery of
each tire as near to the centre as possible. (3) Lower the vehicle to the ground and bounce
the front several times to stabilize the suspension. (4) Set the wheels in the straight ahead position.
(5) Mark the centre chalk line on both tires at a
point approximately 200 mm above the floor and
forward of the suspension. (6) Using a tape measure, measure and record
the distance between the two marked points on the
tire centers.
Diagram indicating the front wheel toe in. Refer to
Specifications for the correct difference between
measurement A and B.
(7) Maintaining the wheels in the straight ahead
position, roll the vehicle forward until the marks are
the same distance from the floor but to the rear of the
suspension. (8) Again using the tape measure, measure and
record the distance between the marks on the tires.
(9) The difference between the front and rear
measurement will give the correct toe in/out reading.
If the larger measurement is at the front, the wheels
are in a toe out position. If the reverse is true, the
wheels are in toe in position. Compare the reading
obtained with the figure given in Specifications.
(10) If adjustment of the to e in/out is necessary,
loosen the tie rod locknuts on both sides. (11) Remove the retaining clips from the small
end of the steering rack rubber boots. (12) Turn the tie rods as required until the correct
toe in/out reading is obtained.
NOTE: It is important to turn each tie rod
equally to maintain the central position of
the steering gear. Ensure that the lengths of
the tie rods are the same.
(13) Tighten the tie rod locknuts to the specified
torque without changing the positions of the adjusters.
(14) Install the retaining clips to the small end
of
the steering rack rubber boots, ensuring that the boots
are not twisted.
Page 164 of 238
164
REAR SUSPENSION
SPECIFICATIONS
Type........................... Independent MacPherson strut
Shock absorber.................... Oil filled, non-repairable
Maximum hub bearing end float ................. 0.05 mm
Rear wheel alignment:
Toe out ........................................3 mm ± 2 mm
Camber ............................................. - 1 ° ± 4 5 '
TORQUE WRENCH SETTINGS
Hub retaining nut ......................................... 255 Nm
Suspension unit retaining nuts ....................... 29 Nm
Upper mounting retaining nut ........................ 72 Nm
Suspension unit to knuckle nuts .................. 118 Nm
Control arms to knuckle nut ........................ 118 Nm
Control arms to crossmember nut ............... 118 Nm
Stabiliser bar mounting bracket bolts .......... 108 Nm
Stabiliser bar retaining nut.............................. 83 Nm
Backing plate bolts........................................... 45 Nm
1. REAR SUSPENSION TROUBLE SHOOTING
REAR END NOISE
( 1 ) Defective suspension unit or mounting: Re-
new the faulty components.
(2) Loose or worn control arm bushes or pivot
bolts: Check and tighten or renew the worn compo-
nents. (3) Broken coil spring: Renew the coil spring,
preferably in matching pairs. (4) Worn rear hub bearing: Check and renew the
hub bearing as necessary. (5) Loose or worn stabilizer bar bushes: Check
and tighten or renew the worn components.
NOTE: As a quick guide to suspension unit
condition, bounce the vehicle up and down
(one side at a time) and observe if the vehicle
comes to rest in a single movement If the
vehicle bounces two or three times before
coming to rest the susp ension unit is suspect.
If suspect, remove the suspension unit and
check for fractures and leaks. If the
suspension unit is found to be unserviceable,
it is good practice to install two new
suspension units as a matching pair.
To check the control arm bushes or pivot
bolts, insert a lever between the suspect unit
and its mounting and lever the unit back
and forth checking for excessive movement.
Check the coil springs visually for breaks.
If the spring is found to be unserviceable, it
is good practice to install two new coil
springs as a matching pair.
Rear hub bearing noise can be diagnosed
by raising and supporting the rear of the
vehicle, spinning one wheel at a time and
listening for a rumbling noise.
POOR OR ERRATIC ROAD HOLDING ABILITY
(1) Low or uneven tire pressure: Inflate to the
recommended pressures.
(2) Incorrect rear wheel alignment: Check and
adjust the rear wheel alignment as necessary.
(3) Defective suspension unit: Renew the faulty
suspension unit, preferably in pairs. (4) Loose or broken stabilizer bar: Check and
tighten or renew the faulty components.
Check the stabilizer bar bushes and mounting rubbers
for wear and deterioration.
Page 173 of 238
Brakes 173
Inspect the handbrake cable for chafing or fraying.
(4) Seized handbrake cables: Renew the hand-
brake cables.
NOTE: Raise the vehicle and spin the
wheels one at a time to check for binding. If
the wheels are not binding, have an assistant
apply and release the brakes. Check if the
brakes release immediately. A clogged mas-
ter cylinder port will cause binding on the
two wheels fed by that particular circuit
from the master cylinder. Open the bleeder
valve on one of the o ffending wheels to check
if pressure build up is the cause of the
binding. A seized handbrake cable will usu-
ally cause binding on a rear wheel. Discon-
nect the handbrake cable and check if the
wheel will then turn freely.
LOW SPONGY BRAKE PEDAL
(1) Incorrectly adjusted brake shoes: Check and
adjust the brake shoes.
(2) Insufficient fluid in the system: Check for
leaks, replenish the fluid to the specified level and
bleed the hydraulic system.
(3) Air in the brake hydraulic system: Bleed the
hydraulic system. (4) Master cylinder faulty: Repair or renew as
necessary.
NOTE: A spongy brake pedal in most cases
is caused by air in the hydraulic system. For
air to enter the system one or more of the
sealing rubbers or brake lines must be
sucking in air. Always rectify the cause of
the trouble before bleeding the hydraulic
system. Faulty components usually show up
as fluid leakage.
BRAKES LOCK ON APPLICATION
(1) Gummy linings or brake pads due to oil or
fluid contamination: Renew the linings or brake pads
and rectify the source of contamination. (2) Scored or eccentric brake drum or warped
disc: Check and machine or renew the drum or disc as
necessary.
(3) Incorrect or distorted linings or disc pads:
Check and renew as necessary. (4) Brake servo unit faulty: Repair or renew the
brake servo unit. (5) Broken or stretched brake shoe return
springs: Check and renew th e faulty brake springs.
(6) Faulty brake pressure proportioning valve:
Renew the brake pressure proportioning valve.
NOTE: If this condition arises, remove all
the wheels and check the condition of the
friction material for oil contamination and
excessive wear. Check the shoe return
springs for stretching by comparing their
free length with new sp rings. An eccentric-
brake drum or warped disc will be indicated
by pulsating of the brake pedal when the
brakes are lightly applied.
BRAKE PEDAL PULSATES
(1) Eccentric brake drums or warped disc: Check
and machine or renew the drum or disc as required.
(2) Loose or worn hub bearings: Renew the hub
bearings as necessary.
NOTE: Brake drums or discs that are run-
ning out must be machined. This job is best
entrusted to a brake specialist who will also
be able to determine if a new disc or drum
needs to be installed.
BRAKE FADE
(1) Incorrect shoe adjustment: Check and adjust
the shoe to drum clearance. (2) Eccentric brake drum: Check and machine or
renew the brake drum.
Check the brake hoses for deterioration, chafing and
leaks.