1997 JAGUAR XJ6 oil

can be removed and tested using the
procedure below or by a dealer service
department or a repair workshop. Defective
relays must be replaced as a unit.
Testing
1It’s best to refer to the wiring diagram for
the circuit to determine the proper
connections for the relay you’re testing.
However, if you’re not able to determine the
correct connection from the wiring diagrams,
you may be able to determine the test
connections from the information that follows.
2On most relays, two of the terminals are the
relay’s control circuit (they connect to the
relay coil which, when energised, closes the
large contacts to complete the circuit). The
other terminals are the power circuit (they are
connected together within the relay when the
control-circuit coil is energised).
3Relays are sometimes marked as an aid to
help you determine which terminals are the
control circuit and which are the powercircuit (see illustration). As a general rule,
the two thicker wires connected to the relay
are the power circuit; the thinner wires are
the control circuit.
4Remove the relay from the vehicle and check
for continuity between the relay power circuit
terminals. There should be no continuity.5Connect a fused jumper wire between one
of the two control circuit terminals and the
positive battery terminal. Connect another
jumper wire between the other control circuit
terminal and earth. When the connections are
made, the relay should click. On some relays,
polarity may be critical, so, if the relay doesn’t
click, try swapping the jumper wires on the
control circuit terminals.
6With the jumper wires connected, check for
continuity between the power circuit
terminals. Now, there should be continuity.
8If the relay fails any of the above tests,
renew it.
7 Direction indicator/hazard
flasher- general information
Warning: Later model vehicles
are equipped with airbags. To
prevent accidental deployment6.3 Most relays are marked on the outside
to easily identify the control circuit and
power circuits
12•4 Body electrical system
3261 Jaguar XJ6 1990 to 1992 relay location details

11 Fuel, oil and temperature
gauges- check
1
Warning: Later models are
equipped with airbags. To
prevent accidental deployment
of the airbag, which could cause
personal injury or damage to the airbag
system, DO NOT work in the vicinity of the
steering column or instrument panel. The
manufacturer recommends that, on airbag
equipped models, the following procedure
be performed at a dealer service
department or other properly equipped
repair facility because of the special tools
and techniques required to disable the
airbag system.
1All tests below require the ignition switch to
be turned to ON position when testing.
2Check the fuse if the gauge pointer does
not move from the empty, low or cold
positions. If the fuse is OK, locate the
particular sender unit for the circuit you’re
working on (see Chapter 4 for fuel sender unit
location, Chapter 2 for oil sender unit location,
or Chapter 3 for temperature sender unit
location). Connect the sender unit connector
to earth If the pointer goes to the full, high or
hot position renew the sender unit. If the
pointer stays in same position use a jumper
wire to earth the terminal on the back of the
gauge. If the pointer moves with the back of
the gauge earthed the problem lies in the wire
between the gauge and the sender unit. If the
pointer does not moves with the back of the
gauge earthed check for voltage at the other
terminal of the gauge. If voltage is present
renew the gauge.
12 Instrument cluster-
removal and refitting
1
Warning: Later models are
equipped with airbags. To
prevent accidental deployment
of the airbag, which could cause
personal injury or damage to the airbag
system, DO NOT work in the vicinity of the
steering column or instrument panel. The
manufacturer recommends that, on airbag
equipped models, the following procedure
be performed at a dealer service
department or other properly equipped
repair facility because of the special tools
and techniques required to disable the
airbag system.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
1Disconnect the negative battery cable.
2Remove the instrument cluster housing (see
Chapter 11).
3Remove the instrument cluster mounting
screws (see illustration). Separate the
instrument cluster from the cluster housing.
4Refitting is the reverse of removal.
13 Radio and speakers-
removal and refitting
2
Warning: Later models are
equipped with airbags. To
prevent accidental deployment
of the airbag, which could cause
personal injury or damage to the airbag
system, DO NOT work in the vicinity of the
steering column or instrument panel. The
manufacturer recommends that, on airbagequipped models, the following procedure
be performed at a dealer service
department or other properly equipped
repair facility because of the special tools
and techniques required to disable the
airbag system.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
1Disconnect the negative battery cable.
Radio
2Remove the radio trim bezel (Chapter 11).
3Remove the retaining screws (see
illustration), pull the radio/control panel
outward to access the backside and
disconnect the electrical connectors and
aerial lead. Detach the retaining clips and
separate the radio from the control panel.
4Refitting is the reverse of removal.
Speakers
5Remove the door trim panel (Chapter 11).
6Remove the nuts from the speaker
mounting studs (see illustration). Disconnect
the electrical connector and remove the
speaker from the vehicle.
7Refitting is the reverse of removal.
Body electrical system 12•7
12
3261 Jaguar XJ6 12.3 Remove the instrument cluster retaining screws (arrowed)
then separate the instrument cluster from the cluster housing
13.3 Remove the retaining screws (arrowed) and pull the
radio/control panel out enough to unplug the connectors
13.6 Remove the nuts from the retaining
studs (arrowed) to remove the speaker

14 Electric aerial-
removal and refitting
2
Aerial motor assembly
1Remove the aerial mast retaining nut (see
illustration).
2Working in the boot, pry out the plastic
clips securing the driver’s side boot finishing
panels to allow access to the aerial motor
assembly.
3Detach the motor assembly retaining bolts
(see illustration). Disconnect the electrical
connector and earth strap then remove the
aerial motor assembly from the vehicle.
4Refitting is the reverse of removal.
Aerial mast
5Remove the aerial mast retaining nut (see
illustration 14.1).
6With an assistant controlling the ignition
switch, turn the ignition key and the radio to
the ON position. Guide the aerial mast out of
the body as the cable unwinds from the motor
assembly (see illustration). Note the direction
the “teeth” on the aerial cable are facing for
refitting purposes.
7To refit the aerial mast, insert the aerial
cable into the motor assembly with the cable
teeth facing the direction as noted above.
Have your assistant turn the ignition key and
the radio to the ON position. Guide the cableand aerial mast through the opening as the
cable winds back into the motor assembly.
8Refit the aerial mast retaining nut.
15 Windscreen wiper motor-
removal and refitting
2
1Pull the wiper arm nut cover back to access
the wiper arm nuts. Remove the nuts and pull
the wiper arm straight off the shaft (see
illustration).
2Remove the screws and detach the cowl
cover (see Chapter 11).
3Remove the drive spindle nut (see
illustration).
4Remove the retaining bolts located along
the top edge of the wiper motor housing and
detach three retaining clips along the bottom
edge of the wiper motor housing (see
illustration).
5Disconnect the electrical connector and
remove the motor assembly from the vehicle.
6Refitting is the reverse of removal.
16 Heated rear window-
check and repair
2
1The heated rear window consists of a
number of horizontal elements baked onto the
glass surface.2Small breaks in the element can be repaired
without removing the rear window.
Check
3Turn the ignition switch and heated rear
window switches to the ON position.
4When measuring voltage during the next
two tests, wrap a piece of aluminium foil
around the tip of the voltmeter negative probe
and press the foil against the heating element
with your finger (see illustration). Place the
voltmeter positive lead against the heated
window positive terminal.
5Check the voltage at the centre of each
heating element (see illustration).
12•8 Body electrical system
14.1 The aerial mast retaining nut can be
removed with an open end spanner14.3 Remove the retaining bolts (arrowed),
pull the aerial assembly out and unplug the
electrical connectors and aerial lead14.6 With the ignition key and the radio in
the ON position, guide the aerial mast out
of the motor assembly - note the direction
of the “teeth” on the aerial cable
15.1 Lift up the wiper arm nut cover,
remove the nut and pull the wiper arm
straight off the shaft15.3 Use a spanner or socket to remove
the drive spindle retaining nut15.4 Remove the bolts (A) along the
top edge of the housing and detach the
clips (B) along the bottom edge
3261 Jaguar XJ6
16.4 When measuring the voltage at the
heated rear window grid, wrap a piece of
aluminium foil around the negative probe
of the voltmeter and press the foil against
the element with your finger

6If the voltage is 6 volts, the element is okay
(there is no break). If the voltage is 12 volts,
the element is broken between the centre
of the element and the positive end. If the
voltage is 0 volts the element is broken
between the centre of the element and earth.
7To find the break, place the voltmeter
positive lead against the defogger positive
terminal. Place the voltmeter negative lead
with the foil strip against the heating element
at the positive terminal end and slide it toward
the negative terminal end. The point at which
the voltmeter deflects from zero to several
volts is the point at which the heating element
is broken (see illustration).
Repair
8Repair the break in the element using a
repair kit specifically recommended for this
purpose.
9Prior to repairing a break, turn off the system
and allow it to cool off for a few minutes.
10Lightly buff the element area with fine
steel wool, then clean it thoroughly with
rubbing alcohol.
11Use masking tape to mask off the area
being repaired.
12Thoroughly mix the epoxy, following the
instructions provided with the repair kit.
13Apply the epoxy material to the slit in the
masking tape, overlapping the undamaged
area about 3/4-inch on either end (see
illustration).
14Allow the repair to cure for 24 hours before
removing the tape and using the system.
17 Headlights- renewal
1
Warning: Later models are
equipped with halogen gas-filled
headlight bulbs which are underpressure and may shatter if the surface is
damaged or the bulb is dropped. Wear eye
protection and handle the bulbs carefully,
grasping only the base whenever possible.
Do not touch the surface of the bulb with
your fingers because the oil from your skin
could cause it to overheat and fail
prematurely. If you do touch the bulb
surface, clean it with rubbing alcohol.
Sealed beam units
1Remove the radiator grille (see Chapter 11).
2Detach the headlight bezel trim cover (see
illustration).
3Remove the headlight bezel (see
illustrations).
4Remove the screws which secure the
retaining ring and withdraw the ring. Support
the light as this is done (see illustration).
Body electrical system 12•9
12
16.13 Apply masking tape to the inside of
the window at the damaged area, then
brush on the special conductive coating17.2 Remove the screws (arrowed) and
detach the headlight bezel trim cover
17.3a Remove the two retaining screws
at the top and the one in the grille opening
(arrowed)17.3b The retaining screw at the
outside lower corner can be accessed
from under the bumper
3261 Jaguar XJ6 16.5 To determine if a heating element has broken, check the
voltage at the centre of each element. If the voltage is 6-volts, the
element is unbroken; if the voltage is 12-volts, the element is
broken between the centre and the positive end. If there is no
voltage, the element is broken between the centre and earth
16.7 To find the break, place the voltmeter positive lead against
the heated window positive terminal, place the voltmeter negative
lead with the foil strip against the heating element at the positive
terminal end and slide it toward the negative terminal end -
the point at which the voltmeter reading changes abruptly is the
point at which the element is broken

8Adjustment should be made with the
vehicle parked 25 feet from the wall, sitting
level, the petrol tank half-full and no unusually
heavy load in the vehicle.
9Starting with the low beam adjustment,
position the high intensity zone so it is two
inches below the horizontal line and two
inches to the right of the headlight vertical
line. Adjustments are made by turning the
knobs located behind the headlight housings
(see illustration 18.2).
10With the high beams on, the high intensity
zone should be vertically centred with the
exact centre just below the horizontal line.
Note:It may not be possible to position the
headlight aim exactly for both high and low
beams. If a compromise must be made, keep
in mind that the low beams are the most used
and have the greatest effect on safety.
11Have the headlights adjusted by a dealer
service department or service station at the
earliest opportunity.
19 Headlight housing
(1992 to 1994 models)-
removal and refitting
1
Warning: These vehicles are
equipped with halogen gas-filled
headlight bulbs which are under
pressure and may shatter if the
surface is damaged or the bulb is dropped.
Wear eye protection and handle the bulbs
carefully, grasping only the base whenever
possible. Do not touch the surface of the
bulb with your fingers because the oil from
your skin could cause it to overheat and
fail prematurely. If you do touch the bulb
surface, clean it with rubbing alcohol.
1Remove the headlight bulb (Section 17).
2Remove the retaining nuts, detach the
housing and withdraw it from the vehicle (see
illustration).
3Refitting is the reverse of removal.
20 Horn- check and renewal
2
Check
Note:Check the fuses before beginning
electrical diagnosis.
1Disconnect the electrical connector from
the horn.
2To test the horn, connect battery voltage to
the two terminals with a pair of jumper wires.
If the horn doesn’t sound, renew it.
3If the horn does sound, check for voltage at
the terminal when the horn button is
depressed (see illustration). If there’s voltage
at the terminal, check for a bad earth at the
horn.
4If there’s no voltage at the horn, check the
relay (see Section 6). Note that most horn
relays are either the four-terminal or externally
earthed three-terminal type.
5If the relay is OK, check for voltage to the
relay power and control circuits. If either of the
circuits are not receiving voltage, inspect the
wiring between the relay and the fuse panel.
6If both relay circuits are receiving voltage,
depress the horn button and check the circuit
from the relay to the horn button for continuityto earth. If there’s no continuity, check the
circuit for an open. If the circuit is good, renew
the horn button.
7If there’s continuity to earth through the
horn button, check for an open or short in the
circuit from the relay to the horn.Renewal
8Remove the radiator grille inserts (see
Chapter 11).
9Disconnect the electrical connector and
remove the retaining nuts securing the horn
brackets (see illustration).
10Refitting is the reverse of removal.
21 Bulb renewal
1
Front direction indicator/rear
parking and side marker lights
1Remove the lens retaining screws and the
lens (see illustration).
2Push inward and rotate the bulb anti-
clockwise to remove it from the holder.
3Renew the bulb, refit the lamp lens and test
the bulb operation.
Body electrical system 12•11
12
20.9 Disconnect the electrical connector,
remove the retaining nuts (arrowed) - then
detach the horn(s)21.1 The front direction indicator/rear
parking and side marker light bulbs are
accessible after removing the lens screws
3261 Jaguar XJ6 19.2 Remove the headlight housing retaining nuts (arrowed) from
the backside of the radiator support
20.3 Check for power at the horn terminal with the horn button
depressed

3261 Jaguar XJ6
Use of EnglishREF•3
As the main part of this book has been written in the US, it uses the appropriate US component names, phrases, and spelling. Some of these
differ from those used in the UK. Normally, these cause no difficulty, but to make sure, a glossary is printed below. When ordering spare parts,
remember the parts list may use some of these words:
AMERICAN ENGLISH
Aluminum Aluminium
Antenna Aerial
Authorized Authorised
Auto parts stores Motor factors
Axleshaft Halfshaft
Back-up Reverse
Barrel Choke/venturi
Block Chock
Box-end wrench Ring spanner
Bushing Bush
Carburetor Carburettor
Center Centre
Coast Freewheel
Color Colour
Convertible Drop head coupe
Cotter pin Split pin
Counterclockwise Anti-clockwise
Countershaft (of gearbox) Layshaft
Dashboard Facia
Denatured alcohol Methylated spirit
Dome lamp Interior light
Driveaxle Driveshaft
Driveshaft Propeller shaft
Fender Wing/mudguard
Firewall Bulkhead
Flashlight Torch
Float bowl Float chamber
Floor jack Trolley jack
Freeway, turnpike etc Motorway
Freeze plug Core plug
Frozen Seized
Gas tank Petrol tank
Gasoline (gas) Petrol
Gearshift Gearchange
Generator (DC) Dynamo
Ground (electrical) Earth
Header Exhaust manifold
Heat riser Hot spot
High Top gear
Hood (engine cover) Bonnet
Installation Refitting
Intake Inlet
Jackstands Axle stands
Jumper cable Jump lead
Keeper Collet
Kerosene Paraffin
Knock pin Roll pin
Lash Clearance
Lash Free-play
Latch Catch
Latches Locks
License plate Number plate
Light Lamp
Lock (for valve spring retainer) Split cotter (for valve spring cap)
Lopes Hunts
Lug nut/bolt Wheel nut/bolt
Metal chips or debris Swarf
Misses Misfires
AMERICAN ENGLISH
Muffler Silencer
Odor Odour
Oil pan Sump
Open flame Naked flame
Panel wagon/van Van
Parking brake Handbrake
Parking light Sidelight
Pinging Pinking
Piston pin or wrist pin Gudgeon pin
Piston pin or wrist pin Small end, little end
Pitman arm Drop arm
Power brake booster Servo unit
Primary shoe (of brake) Leading shoe (of brake)
Prussian blue Engineer’s blue
Pry Prise (force apart)
Prybar Lever
Prying Levering
Quarter window Quarterlight
Recap Retread
Release cylinder Slave cylinder
Repair shop Garage
Replacement Renewal
Ring gear (of differential) Crownwheel
Rocker panel (beneath doors) Sill panel (beneath doors)
Rod bearing Big-end bearing
Rotor/disk Disc (brake)
Secondary shoe (of brake) Trailing shoe (of brake)
Sedan Saloon
Setscrew, Allen screw Grub screw
Shock absorber, shock Damper
Snap-ring Circlip
Soft top Hood
Spacer Distance piece
Spare tire Spare wheel
Spark plug wires HT leads
Spindle arm Steering arm
Stabilizer or sway bar Anti-roll bar
Station wagon Estate car
Stumbles Hesitates
Tang or lock Tab washer
Throw-out bearing Thrust bearing
Tie-rod or connecting rod (of steering) Trackrod
Tire Tyre
Transmission Gearbox
Troubleshooting Fault finding/diagnosis
Trunk Boot (luggage compartment)
Turn signal Indicator
TV (throttle valve) cable Kickdown cable
Unpublicized Unpublicised
Valve cover Rocker cover
Valve lifter Tappet
Valve lifter or tappet Cam follower or tappet
Vapor Vapour
Vise Vice
Wheel cover Roadwheel trim
Whole drive line Transmission
Windshield Windscreen
Wrench Spanner

3261 Jaguar XJ6
REF•4Buying spare parts
Spare parts are available from many
sources, including maker’s appointed
garages, accessory shops, and motor factors.
To be sure of obtaining the correct parts, it
will sometimes be necessary to quote the
vehicle identification number. If possible, it
can also be useful to take the old parts along
for positive identification. Items such as
starter motors and alternators may be
available under a service exchange scheme -
any parts returned should be clean.
Our advice regarding spare parts is as
follows.
Officially appointed garages
This is the best source of parts which are
peculiar to your car, and which are not
otherwise generally available (eg, badges,
interior trim, certain body panels, etc). It is
also the only place at which you should buy
parts if the vehicle is still under warranty.
Accessory shops
These are very good places to buy
materials and components needed for themaintenance of your car (oil, air and fuel
filters, light bulbs, drivebelts, greases, brake
pads, touch-up paint, etc). Components of
this nature sold by a reputable shop are
usually of the same standard as those used
by the car manufacturer.
Besides components, these shops also sell
tools and general accessories, usually have
convenient opening hours, charge lower
prices, and can often be found close to home.
Some accessory shops have parts counters
where components needed for almost any
repair job can be purchased or ordered.
Motor factors
Good factors will stock all the more
important components which wear out
comparatively quickly, and can sometimes
supply individual components needed for the
overhaul of a larger assembly (eg, brake seals
and hydraulic parts, bearing shells, pistons,
valves). They may also handle work such as
cylinder block reboring, crankshaft regrinding,
etc.
Tyre and exhaust specialists
These outlets may be independent, or
members of a local or national chain. They
frequently offer competitive prices when
compared with a main dealer or local garage,
but it will pay to obtain several quotes before
making a decision. When researching prices,
also ask what “extras” may be added - for
instance fitting a new valve and balancing the
wheel are both commonly charged on top of
the price of a new tyre.
Other sources
Beware of parts or materials obtained from
market stalls, car boot sales or similar outlets.
Such items are not invariably sub-standard,
but there is little chance of compensation if
they do prove unsatisfactory. In the case of
safety-critical components such as brake
pads, there is the risk of financial loss, and
also of an accident causing injury or death.
Second-hand parts or assemblies obtained
from a car breaker can be a good buy in some
circumstances, but this sort of purchase is
best made by the experienced DIY mechanic.
Vehicle identification
Modifications are a continuing and
unpublicised process in vehicle manufacture,
quite apart from major model changes. Spare
parts manuals and lists are compiled upon a
numerical basis, the individual vehicle
identification numbers being essential to
correct identification of the part concerned.
When ordering spare parts, always give as
much information as possible. Quote the car
model, year of manufacture and registration,
chassis and engine numbers as appropriate.
The Vehicle Identification Number (VIN)
plate is attached to the base of the driver’s
door pillar left-hand wing valance and is
visible once the bonnet has been opened. The
vehicle identification (chassis) number is also
stamped onto a plate located inside the
windscreen and may also be stamped onto
the right-hand inner wing panel in the engine
compartment (see illustrations).
The trim code and paint codeare also
stamped onto the VIN plate.
The engine numberis stamped onto the
right-hand side of the cylinder block, next to
the distributor (see illustration).
The automatic transmission numberis
stamped onto a metal label attached to the
left-hand side of the transmission housing,
just above the sump (see illustration).The VIN is stamped on the right inner wing
panel of the engine compartment
The engine identification number is
stamped on the right side of the engine
block just behind the distributorThe transmission identification number is
located on the left side of the transmission
housing just above the sump
The VIN is also present on the left side of
the dashboard

3261 Jaguar XJ6
General repair proceduresREF•5
Whenever servicing, repair or overhaul work
is carried out on the car or its components, it
is necessary to observe the following
procedures and instructions. This will assist in
carrying out the operation efficiently and to a
professional standard of workmanship.
Joint mating faces and gaskets
When separating components at their
mating faces, never insert screwdrivers or
similar implements into the joint between the
faces in order to prise them apart. This can
cause severe damage which results in oil
leaks, coolant leaks, etc upon reassembly.
Separation is usually achieved by tapping
along the joint with a soft-faced hammer in
order to break the seal. However, note that
this method may not be suitable where
dowels are used for component location.
Where a gasket is used between the mating
faces of two components, ensure that it is
renewed on reassembly, and fit it dry unless
otherwise stated in the repair procedure. Make
sure that the mating faces are clean and dry,
with all traces of old gasket removed. When
cleaning a joint face, use a tool which is not
likely to score or damage the face, and remove
any burrs or nicks with an oilstone or fine file.
Make sure that tapped holes are cleaned
with a pipe cleaner, and keep them free of
jointing compound, if this is being used,
unless specifically instructed otherwise.
Ensure that all orifices, channels or pipes
are clear, and blow through them, preferably
using compressed air.
Oil seals
Oil seals can be removed by levering them
out with a wide flat-bladed screwdriver or
similar tool. Alternatively, a number of self-
tapping screws may be screwed into the seal,
and these used as a purchase for pliers or
similar in order to pull the seal free.
Whenever an oil seal is removed from its
working location, either individually or as part
of an assembly, it should be renewed.
The very fine sealing lip of the seal is easily
damaged, and will not seal if the surface it
contacts is not completely clean and free from
scratches, nicks or grooves. If the original
sealing surface of the component cannot be
restored, and the manufacturer has not made
provision for slight relocation of the seal
relative to the sealing surface, the component
should be renewed.
Protect the lips of the seal from any surface
which may damage them in the course of
fitting. Use tape or a conical sleeve where
possible. Lubricate the seal lips with oil before
fitting and, on dual-lipped seals, fill the space
between the lips with grease.
Unless otherwise stated, oil seals must be
fitted with their sealing lips toward the
lubricant to be sealed.
Use a tubular drift or block of wood of the
appropriate size to install the seal and, if the
seal housing is shouldered, drive the seal
down to the shoulder. If the seal housing isunshouldered, the seal should be fitted with
its face flush with the housing top face (unless
otherwise instructed).
Screw threads and fastenings
Seized nuts, bolts and screws are quite a
common occurrence where corrosion has set
in, and the use of penetrating oil or releasing
fluid will often overcome this problem if the
offending item is soaked for a while before
attempting to release it. The use of an impact
driver may also provide a means of releasing
such stubborn fastening devices, when used
in conjunction with the appropriate
screwdriver bit or socket. If none of these
methods works, it may be necessary to resort
to the careful application of heat, or the use of
a hacksaw or nut splitter device.
Studs are usually removed by locking two
nuts together on the threaded part, and then
using a spanner on the lower nut to unscrew
the stud. Studs or bolts which have broken off
below the surface of the component in which
they are mounted can sometimes be removed
using a stud extractor. Always ensure that a
blind tapped hole is completely free from oil,
grease, water or other fluid before installing
the bolt or stud. Failure to do this could cause
the housing to crack due to the hydraulic
action of the bolt or stud as it is screwed in.
When tightening a castellated nut to accept
a split pin, tighten the nut to the specified
torque, where applicable, and then tighten
further to the next split pin hole. Never
slacken the nut to align the split pin hole,
unless stated in the repair procedure.
When checking or retightening a nut or bolt
to a specified torque setting, slacken the nut
or bolt by a quarter of a turn, and then
retighten to the specified setting. However,
this should not be attempted where angular
tightening has been used.
For some screw fastenings, notably
cylinder head bolts or nuts, torque wrench
settings are no longer specified for the latter
stages of tightening, “angle-tightening” being
called up instead. Typically, a fairly low torque
wrench setting will be applied to the
bolts/nuts in the correct sequence, followed
by one or more stages of tightening through
specified angles.
Locknuts, locktabs and washers
Any fastening which will rotate against a
component or housing during tightening
should always have a washer between it and
the relevant component or housing.
Spring or split washers should always be
renewed when they are used to lock a critical
component such as a big-end bearing
retaining bolt or nut. Locktabs which are
folded over to retain a nut or bolt should
always be renewed.
Self-locking nuts can be re-used in non-
critical areas, providing resistance can be felt
when the locking portion passes over the bolt
or stud thread. However, it should be noted
that self-locking stiffnuts tend to lose theireffectiveness after long periods of use, and
should be renewed as a matter of course.
Split pins must always be replaced with
new ones of the correct size for the hole.
When thread-locking compound is found
on the threads of a fastener which is to be re-
used, it should be cleaned off with a wire
brush and solvent, and fresh compound
applied on reassembly.
Special tools
Some repair procedures in this manual
entail the use of special tools such as a press,
two or three-legged pullers, spring
compressors, etc. Wherever possible, suitable
readily-available alternatives to the
manufacturer’s special tools are described,
and are shown in use. In some instances,
where no alternative is possible, it has been
necessary to resort to the use of a
manufacturer’s tool, and this has been done
for reasons of safety as well as the efficient
completion of the repair operation. Unless you
are highly-skilled and have a thorough
understanding of the procedures described,
never attempt to bypass the use of any
special tool when the procedure described
specifies its use. Not only is there a very great
risk of personal injury, but expensive damage
could be caused to the components involved.
Environmental considerations
When disposing of used engine oil, brake
fluid, antifreeze, etc, give due consideration to
any detrimental environmental effects. Do not,
for instance, pour any of the above liquids
down drains into the general sewage system,
or onto the ground to soak away. Many local
council refuse tips provide a facility for waste
oil disposal, as do some garages. If none of
these facilities are available, consult your local
Environmental Health Department, or the
National Rivers Authority, for further advice.
With the universal tightening-up of
legislation regarding the emission of
environmentally-harmful substances from
motor vehicles, most current vehicles have
tamperproof devices fitted to the main
adjustment points of the fuel system. These
devices are primarily designed to prevent
unqualified persons from adjusting the fuel/air
mixture, with the chance of a consequent
increase in toxic emissions. If such devices
are encountered during servicing or overhaul,
they should, wherever possible, be renewed
or refitted in accordance with the vehicle
manufacturer’s requirements or current
legislation.
Note: It is
antisocial and
illegal to dump oil
down the drain.
To find the
location of your
local oil recycling
bank, call this
number free.