1997 JAGUAR XJ6 length

again with a dry cloth. Never use alcohol,
petrol, nail polish remover or thinner to clean
leather upholstery.
3After cleaning, regularly treat leather
upholstery with a leather wax. Never use car
wax on leather upholstery.
4In areas where the interior of the vehicle is
subject to bright sunlight, cover leather seats
with a sheet if the vehicle is to be left out for
any length of time.
5 Body repair- minor damage
3
Repair of minor scratches
1If the scratch is superficial and does not
penetrate to the metal of the body, repair is
very simple. Lightly rub the scratched area
with a fine rubbing compound to remove
loose paint and built-up wax. Rinse the area
with clean water.
2Apply touch-up paint to the scratch, using a
small brush. Continue to apply thin layers of
paint until the surface of the paint in the
scratch is level with the surrounding paint.
Allow the new paint at least two weeks to
harden, then blend it into the surrounding
paint by rubbing with a very fine rubbing
compound. Finally, apply a coat of wax to the
scratch area.
3If the scratch has penetrated the paint and
exposed the metal of the body, causing the
metal to rust, a different repair technique is
required. Remove all loose rust from the
bottom of the scratch with a pocket knife,
then apply rust inhibiting paint to prevent the
formation of rust in the future. Using a rubber
or nylon applicator, coat the scratched area
with glaze-type filler. If required, the filler can
be mixed with thinner to provide a very thin
paste, which is ideal for filling narrow
scratches. Before the glaze filler in the scratch
hardens, wrap a piece of smooth cotton cloth
around the tip of a finger. Dip the cloth in
thinner and then quickly wipe it along the
surface of the scratch. This will ensure that
the surface of the filler is slightly hollow. The
scratch can now be painted over as described
earlier in this section.
Repair of dents
4When repairing dents, the first job is to pull
the dent out until the affected area is as close
as possible to its original shape. There is no
point in trying to restore the original shape
completely as the metal in the damaged area
will have stretched on impact and cannot be
restored to its original contours. It is better to
bring the level of the dent up to a point which
is about 1/8-inch below the level of the
surrounding metal. In cases where the dent is
very shallow, it is not worth trying to pull it out
at all.
5If the back side of the dent is accessible, it
can be hammered out gently from behindusing a soft-face hammer. While doing this,
hold a block of wood firmly against the
opposite side of the metal to absorb the
hammer blows and prevent the metal from
being stretched.
6If the dent is in a section of the body which
has double layers, or some other factor makes
it inaccessible from behind, a different
technique is required. Drill several small holes
through the metal inside the damaged area,
particularly in the deeper sections. Screw
long, self-tapping screws into the holes just
enough for them to get a good grip in the
metal. Now the dent can be pulled out by
pulling on the protruding heads of the screws
with locking pliers.
7The next stage of repair is the removal of
paint from the damaged area and from an
inch or so of the surrounding metal. This is
done with a wire brush or sanding disc in a
drill motor, although it can be done just as
effectively by hand with sandpaper. To
complete the preparation for filling, score the
surface of the bare metal with a screwdriver or
the tang of a file, or drill small holes in the
affected area. This will provide a good grip
for the filler material. To complete the repair,
see the subsection on filling and painting later
in this Section.
Repair of rust holes or gashes
8Remove all paint from the affected area and
from an inch or so of the surrounding metal
using a sanding disc or wire brush mounted in
a drill motor. If these are not available, a few
sheets of sandpaper will do the job just as
effectively.
9With the paint removed, you will be able to
determine the severity of the corrosion and
decide whether to replace the whole panel, if
possible, or repair the affected area. New
body panels are not as expensive as most
people think and it is often quicker to refit a
new panel than to repair large areas of rust.
10Remove all trim pieces from the affected
area except those which will act as a guide to
the original shape of the damaged body, such
as headlight shells, etc. Using metal snips or a
hacksaw blade, remove all loose metal and
any other metal that is badly affected by rust.
Hammer the edges of the hole in to create a
slight depression for the filler material.
11Wire brush the affected area to remove
the powdery rust from the surface of the
metal. If the back of the rusted area is
accessible, treat it with rust inhibiting paint.
12Before filling is done, block the hole in
some way. This can be done with sheet metal
riveted or screwed into place, or by stuffing
the hole with wire mesh.
13Once the hole is blocked off, the affected
area can be filled and painted. See the
following subsection on filling and painting.
Filling and painting
14Many types of body fillers are available,
but generally speaking, body repair kits which
contain filler paste and a tube of resinhardener are best for this type of repair work.
A wide, flexible plastic or nylon applicator will
be necessary for imparting a smooth and
contoured finish to the surface of the filler
material. Mix up a small amount of filler on a
clean piece of wood or cardboard (use the
hardener sparingly). Follow the
manufacturer’s instructions on the package,
otherwise the filler will set incorrectly.
15Using the applicator, apply the filler paste
to the prepared area. Draw the applicator
across the surface of the filler to achieve the
desired contour and to level the filler surface.
As soon as a contour that approximates the
original one is achieved, stop working the
paste. If you continue, the paste will begin to
stick to the applicator. Continue to add thin
layers of paste at 20-minute intervals until the
level of the filler is just above the surrounding
metal.
16Once the filler has hardened, the excess
can be removed with a body file. From then
on, progressively finer grades of sandpaper
should be used, starting with a 180-grit paper
and finishing with 600-grit wet-or-dry paper.
Always wrap the sandpaper around a flat
rubber or wooden block, otherwise the
surface of the filler will not be completely flat.
During the sanding of the filler surface, the
wet-or-dry paper should be periodically rinsed
in water. This will ensure that a very smooth
finish is produced in the final stage.
17At this point, the repair area should be
surrounded by a ring of bare metal, which in
turn should be encircled by the finely
feathered edge of good paint. Rinse the repair
area with clean water until all of the dust
produced by the sanding operation is gone.
18Spray the entire area with a light coat of
primer. This will reveal any imperfections in
the surface of the filler. Repair the
imperfections with fresh filler paste or glaze
filler and once more smooth the surface with
sandpaper. Repeat this spray-and-repair
procedure until you are satisfied that the
surface of the filler and the feathered edge of
the paint are perfect. Rinse the area with
clean water and allow it to dry completely.
19The repair area is now ready for painting.
Spray painting must be carried out in a warm,
dry, windless and dust free atmosphere.
These conditions can be created if you have
access to a large indoor work area, but if you
are forced to work in the open, you will have
to pick the day very carefully. If you are
working indoors, dousing the floor in the work
area with water will help settle the dust which
would otherwise be in the air. If the repair area
is confined to one body panel, mask off the
surrounding panels. This will help minimise
the effects of a slight mismatch in paint
colour. Trim pieces such as chrome strips,
door handles, etc., will also need to be
masked off or removed. Use masking tape
and several thickness of newspaper for the
masking operations.
20Before spraying, shake the paint can
thoroughly, then spray a test area until the
11•2 Bodywork and fittings
3261 Jaguar XJ6

3261 Jaguar XJ6
Dimensions and weights . . . . . . . . . . . . . . . . . . .REF•1
Jacking and vehicle support . . . . . . . . . . . . . . . .REF•1
Radio/cassette unit anti-theft system . . . . . . . . .REF•1
Conversion factors . . . . . . . . . . . . . . . . . . . . . . .REF•2
Use of English . . . . . . . . . . . . . . . . . . . . . . . . . . .REF•3
Buying spare parts . . . . . . . . . . . . . . . . . . . . . . . .REF•4
Vehicle identification . . . . . . . . . . . . . . . . . . . . . .REF•4General repair procedures . . . . . . . . . . . . . . . . .REF•5
Tools and working facilities . . . . . . . . . . . . . . . . .REF•6
MOT test checks . . . . . . . . . . . . . . . . . . . . . . . . .REF•8
Fault finding . . . . . . . . . . . . . . . . . . . . . . . . . . . .REF•12
Glossary of technical terms . . . . . . . . . . . . . . . .REF•18
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .REF•22
Dimensions and weights
Note:All figures are approximate, and may vary according to model. Refer to manufacturer’s data for exact figures.
Dimensions
Overall length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4988 mm
Overall width (including mirrors) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2015 mm
Overall height (unladen) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1358 mm
Wheelbase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2870 mm
Weights
Kerb weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1770 kg
Maximum gross vehicle weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2190 kg
Maximum towing weight:
Braked trailer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1500 kg
Unbraked trailer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 750 kg
Maximum axle load:
Front axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1050 kg
Rear axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1170 kg
Maximum roof rack load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 kg
ReferenceREF•1
Radio/cassette unit anti-theft system - precaution
Some models are equipped with an audio
system which includes an anti-theft feature, to
deter thieves. If the power source to the unit is
cut, the anti-theft system will activate. Even if
the power source is immediately reconnected,
the radio/cassette unit will not function untilthe correct security code has been entered.
Therefore if you do not know the correct
security code for the unit, do notdisconnect
the battery negative lead, or remove the
radio/cassette unit from the vehicle.The procedure for reprogramming a unit
that has been disconnected from its power
supply varies from model to model - consult
the handbook supplied with the unit for
specific details or refer to your Jaguar dealer. The jack supplied with the vehicle tool kit
should only be used for changing the
roadwheels - see “Wheel changing”at the
front of this manual. When carrying out any
other kind of work, raise the vehicle using a
hydraulic (or “trolley”) jack, and always
supplement the jack with axle stands
positioned under the vehicle jacking points.
To raise the front of the vehicle, place a
block of wood on the jack head and positionthe jack underneath the centre of the front
crossmember. Lift the vehicle to the required
height and support it on axle stands
positioned underneath the vehicle jacking
points on the sills.
To raise the rear of the vehicle, place a
block of wood on the jack head and position
the jack underneath the centre of the rear
crossmember. Lift the vehicle to the required
height and support it on axle standspositioned underneath the vehicle jacking
points on the sills.
The jack supplied with the vehicle locates in
the jacking points on the sills. Ensure that the
jack head is correctly engaged before
attempting to raise the vehicle.
Neverwork under, around, or near a raised
vehicle, unless it is adequately supported in at
least two places.
Jacking and vehicle support

3261 Jaguar XJ6
REF•2Conversion factors
Length (distance)
Inches (in) x 25.4 = Millimetres (mm) x 0.0394 = Inches (in)
Feet (ft) x 0.305 = Metres (m) x 3.281 = Feet (ft)
Miles x 1.609 = Kilometres (km) x 0.621 = Miles
Volume (capacity)
Cubic inches (cu in; in3) x 16.387 = Cubic centimetres (cc; cm3) x 0.061 = Cubic inches (cu in; in3)
Imperial pints (Imp pt) x 0.568 = Litres (l) x 1.76 = Imperial pints (Imp pt)
Imperial quarts (Imp qt) x 1.137 = Litres (l) x 0.88 = Imperial quarts (Imp qt)
Imperial quarts (Imp qt) x 1.201 = US quarts (US qt) x 0.833 = Imperial quarts (Imp qt)
US quarts (US qt) x 0.946 = Litres (l) x 1.057 = US quarts (US qt)
Imperial gallons (Imp gal) x 4.546 = Litres (l) x 0.22 = Imperial gallons (Imp gal)
Imperial gallons (Imp gal) x 1.201 = US gallons (US gal) x 0.833 = Imperial gallons (Imp gal)
US gallons (US gal) x 3.785 = Litres (l) x 0.264 = US gallons (US gal)
Mass (weight)
Ounces (oz) x 28.35 = Grams (g) x 0.035 = Ounces (oz)
Pounds (lb) x 0.454 = Kilograms (kg) x 2.205 = Pounds (lb)
Force
Ounces-force (ozf; oz) x 0.278 = Newtons (N) x 3.6 = Ounces-force (ozf; oz)
Pounds-force (lbf; lb) x 4.448 = Newtons (N) x 0.225 = Pounds-force (lbf; lb)
Newtons (N) x 0.1 = Kilograms-force (kgf; kg) x 9.81 = Newtons (N)
Pressure
Pounds-force per square inch x 0.070 = Kilograms-force per square x 14.223 = Pounds-force per square inch
(psi; lbf/in2; lb/in2) centimetre (kgf/cm2; kg/cm2) (psi; lbf/in2; lb/in2)
Pounds-force per square inch x 0.068 = Atmospheres (atm) x 14.696 = Pounds-force per square inch
(psi; lbf/in
2; lb/in2)(psi; lbf/in2; lb/in2)
Pounds-force per square inch x 0.069 = Bars x 14.5 = Pounds-force per square inch
(psi; lbf/in
2; lb/in2)(psi; lbf/in2; lb/in2)
Pounds-force per square inch x 6.895 = Kilopascals (kPa) x 0.145 = Pounds-force per square inch
(psi; lbf/in
2; lb/in2)(psi; lbf/in2; lb/in2)
Kilopascals (kPa) x 0.01 = Kilograms-force per square x 98.1 = Kilopascals (kPa)
centimetre (kgf/cm
2; kg/cm2)
Millibar (mbar) x 100 = Pascals (Pa) x 0.01 = Millibar (mbar)
Millibar (mbar) x 0.0145 = Pounds-force per square inch x 68.947 = Millibar (mbar)
(psi; lbf/in
2; lb/in2)
Millibar (mbar) x 0.75 = Millimetres of mercury (mmHg) x 1.333 = Millibar (mbar)
Millibar (mbar) x 0.401 = Inches of water (inH
2O) x 2.491 = Millibar (mbar)
Millimetres of mercury (mmHg) x 0.535 = Inches of water (inH
2O) x 1.868 = Millimetres of mercury (mmHg)
Inches of water (inH
2O) x 0.036 = Pounds-force per square inch x 27.68 = Inches of water (inH2O)
(psi; lbf/in2; lb/in2)
Torque (moment of force)
Pounds-force inches x 1.152 = Kilograms-force centimetre x 0.868 = Pounds-force inches
(lbf in; lb in) (kgf cm; kg cm) (lbf in; lb in)
Pounds-force inches x 0.113 = Newton metres (Nm) x 8.85 = Pounds-force inches
(lbf in; lb in)(lbf in; lb in)
Pounds-force inches x 0.083 = Pounds-force feet (lbf ft; lb ft) x 12 = Pounds-force inches
(lbf in; lb in)(lbf in; lb in)
Pounds-force feet (lbf ft; lb ft) x 0.138 = Kilograms-force metres x 7.233 = Pounds-force feet (lbf ft; lb ft)
(kgf m; kg m)
Pounds-force feet (lbf ft; lb ft) x 1.356 = Newton metres (Nm) x 0.738 = Pounds-force feet (lbf ft; lb ft)
Newton metres (Nm) x 0.102 = Kilograms-force metres x 9.804 = Newton metres (Nm)
(kgf m; kg m)
Power
Horsepower (hp) x 745.7 = Watts (W) x 0.0013 = Horsepower (hp)
Velocity (speed)
Miles per hour (miles/hr; mph) x 1.609 = Kilometres per hour (km/hr; kph) x 0.621 = Miles per hour (miles/hr; mph)
Fuel consumption*
Miles per gallon (mpg) x 0.354 = Kilometres per litre (km/l) x 2.825 = Miles per gallon (mpg)
Temperature
Degrees Fahrenheit = (°C x 1.8) + 32 Degrees Celsius (Degrees Centigrade; °C) = (°F - 32) x 0.56
* It is common practice to convert from miles per gallon (mpg) to litres/100 kilometres (l/100km), where mpg x l/100 km = 282

3261 Jaguar XJ6
MOT test checksREF•11
MExamine the handbrake mechanism,
checking for frayed or broken cables,
excessive corrosion, or wear or insecurity of
the linkage. Check that the mechanism works
on each relevant wheel, and releases fully,
without binding.
MIt is not possible to test brake efficiency
without special equipment, but a road test can
be carried out later to check that the vehicle
pulls up in a straight line.
Fuel and exhaust systems
MInspect the fuel tank (including the filler
cap), fuel pipes, hoses and unions. All
components must be secure and free from
leaks.
MExamine the exhaust system over its entire
length, checking for any damaged, broken or
missing mountings, security of the retaining
clamps and rust or corrosion.
Wheels and tyres
MExamine the sidewalls and tread area of
each tyre in turn. Check for cuts, tears, lumps,
bulges, separation of the tread, and exposure
of the ply or cord due to wear or damage.
Check that the tyre bead is correctly seated
on the wheel rim, that the valve is sound andproperly seated, and that the wheel is not
distorted or damaged.
MCheck that the tyres are of the correct size
for the vehicle, that they are of the same size
and type on each axle, and that the pressures
are correct.
MCheck the tyre tread depth. The legal
minimum at the time of writing is 1.6 mm over
at least three-quarters of the tread width.
Abnormal tread wear may indicate incorrect
front wheel alignment.
Body corrosion
MCheck the condition of the entire vehicle
structure for signs of corrosion in load-bearing
areas. (These include chassis box sections,
side sills, cross-members, pillars, and all
suspension, steering, braking system and
seat belt mountings and anchorages.) Any
corrosion which has seriously reduced the
thickness of a load-bearing area is likely to
cause the vehicle to fail. In this case
professional repairs are likely to be needed.
MDamage or corrosion which causes sharp
or otherwise dangerous edges to be exposed
will also cause the vehicle to fail.
Petrol models
MHave the engine at normal operating
temperature, and make sure that it is in good
tune (ignition system in good order, air filter
element clean, etc).
MBefore any measurements are carried out,
raise the engine speed to around 2500 rpm,
and hold it at this speed for 20 seconds. Allowthe engine speed to return to idle, and watch
for smoke emissions from the exhaust
tailpipe. If the idle speed is obviously much
too high, or if dense blue or clearly-visible
black smoke comes from the tailpipe for more
than 5 seconds, the vehicle will fail. As a rule
of thumb, blue smoke signifies oil being burnt
(engine wear) while black smoke signifies
unburnt fuel (dirty air cleaner element, or other
carburettor or fuel system fault).
MAn exhaust gas analyser capable of
measuring carbon monoxide (CO) and
hydrocarbons (HC) is now needed. If such an
instrument cannot be hired or borrowed, a
local garage may agree to perform the check
for a small fee.
CO emissions (mixture)
MAt the time of writing, the maximum CO
level at idle is 3.5% for vehicles first used after
August 1986 and 4.5% for older vehicles.
From January 1996 a much tighter limit
(around 0.5%) applies to catalyst-equipped
vehicles first used from August 1992. If the
CO level cannot be reduced far enough to
pass the test (and the fuel and ignition
systems are otherwise in good condition) then
the carburettor is badly worn, or there is some
problem in the fuel injection system or
catalytic converter (as applicable).
HC emissionsMWith the CO emissions within limits, HC
emissions must be no more than 1200 ppm
(parts per million). If the vehicle fails this test
at idle, it can be re-tested at around 2000 rpm;
if the HC level is then 1200 ppm or less, this
counts as a pass.
MExcessive HC emissions can be caused by
oil being burnt, but they are more likely to be
due to unburnt fuel.
Diesel models
MThe only emission test applicable to Diesel
engines is the measuring of exhaust smoke
density. The test involves accelerating the
engine several times to its maximum
unloaded speed.
Note: It is of the utmost importance that the
engine timing belt is in good condition before
the test is carried out.
M
Excessive smoke can be caused by a dirty
air cleaner element. Otherwise, professional
advice may be needed to find the cause.
4Checks carried out on
YOUR VEHICLE’S EXHAUST
EMISSION SYSTEM

3261 Jaguar XJ6
Glossary of technical termsREF•19
Catalytic converterA silencer-like device in
the exhaust system which converts certain
pollutants in the exhaust gases into less
harmful substances.
CirclipA ring-shaped clip used to prevent
endwise movement of cylindrical parts and
shafts. An internal circlip is installed in a
groove in a housing; an external circlip fits into
a groove on the outside of a cylindrical piece
such as a shaft.
ClearanceThe amount of space between
two parts. For example, between a piston and
a cylinder, between a bearing and a journal,
etc.
Coil springA spiral of elastic steel found in
various sizes throughout a vehicle, for
example as a springing medium in the
suspension and in the valve train.
CompressionReduction in volume, and
increase in pressure and temperature, of a
gas, caused by squeezing it into a smaller
space.
Compression ratioThe relationship between
cylinder volume when the piston is at top
dead centre and cylinder volume when the
piston is at bottom dead centre.
Constant velocity (CV) jointA type of
universal joint that cancels out vibrations
caused by driving power being transmitted
through an angle.
Core plugA disc or cup-shaped metal device
inserted in a hole in a casting through which
core was removed when the casting was
formed. Also known as a freeze plug or
expansion plug.
CrankcaseThe lower part of the engine
block in which the crankshaft rotates.
CrankshaftThe main rotating member, or
shaft, running the length of the crankcase,
with offset “throws” to which the connecting
rods are attached.
Crocodile clipSee Alligator clipDDiagnostic codeCode numbers obtained by
accessing the diagnostic mode of an engine
management computer. This code can be
used to determine the area in the system
where a malfunction may be located.
Disc brakeA brake design incorporating a
rotating disc onto which brake pads are
squeezed. The resulting friction converts the
energy of a moving vehicle into heat.
Double-overhead cam (DOHC)An engine
that uses two overhead camshafts, usually
one for the intake valves and one for the
exhaust valves.
Drivebelt(s)The belt(s) used to drive
accessories such as the alternator, water
pump, power steering pump, air conditioning
compressor, etc. off the crankshaft pulley.
DriveshaftAny shaft used to transmit
motion. Commonly used when referring to the
axleshafts on a front wheel drive vehicle.
Drum brakeA type of brake using a drum-
shaped metal cylinder attached to the inner
surface of the wheel. When the brake pedal is
pressed, curved brake shoes with friction
linings press against the inside of the drum to
slow or stop the vehicle.
EEGR valveA valve used to introduce exhaust
gases into the intake air stream.
Electronic control unit (ECU)A computer
which controls (for instance) ignition and fuel
injection systems, or an anti-lock braking
system. For more information refer to the
Haynes Automotive Electrical and Electronic
Systems Manual.
Electronic Fuel Injection (EFI)A computer
controlled fuel system that distributes fuel
through an injector located in each intake port
of the engine.
Emergency brakeA braking system,
independent of the main hydraulic system,
that can be used to slow or stop the vehicle if
the primary brakes fail, or to hold the vehicle
stationary even though the brake pedal isn’t
depressed. It usually consists of a hand lever
that actuates either front or rear brakes
mechanically through a series of cables and
linkages. Also known as a handbrake or
parking brake.EndfloatThe amount of lengthwise
movement between two parts. As applied to a
crankshaft, the distance that the crankshaft
can move forward and back in the cylinder
block.
Engine management system (EMS)A
computer controlled system which manages
the fuel injection and the ignition systems in
an integrated fashion.
Exhaust manifoldA part with several
passages through which exhaust gases leave
the engine combustion chambers and enter
the exhaust pipe.
F
Fan clutchA viscous (fluid) drive coupling
device which permits variable engine fan
speeds in relation to engine speeds.
Feeler bladeA thin strip or blade of hardened
steel, ground to an exact thickness, used to
check or measure clearances between parts.
Firing orderThe order in which the engine
cylinders fire, or deliver their power strokes,
beginning with the number one cylinder.
Flywheel A heavy spinning wheel in which
energy is absorbed and stored by means of
momentum. On cars, the flywheel is attached
to the crankshaft to smooth out firing
impulses.
Free playThe amount of travel before any
action takes place. The “looseness” in a
linkage, or an assembly of parts, between the
initial application of force and actual
movement. For example, the distance the
brake pedal moves before the pistons in the
master cylinder are actuated.
FuseAn electrical device which protects a
circuit against accidental overload. The typical
fuse contains a soft piece of metal which is
calibrated to melt at a predetermined current
flow (expressed as amps) and break the
circuit.
Fusible linkA circuit protection device
consisting of a conductor surrounded by
heat-resistant insulation. The conductor is
smaller than the wire it protects, so it acts as
the weakest link in the circuit. Unlike a blown
fuse, a failed fusible link must frequently be
cut from the wire for replacement.Catalytic converter
Crankshaft assembly
Accessory drivebelts
Feeler blade

3261 Jaguar XJ6
REF•20Glossary of technical terms
GGapThe distance the spark must travel in
jumping from the centre electrode to the side
electrode in a spark plug. Also refers to the
spacing between the points in a contact
breaker assembly in a conventional points-
type ignition, or to the distance between the
reluctor or rotor and the pickup coil in an
electronic ignition.
GasketAny thin, soft material - usually cork,
cardboard, asbestos or soft metal - installed
between two metal surfaces to ensure a good
seal. For instance, the cylinder head gasket
seals the joint between the block and the
cylinder head.
GaugeAn instrument panel display used to
monitor engine conditions. A gauge with a
movable pointer on a dial or a fixed scale is an
analogue gauge. A gauge with a numerical
readout is called a digital gauge.
HHalfshaftA rotating shaft that transmits
power from the final drive unit to a drive
wheel, usually when referring to a live rear
axle.
Harmonic balancerA device designed to
reduce torsion or twisting vibration in the
crankshaft. May be incorporated in the
crankshaft pulley. Also known as a vibration
damper.
HoneAn abrasive tool for correcting small
irregularities or differences in diameter in an
engine cylinder, brake cylinder, etc.
Hydraulic tappetA tappet that utilises
hydraulic pressure from the engine’s
lubrication system to maintain zero clearance
(constant contact with both camshaft and
valve stem). Automatically adjusts to variation
in valve stem length. Hydraulic tappets also
reduce valve noise.
IIgnition timingThe moment at which the
spark plug fires, usually expressed in the
number of crankshaft degrees before the
piston reaches the top of its stroke.
Inlet manifoldA tube or housing with
passages through which flows the air-fuel
mixture (carburettor vehicles and vehicles with
throttle body injection) or air only (port fuel-
injected vehicles) to the port openings in the
cylinder head.
JJump startStarting the engine of a vehicle
with a discharged or weak battery by
attaching jump leads from the weak battery to
a charged or helper battery.
LLoad Sensing Proportioning Valve (LSPV)A
brake hydraulic system control valve that
works like a proportioning valve, but also
takes into consideration the amount of weight
carried by the rear axle.
LocknutA nut used to lock an adjustment
nut, or other threaded component, in place.
For example, a locknut is employed to keep
the adjusting nut on the rocker arm in
position.
LockwasherA form of washer designed to
prevent an attaching nut from working loose.
MMacPherson strutA type of front
suspension system devised by Earle
MacPherson at Ford of England. In its original
form, a simple lateral link with the anti-roll bar
creates the lower control arm. A long strut - an
integral coil spring and shock absorber - is
mounted between the body and the steering
knuckle. Many modern so-called MacPherson
strut systems use a conventional lower A-arm
and don’t rely on the anti-roll bar for location.
MultimeterAn electrical test instrument with
the capability to measure voltage, current and
resistance.
NNOxOxides of Nitrogen. A common toxic
pollutant emitted by petrol and diesel engines
at higher temperatures.
OOhmThe unit of electrical resistance. One
volt applied to a resistance of one ohm will
produce a current of one amp.
OhmmeterAn instrument for measuring
electrical resistance.
O-ringA type of sealing ring made of a
special rubber-like material; in use, the O-ring
is compressed into a groove to provide the
sealing action.
Overhead cam (ohc) engineAn engine with
the camshaft(s) located on top of the cylinder
head(s).Overhead valve (ohv) engineAn engine with
the valves located in the cylinder head, but
with the camshaft located in the engine block.
Oxygen sensorA device installed in the
engine exhaust manifold, which senses the
oxygen content in the exhaust and converts
this information into an electric current. Also
called a Lambda sensor.
PPhillips screwA type of screw head having a
cross instead of a slot for a corresponding
type of screwdriver.
PlastigageA thin strip of plastic thread,
available in different sizes, used for measuring
clearances. For example, a strip of Plastigage
is laid across a bearing journal. The parts are
assembled and dismantled; the width of the
crushed strip indicates the clearance between
journal and bearing.
Propeller shaftThe long hollow tube with
universal joints at both ends that carries
power from the transmission to the differential
on front-engined rear wheel drive vehicles.
Proportioning valveA hydraulic control
valve which limits the amount of pressure to
the rear brakes during panic stops to prevent
wheel lock-up.
RRack-and-pinion steeringA steering system
with a pinion gear on the end of the steering
shaft that mates with a rack (think of a geared
wheel opened up and laid flat). When the
steering wheel is turned, the pinion turns,
moving the rack to the left or right. This
movement is transmitted through the track
rods to the steering arms at the wheels.
RadiatorA liquid-to-air heat transfer device
designed to reduce the temperature of the
coolant in an internal combustion engine
cooling system.
RefrigerantAny substance used as a heat
transfer agent in an air-conditioning system.
R-12 has been the principle refrigerant for
many years; recently, however, manufacturers
have begun using R-134a, a non-CFC
substance that is considered less harmful to
the ozone in the upper atmosphere.
Rocker armA lever arm that rocks on a shaft
or pivots on a stud. In an overhead valve
engine, the rocker arm converts the upward
movement of the pushrod into a downward
movement to open a valve.
Adjusting spark plug gap
Plastigage
Gasket