1993 FORD MONDEO oil type

Introduction
A selection of good tools is a fundamental
requirement for anyone contemplating the
maintenance and repair of a motor vehicle.
For the owner who does not possess any,
their purchase will prove a considerable
expense, offsetting some of the savings made
by doing-it-yourself. However, provided that
the tools purchased meet the relevant national
safety standards and are of good quality, they
will last for many years and prove an
extremely worthwhile investment.
To help the average owner to decide which
tools are needed to carry out the various tasks
detailed in this manual, we have compiled
three lists of tools under the following
headings: Maintenance and minor repair,
Repair and overhaul, and Special. Newcomers
to practical mechanics should start off with
the Maintenance and minor repairtool kit, and
confine themselves to the simpler jobs around
the vehicle. Then, as confidence and
experience grow, more difficult tasks can be
undertaken, with extra tools being purchased
as, and when, they are needed. In this way, a
Maintenance and minor repairtool kit can be
built up into a Repair and overhaultool kit over
a considerable period of time, without any
major cash outlays. The experienced do-it-
yourselfer will have a tool kit good enough for
most repair and overhaul procedures, and will
add tools from the Specialcategory when it is
felt that the expense is justified by the amount
of use to which these tools will be put.
Maintenance and minor repair
tool kit
The tools given in this list should be
considered as a minimum requirement if
routine maintenance, servicing and minor
repair operations are to be undertaken. We
recommend the purchase of combination
spanners (ring one end, open-ended the
other); although more expensive than open-
ended ones, they do give the advantages of
both types of spanner.
MCombination spanners:
Metric - 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
19, 21, 22, 24 & 26 mm
MAdjustable spanner - 35 mm jaw (approx)
MTransmission drain plug key (Allen type)
MSet of feeler gauges
MSpark plug spanner (with rubber insert)
MSpark plug gap adjustment tool
MBrake adjuster spanner (where applicable)
MBrake bleed nipple spanner
MScrewdrivers:
Flat blade - approx 100 mm long x 6 mm dia
Cross blade - approx 100 mm long x
6 mm dia
MCombination pliers
MHacksaw (junior)
MTyre pump
MTyre pressure gauge
MOil can
MOil filter removal tool
MFine emery cloth
MWire brush (small)
MFunnel (medium size)
Repair and overhaul tool kit
These tools are virtually essential for
anyone undertaking any major repairs to a
motor vehicle, and are additional to those
given in the Maintenance and minor repairlist.
Included in this list is a comprehensive set of
sockets. Although these are expensive, they
will be found invaluable as they are so
versatile - particularly if various drives are
included in the set. We recommend the half-
inch square-drive type, as this can be used
with most proprietary torque wrenches. If you
cannot afford a socket set, even bought
piecemeal, then inexpensive tubular box
spanners are a useful alternative.
The tools in this list will occasionally need to
be supplemented by tools from the Special
list:
MSockets (or box spanners) to cover range in
previous list
MReversible ratchet drive (for use with
sockets) (see illustration)
MExtension piece, 250 mm (for use with
sockets)
MUniversal joint (for use with sockets)
MTorque wrench (for use with sockets)
MSelf-locking grips
MBall pein hammer
MSoft-faced mallet (plastic/aluminium or
rubber)
MScrewdrivers:
Flat blade - long & sturdy, short (chubby),
and narrow (electrician’s) types
Cross blade - Long & sturdy, and short
(chubby) types
MPliers:
Long-nosed
Side cutters (electrician’s)
Circlip (internal and external)
MCold chisel - 25 mm
MScriber
MScraper
MCentre-punch
MPin punch
MHacksaw
MBrake hose clamp
MBrake bleeding kit
MSelection of twist drillsMSteel rule/straight-edge
MAllen keys (inc. splined/Torx type) (see
illustrations)
MSelection of files
MWire brush
MAxle stands
MJack (strong trolley or hydraulic type)
MLight with extension lead
Special tools
The tools in this list are those which are not
used regularly, are expensive to buy, or which
need to be used in accordance with their
manufacturers’ instructions. Unless relatively
difficult mechanical jobs are undertaken
frequently, it will not be economic to buy
many of these tools. Where this is the case,
you could consider clubbing together with
friends (or joining a motorists’ club) to make a
joint purchase, or borrowing the tools against
a deposit from a local garage or tool hire
specialist. It is worth noting that many of the
larger DIY superstores now carry a large range
of special tools for hire at modest rates.
The following list contains only those tools
and instruments freely available to the public,
and not those special tools produced by the
vehicle manufacturer specifically for its dealer
network. You will find occasional references
to these manufacturers’ special tools in the
text of this manual. Generally, an alternative
method of doing the job without the vehicle
manufacturers’ special tool is given. However,
sometimes there is no alternative to using
them. Where this is the case and the relevant
tool cannot be bought or borrowed, you will
have to entrust the work to a franchised
garage.
MValve spring compressor (see illustration)
MValve grinding tool
MPiston ring compressor (see illustration)
MPiston ring removal/installation tool (see
illustration)
MCylinder bore hone (see illustration)
MBalljoint separator
MCoil spring compressors (where applicable)
MTwo/three-legged hub and bearing puller
(see illustration)
REF•1
Sockets and reversible ratchet driveSpline bit set
Tools and Working Facilities
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Buying spare parts
Spare parts are available from many
sources; for example, Ford garages, other
garages and accessory shops, and motor
factors. Our advice regarding spare part
sources is as follows.
Officially-appointed Ford garages- This is
the best source for parts which are peculiar to
your vehicle, and which are not generally
available (eg complete cylinder heads, internal
transmission components, badges, interior
trim etc). It is also the only place at which you
should buy parts if the vehicle is still under
warranty. To be sure of obtaining the correct
parts, it will be necessary to give the storeman
the full Vehicle Identification Number, and if
possible, to take the old parts along for
positive identification. Many parts are
available under a factory exchange scheme -
any parts returned should always be clean. It
obviously makes good sense to go straight to
the specialists on your vehicle for this type of
part, as they are best equipped to supply you.
Other garages and accessory shops- These
are often very good places to buy materials
and components needed for the maintenance
of your vehicle (eg oil filters, spark plugs,
bulbs, drivebelts, oils and greases, touch-up
paint, filler paste, etc). They also sell general
accessories, usually have convenient opening
hours, charge lower prices, and can often be
found not far from home.
Motor factors- Good factors will stock all
the more important components which wear
out comparatively quickly (eg exhaust
systems, brake pads, seals and hydraulic
parts, clutch components, bearing shells,
pistons, valves etc). Motor factors will often
provide new or reconditioned components on
a part-exchange basis - this can save a
considerable amount of money.
Vehicle identification numbers
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 appropriate identification
number or code being essential to correct
identification of the component concerned.
When ordering spare parts, always give asmuch information as possible. Quote the
vehicle model, year of manufacture, Vehicle
Identification Number and engine numbers, as
appropriate.
The vehicle identification plateis located on
the engine compartment front crossmember
(see illustration). In addition to many other
details, it carries the Vehicle Identification
Number, maximum vehicle weight
information, and codes for interior trim and
body colours.
The Vehicle Identification Numberis given
on the vehicle identification plate. It is also
stamped on the engine compartment
bulkhead, behind the air intake plenum
chamber, and into the body, so that it can be
seen through the bottom left-hand corner of
the windscreen (see illustrations).The engine number, consisting of two
letters and five digits, with the three-letter
engine code nearby, is stamped into a flat-
machined surface on the cylinder
block/crankcase’s forward-facing flange,
between the pulse-air filter housing and the
transmission. To read the number without
removing the engine compartment air intake
resonator - see Chapter 4 - it is easiest to
raise and support the front of the vehicle on
axle stands, so that the number can be seen
from underneath (see illustration). If the
number cannot be seen in this location,
possible alternative sites are on a lower flange
on the cylinder block’s forward face,
immediately above the sump mating surface,
or on the left-hand end of the cylinder head,
between the oil filler cap and ignition coil.
REF•5
Vehicle identification plate on engine
compartment front crossmember
Vehicle identification number in body,
visible through bottom left-hand corner of
windscreen
Vehicle identification number on engine
compartment bulkhead
Engine number (arrowed) on front of
cylinder block/crankcase - seen from
beneath vehicle
Spare Parts/Vehicle Identification
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REF•9
Excessive fuel consumption
m mUnsympathetic driving style, or adverse conditions.
m mAir filter element dirty or clogged (Chapter 1).
m mEngine management system fault (Chapters 1, 4, 5 and 6).
m mIgnition timing incorrect (Chapters 5 and 6).
m mTyres under-inflated (Chapter 1).
Fuel leakage and/or fuel odour
m
mDamaged or corroded fuel tank, pipes or connections (Chapter 1).
m mCharcoal canister and/or connecting pipes leaking (Chapter 6).
Excessive noise or fumes from exhaust system
m
mLeaking exhaust system or manifold joints (Chapters 1, 2 Part A,
and 4).
m mLeaking, corroded or damaged silencers or pipe (Chapter 1).
m mBroken mountings, causing body or suspension contact (Chap-
ters 1 and 4).
Fault Finding
3 Fuel and exhaust system
Noisy in neutral with engine running
m mInput shaft bearings worn (noise apparent with clutch pedal
released, but not when depressed) (Chapter 7, Part A).*
m mClutch release bearing worn (noise apparent with clutch pedal
depressed, possibly less when released) (Chapter 8).
Noisy in one particular gear
m mWorn, damaged or chipped gear teeth (Chapter 7, Part A).*
Difficulty engaging gears
m
mClutch fault (Chapter 8).
m mWorn or damaged gear linkage (Chapter 7, Part A).
m mIncorrectly-adjusted gear linkage (Chapter 7, Part A).
m mWorn synchroniser assemblies (Chapter 7, Part A).*
Vibration
m
mLack of oil (Chapter 1).
m mWorn bearings (Chapter 7, Part A).*
Jumps out of gear
m
mWorn or damaged gear linkage (Chapter 7, Part A).
m mIncorrectly-adjusted gear linkage (Chapter 7, Part A).
m mWorn synchroniser assemblies (Chapter 7, Part A).*
m mWorn selector forks (Chapter 7, Part A).*
Lubricant leaks
m
mLeaking differential side gear oil seal (Chapter 7, Part A).
m mLeaking housing joint (Chapter 7, Part A).*
m mLeaking input shaft oil seal (Chapter 7, Part A).*
m mLeaking selector shaft oil seal (Chapter 7, Part A).
m mLeaking speedometer drive pinion O-ring (Chapter 7, Part A).
* Although the corrective action necessary to remedy the symptoms
described is beyond the scope of the home mechanic, the above
information should be helpful in isolating the cause of the condition, so
that the owner can communicate clearly with a professional mechanic.
4 Clutch
5 Manual transmission
Pedal travels to floor - no pressure or very little
resistance
m mBroken clutch cable (Chapter 8).
m mIncorrect clutch adjustment (Chapter 8).
m mBroken clutch release bearing or fork (Chapter 8).
m mBroken diaphragm spring in clutch pressure plate (Chapter 8).
Clutch fails to disengage (unable to select gears)
m
mIncorrect clutch adjustment (Chapter 8).
m mClutch disc sticking on transmission input shaft splines (Chapter 8).
m mClutch disc sticking to flywheel or pressure plate (Chapter 8).
m mFaulty pressure plate assembly (Chapter 8).
m mClutch release mechanism worn or incorrectly assembled (Chapter 8).
Clutch slips (engine speed increases with no
increase in vehicle speed)
m mIncorrect clutch adjustment (Chapter 8).
m mClutch disc linings excessively worn (Chapter 8).m mClutch disc linings contaminated with oil or grease (Chapter 8).
m mFaulty pressure plate or weak diaphragm spring (Chapter 8).
Judder as clutch is engaged
m
mClutch disc linings contaminated with oil or grease (Chapter 8).
m mClutch disc linings excessively worn (Chapter 8).
m mClutch cable sticking or frayed (Chapter 8).
m mFaulty or distorted pressure plate or diaphragm spring (Chapter 8).
m mWorn or loose engine/transmission mountings (Chapter 2, Part A).
m mClutch disc hub or transmission input shaft splines worn (Chap-
ter 8).
Noise when depressing or releasing clutch pedal
m mWorn clutch release bearing (Chapter 8).
m mWorn or dry clutch pedal bushes (Chapter 8).
m mFaulty pressure plate assembly (Chapter 8).
m mPressure plate diaphragm spring broken (Chapter 8).
m mBroken clutch disc cushioning springs (Chapter 8).
Internal coolant leakage
m
mLeaking cylinder head gasket (Chapter 2, Part A).
m mCracked cylinder head or cylinder bore (Chapter 2, Part B).
Corrosion
m
mInfrequent draining and flushing (Chapter 1).
m mIncorrect antifreeze mixture, or inappropriate antifreeze type
(Chapter 1).
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REF•11Fault Finding
9 Suspension and steering systems
Note:Before diagnosing suspension or steering faults, be sure that the trouble is not due to incorrect tyre pressures, mixtures of tyre types, or
binding brakes. Apart from checking the condition of all electrical connections, any faults occurring on the Adaptive Damping System should be
referred to a Ford dealer for diagnosis.
Vehicle pulls to one side
m mDefective tyre (Chapter 1).
m mExcessive wear in suspension or steering components (Chap-
ter 10).
m mIncorrect front wheel alignment (Chapter 10).
m mAccident damage to steering or suspension components (Chap-
ter 10).
Wheel wobble and vibration
m mFront roadwheels out of balance (vibration felt mainly through the
steering wheel) (Chapter 1).
m mRear roadwheels out of balance (vibration felt throughout the
vehicle) (Chapter 1).
m mRoadwheels damaged or distorted (Chapter 1).
m mFaulty or damaged tyre (Chapter 1).
m mWorn steering or suspension joints, bushes or components
(Chapter 10).
m mRoadwheel nuts loose (Chapter 1).
Excessive pitching and/or rolling around corners, or
during braking
m mDefective shock absorbers (Chapter 10).
m mBroken or weak coil spring and/or suspension component (Chap-
ter 10).
m mWorn or damaged anti-roll bar or mountings (Chapter 10).
Wandering or general instability
m
mIncorrect front wheel alignment (Chapter 10).
m mWorn steering or suspension joints, bushes or components
(Chapter 10).
m mRoadwheels out of balance (Chapter 1).
m mFaulty or damaged tyre (Chapter 1).
m mRoadwheel nuts loose (Chapter 1).
m mDefective shock absorbers (Chapter 10).
Excessively-stiff steering
m
mLack of steering gear lubricant (Chapter 10).
m mSeized track-rod end balljoint or suspension balljoint (Chapter 10).
m mBroken or slipping auxiliary drivebelt (Chapter 1).
m mIncorrect front wheel alignment (Chapter 10).
m mSteering rack or column bent or damaged (Chapter 10).
Excessive play in steering
m
mWorn steering column universal joint(s) or flexible coupling
(Chapter 10).
m mWorn steering track-rod end balljoints (Chapter 10).
m mWorn rack-and-pinion steering gear (Chapter 10).
m mWorn steering or suspension joints, bushes or components
(Chapter 10).
Lack of power assistance
m mBroken or slipping auxiliary drivebelt (Chapter 1).
m mIncorrect power steering fluid level (Chapter 1).
m mRestriction in power steering fluid hoses (Chapter 10).
m mFaulty power steering pump (Chapter 10).
m mFaulty rack-and-pinion steering gear (Chapter 10).
Tyre wear excessive
Tyres worn on inside or outside edges
m
mTyres under-inflated (wear on both edges) (Chapter 1).
m mIncorrect camber or castor angles (wear on one edge only)
(Chapter 10).
m mWorn steering or suspension joints, bushes or components
(Chapter 10).
m mExcessively-hard cornering.
m mAccident damage.
Tyre treads exhibit feathered edges
m
mIncorrect toe setting (Chapter 10).
Tyres worn in centre of tread
m
mTyres over-inflated (Chapter 1).
Tyres worn on inside and outside edges
m
mTyres under-inflated (Chapter 1).
Tyres worn unevenly
m
mTyres out of balance (Chapter 1).
m mExcessive wheel or tyre run-out (Chapter 1).
m mWorn shock absorbers (Chapter 10).
m mFaulty tyre (Chapter 1).
Brake pedal feels spongy when depressed
m
mAir in hydraulic system (Chapter 9).
m mDeteriorated flexible rubber brake hoses (Chapter 9).
m mMaster cylinder mounting nuts loose (Chapter 9).
m mFaulty master cylinder (Chapter 9).
Excessive brake pedal effort required to stop
vehicle
m mFaulty vacuum servo unit (Chapter 9).
m mDisconnected, damaged or insecure brake servo vacuum hose
(Chapter 9).
m mPrimary or secondary hydraulic circuit failure (Chapter 9).
m mSeized brake caliper or wheel cylinder piston(s) (Chapter 9).
m mBrake pads or brake shoes incorrectly fitted (Chapter 9).
m mIncorrect grade of brake pads or brake shoes fitted (Chapter 1).
m mBrake pads or brake shoe linings contaminated (Chapter 1).
Judder felt through brake pedal or steering wheel
when braking
m mExcessive run-out or distortion of front discs or rear drums
(Chapter 9).
m mBrake pad or brake shoe linings worn (Chapter 1).
m mBrake caliper or rear brake backplate mounting bolts loose
(Chapter 9).
m mWear in suspension or steering components or mountings (Chapter 10).
Brakes binding
m
mSeized brake caliper or wheel cylinder piston(s) (Chapter 9).
m mFaulty handbrake mechanism (Chapter 9).
m mFaulty master cylinder (Chapter 9).
Rear wheels locking under normal braking
m
mRear brake shoe linings contaminated (Chapter 1).
m mFaulty brake pressure regulator (Chapter 9).
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REF•14Glossary of Technical Terms
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
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REF•15Glossary 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
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