Ford Orion. Manual - part 7

27 Spark plug renewal

1

Note:  Spark plug renewal at this service
interval is only necessary on the HCS and CVH
engines. On the Zetec engine, the
recommended interval for spark plug renewal
is every 30 000 miles or three years.

Spark plug check and renewal

1 It is vital for the correct running, full
performance and proper economy of the
engine that the spark plugs perform with
maximum efficiency. The most important
factor in ensuring this is that the plugs fitted
are appropriate for the engine. The suitable
type is given in the Specifications Section at
the beginning of this Chapter, on the Vehicle
Emissions Control Information (VECI) label
located on the underside of the bonnet (only
on models sold in some areas) or in the
vehicle’s Owner’s Handbook. If the correct
type is used and the engine is in good
condition, the spark plugs should not need
attention between scheduled renewal
intervals. Spark plug cleaning is rarely
necessary, and should not be attempted
unless specialised equipment is available, as
damage can easily be caused to the firing
ends.
2 Spark plug removal and refitting requires a
spark plug socket, with an extension which
can be turned by a ratchet handle or similar.
This socket is lined with a rubber sleeve, to
protect the porcelain insulator of the spark
plug, and to hold the plug while you insert it
into the spark plug hole. You will also need a
set of feeler gauges, to check the spark plug
electrode gap, and a torque wrench to tighten
the new plugs to the specified torque (see
illustration).
3 To remove the spark plugs, first open the
bonnet; the plugs are easily reached at the

top of the engine. Note how the spark plug
(HT) leads are routed and secured by clips,
and on some engines, how they’re positioned
along the channel in the cylinder head cover.
To prevent the possibility of mixing up spark
plug (HT) leads, it is a good idea to try to work
on one spark plug at a time.
4 If the marks on the original-equipment
spark plug (HT) leads cannot be seen, mark
the leads 1 to 4, to correspond to the cylinder
the lead serves (No 1 cylinder is at the timing
belt/chain end of the engine). Pull the leads
from the plugs by gripping the rubber boot
sealing the cylinder head cover opening, not
the lead, otherwise the lead connection may
be fractured.
5 It is advisable to soak up any water in the
spark plug recesses with a rag, and to remove
any dirt from them using a clean brush,
vacuum cleaner or compressed air before
removing the plugs, to prevent any dirt or
water from dropping into the cylinders.
Warning: Wear eye protection when using
compressed air!
6 Unscrew the spark plugs, ensuring that the
socket is kept in alignment with each plug - if
the socket is forcibly moved to either side, the
porcelain top of the plug may be broken off. If
any undue difficulty is encountered when
unscrewing any of the spark plugs, carefully
check the cylinder head threads and tapered
sealing surfaces for signs of wear, excessive
corrosion or damage; if any of these
conditions is found, seek the advice of a Ford
dealer as to the best method of repair.
7 As each plug is removed, examine it as
follows - this will give a good indication of the
condition of the engine. If the insulator nose is
covered with light tan to greyish-brown
deposits, then the mixture is correct, and it is
likely that the engine is in good condition.
8 If the tip and insulator nose are covered
with hard black-looking deposits, then this is
indicative that the mixture is too rich. Should
the plug be black and oily, then it is likely that

the engine is fairly worn, as well as the mixture
being too rich.
9 If the insulator nose of the spark plug is
clean and white, with no deposits, this is
indicative of a weak mixture.
10 If you are renewing the spark plugs,
purchase the new plugs, then check each of
them first for faults such as cracked insulators
or damaged threads. Note also that,
whenever the spark plugs are renewed as a
routine service operation, the spark plug (HT)
leads should be checked as described below.
11 The spark plug electrode gap is of
considerable importance as, if it is too large or
too small, the size of the spark and its
efficiency will be seriously impaired. The gap
should be set to the value given in the Specifi-
cations Section of this Chapter. New plugs
will not necessarily be set to the correct gap,
so they should always be checked before
fitting.
12 The spark plug gap is correct when the
correct-size feeler gauge or wire gauge is a
firm sliding fit between the electrodes (see
illustrations).
13 To adjust the electrode gap, bend open,
or close up, the outer plug electrode until the
correct gap is achieved (see illustration). The
centre electrode should never be bent, as this

Every 20 000 miles  

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27.13  To change the gap, bend the outer
electrode only, and be very careful not to

crack or chip the porcelain insulator

surrounding the centre electrode

27.12B  Spark plug manufacturers

recommend using a wire-type gauge when

checking the gap - if the wire or feeler gauge
does not slide between the electrodes with a

slight drag, adjustment is required

27.12A  Measuring a spark plug gap with a

feeler gauge

27.2  Tools required for changing spark

plugs

1

Every 20 000 miles

may crack the insulation and cause plug
failure, if nothing worse. If the outer electrode
is not exactly over the centre electrode, bend
it gently to align them. Special spark plug gap
adjusting tools are available from motor
accessory shops, or from certain spark plug
manufacturers.
14 Before fitting the spark plugs, check that
the threaded connector sleeves at the top of
the plugs are tight, and that the plug exterior
surfaces and threads are clean. Brown
staining on the porcelain, immediately above
the metal body, is quite normal, and does not
necessarily indicate a “leak” between the
body and insulator.
15 Apply a smear of copper-based grease or
anti-seize compound to the threads of each
plug, and screw them in by hand where
possible. Take extra care to enter the plug
threads correctly, as the cylinder head is of
aluminium alloy.

16 When each spark plug is started correctly
on its threads, screw it down until it just seats

lightly, then tighten it to the specified torque
wrench setting. If a torque wrench is not
available - and this is one case where the use
of a torque wrench is strongly recommended -
tighten each spark plug through no more than
1/4 of a turn (CVH engines) or 1/16 of a turn
(HCS engines) after it seats. HCS engines are
fitted with taper-seat spark plugs, identifiable
by not having a sealing washer, and these in
particular should NEVER be overtightened -
their tapered seats mean they are almost
impossible to remove if abused.
17 Reconnect the spark plug (HT) leads in
their correct order, using a twisting motion on
the boot until it is firmly seated on the end of
the spark plug and on the cylinder head cover.

Spark plug (HT) lead check

18 The spark plug (HT) leads should be
checked whenever the plugs themselves are
renewed. Start by making a visual check of
the leads while the engine is running. In a
darkened garage (make sure there is
ventilation) start the engine and observe each
lead. Be careful not to come into contact with
any moving engine parts. If there is a break in
the lead, you will see arcing or a small spark
at the damaged area.
19 The spark plug (HT) leads should be
inspected one at a time, to prevent mixing up
the firing order, which is essential for proper
engine operation. Each original lead should be
numbered to identify its cylinder. If the
number is illegible, a piece of tape can be
marked with the correct number, and
wrapped around the lead (the leads should be
numbered 1 to 4, with No 1 lead nearest the
timing belt end of the engine). The lead can
then be disconnected.
20 Check inside the boot for corrosion, which
will look like a white crusty powder. Clean this
off as much as possible; if it is excessive, or if
cleaning leaves the metal connector too badly
eroded to be fit for further use, the lead must
be renewed. Push the lead and boot back
onto the end of the spark plug. The boot
should fit tightly onto the end of the plug - if it
doesn’t, remove the lead and use pliers
carefully to crimp the metal connector inside

the boot until the fit is snug.
21 Using a clean rag, wipe the entire length
of the lead to remove built-up dirt and grease.
Once the lead is clean, check for burns,
cracks and other damage. Do not bend the
lead sharply, because the conductor might
break.
22 Disconnect the lead from the ignition coil
by pressing together the plastic retaining
catches and pulling the end fitting off the coil
terminal. Check for corrosion and for a tight
fit. If a meter with the correct measuring range
is available, measure the resistance of the
disconnected lead from its coil connector to
its spark plug connector (see illustration). If
the resistance recorded for any of the leads
exceeds the value specified, all the leads
should be renewed as a set. Refit the lead to
the coil, noting that each coil terminal is
marked with its respective cylinder number,
so that there is no risk of mixing up the leads
and upsetting the firing order.
23 Inspect the remaining spark plug (HT)
leads, ensuring that each is securely fastened
at the ignition coil and spark plug when the
check is complete. If any sign of arcing,
severe connector corrosion, burns, cracks or
other damage is noticed, obtain new spark
plug (HT) leads, renewing them as a set. If
new spark plug leads are to be fitted, remove
and refit them one at a time, to avoid mix-ups
in the firing order.

1•26

Every 20 000 miles

27.22  Measure the resistance of the spark

plug (HT) leads - if any exceeds the

specified maximum value, renew all the

leads as a set

It’s often difficult to insert spark plugs
into their holes without cross-threading
them. To avoid this possibility, fit a
short piece of rubber hose over the end
of the spark plug. The flexible hose
acts as a universal joint, to help align
the plug with the plug hole. Should the
plug begin to cross-thread, the hose
will slip on the spark plug, preventing
thread damage.

Every 30 000 miles or  3 years

28 Coolant renewal

1

Note: If the antifreeze used is Ford’s own, or
of similar quality, the coolant need not be
renewed for the life of the vehicle. If the
vehicle’s history is unknown, if antifreeze of
lesser quality is known to be in the system, or
simply if you prefer to follow conventional
servicing intervals, the coolant should be
changed periodically (typically, every 2 years)
as described here. Refer also to “Antifreeze -
notes on renewal” in this Section.

Warning: Do not allow antifreeze
to come in contact with your skin
or painted surfaces of the
vehicle. Flush contaminated

areas immediately with plenty of water.
Don’t store new coolant, or leave old
coolant lying around, where it’s accessible
to children or pets - they’re attracted by its
sweet smell. Ingestion of even a small
amount of coolant can be fatal! Wipe up
garage-floor and drip-pan spills
immediately. Keep antifreeze containers
covered, and repair cooling system leaks
as soon as they’re noticed.
Warning: Never remove the expansion

tank filler cap when the engine is running,
or has just been switched off, as the
cooling system will be hot, and the
consequent escaping steam and scalding
coolant could cause serious injury.

Coolant draining

Warning: Wait until the engine is
cold before starting this
procedure.

1 To drain the system, first remove the
expansion tank filler cap (see Section 3).
2 If the additional working clearance is
required, raise the front of the vehicle and
support it securely on axle stands.

3 Where fitted, remove the radiator
undershield (eight or nine screws), then place
a large drain tray underneath, and unscrew
the radiator drain plug - you can use a small
coin to do this, as the plug’s slotted for this
purpose (see illustration). Direct as much of
the escaping coolant as possible into the tray.

System flushing

4 With time, the cooling system may
gradually lose its efficiency, as the radiator
core becomes choked with rust, scale
deposits from the water, and other sediment
(refer also to “Antifreeze - notes on renewal”
later in this Section). To minimise this, as well
as using only good-quality antifreeze and
clean soft water, the system should be
flushed as follows whenever any part of it is
disturbed, and/or when the coolant is
renewed.
5 With the coolant drained, refit the drain
plug, and refill the system with fresh water.
Refit the expansion tank filler cap, start the
engine and warm it up to normal operating
temperature, then stop it and (after allowing it
to cool down completely) drain the system
again. Repeat as necessary until only clean
water can be seen to emerge, then refill finally
with the specified coolant mixture as
described below.
6 If only clean, soft water and good-quality
antifreeze (even if not to Ford’s specification)
has been used, and the coolant has been
renewed at the suggested intervals, the above
procedure will be sufficient to keep clean the
system for a considerable length of time. If,
however, the system has been neglected, a
more thorough operation will be required, as
follows.
7 First drain the coolant, then disconnect the
radiator top and bottom hoses. Insert a
garden hose into the top hose, and allow
water to circulate through the radiator until it
runs clean from the bottom outlet.
8 To flush the engine, insert the garden hose
into the thermostat water outlet, and allow
water to circulate until it runs clear from the
bottom hose. If, after a reasonable period, the
water still does not run clear, the radiator
should be flushed with a good proprietary
cleaning agent.
9 In severe cases of contamination, reverse-

flushing of the radiator may be necessary. To
do this, remove the radiator (Chapter 3), invert
it, and insert the garden hose into the bottom
outlet. Continue flushing until clear water runs
from the top hose outlet. A similar procedure
can be used to flush the heater matrix.
10 The use of chemical cleaners should be
necessary only as a last resort. Normally,
regular renewal of the coolant will prevent
excessive contamination of the system.

Coolant filling

11 With the cooling system drained and
flushed, ensure that all disturbed hose unions
are correctly secured, and that the radiator
drain plug is securely tightened. Refit the
radiator undershield, noting that it is located
by three clips at its front edge; tighten the
retaining screws securely. If it was raised,
lower the vehicle to the ground.
12 Prepare a sufficient quantity of the
specified coolant mixture (see below); allow
for a surplus, so as to have a reserve supply
for topping-up.
13 Slowly fill the system through the
expansion tank; since the tank is the highest
point in the system, all the air in the system
should be displaced into the tank by the rising
liquid. Slow pouring reduces the possibility of
air being trapped and forming airlocks.
14 Continue filling until the coolant level
reaches the expansion tank “MAX” level line,
then cover the filler opening to prevent
coolant splashing out.
15 Start the engine and run it at idle speed,
until it has warmed-up to normal operating
temperature and the radiator cooling fan has
cut in; watch the temperature gauge to check
for signs of overheating. If the level in the
expansion tank drops significantly, top-up to
the “MAX” level line, to minimise the amount
of air circulating in the system.
16 Stop the engine, allow it to cool down
completely (overnight, if possible), then
uncover the expansion tank filler opening and
top-up the tank to the “MAX” level line. Refit
the filler cap, tightening it securely, and wash
off any spilt coolant from the engine
compartment and bodywork.
17 After refilling, always check carefully all
components of the system (but especially any
unions disturbed during draining and flushing)
for signs of coolant leaks. Fresh antifreeze has
a searching action, which will rapidly expose
any weak points in the system.
18 Note:  If, after draining and refilling the
system, symptoms of overheating are found
which did not occur previously, then the fault is
almost certainly due to trapped air at some point
in the system, causing an airlock and restricting
the flow of coolant; usually, the air is trapped
because the system was refilled too quickly. In
some cases, airlocks can be released by
tapping or squeezing the various hoses. If the
problem persists, stop the engine and allow it to
cool down completely, before unscrewing the
expansion tank filler cap or disconnecting hoses
to bleed out the trapped air.

Antifreeze mixture

19 If the antifreeze used is not to Ford’s
specification, it should always be renewed at
the suggested intervals (typically, every 2
years). This is necessary not only to maintain
the antifreeze properties, but also to prevent
the corrosion which would otherwise occur as
the corrosion inhibitors become progressively
less effective. Always use an ethylene glycol-
based antifreeze which is suitable for use in
mixed-metal cooling systems.
20 If the antifreeze used is to Ford’s
specification, the levels of protection it affords
are indicated in the Specifications Section of
this Chapter. To give the recommended
standard mixture ratio for this antifreeze, 40%
(by volume) of antifreeze must be mixed with
60% of clean, soft water; if you are using any
other type of antifreeze, follow its
manufacturer’s manuals to achieve the
correct ratio. It is best to make up slightly more
than the system’s specified capacity, so that a
supply is available for subsequent topping-up.
21 Before adding antifreeze, the cooling
system should be completely drained,
preferably flushed, and all hoses checked for
condition and security. As noted earlier, fresh
antifreeze will rapidly find any weaknesses in
the system.
22 After filling with antifreeze, a label should
be attached to the expansion tank, stating the
type and concentration of antifreeze used,
and the date installed. Any subsequent
topping-up should be made with the same
type and concentration of antifreeze. If
topping-up using antifreeze to Ford’s
specification, note that a 50/50 mixture is
permissible, purely for convenience.
23 Do not use engine antifreeze in the
windscreen/tailgate washer system, as it will
damage the vehicle’s paintwork. A
screenwash additive should be added to the
washer system in its maker’s recommended
quantities.

Antifreeze - notes on renewal

24 Ford state that, where antifreeze to Ford
specification ESD-M97B-49-A is used, it will
last the lifetime of the vehicle. This is subject
to it being used in the recommended
concentration, unmixed with any other type of
antifreeze or additive, and topped-up when
necessary using only that antifreeze mixed
50/50 with clean water. If any other type of
antifreeze is added, the lifetime guarantee no
longer applies; to restore the lifetime
protection, the system must be drained and
thoroughly reverse-flushed before fresh
coolant mixture is poured in.
25 If the vehicle’s history (and therefore the
quality of the antifreeze in it) is unknown,
owners who wish to follow Ford’s recommen-
dations are advised to drain and thoroughly
reverse-flush the system  before refilling with
fresh coolant mixture. If the appropriate
quality of antifreeze is used, the coolant can
then be left for the life of the vehicle.

Every 30 000 miles  

1•27

28.3  Use a small coin to unscrew the

radiator drain plug

1

26 If any antifreeze other than Ford’s is to be
used, the coolant must be renewed at regular
intervals to provide an equivalent degree of
protection; the conventional recommendation
is to renew the coolant every two years.
27 The above assumes the use of a mixture
(in exactly the specified concentration) of
clean, soft water and of antifreeze to Ford’s
specification or equivalent. It is also assumed
that the cooling system is maintained in a
scrupulously-clean condition, by ensuring that
only clean coolant is added on topping-up,
and by thorough reverse-flushing whenever
the coolant is drained.

General cooling system checks

28 The engine should be cold for the cooling
system checks, so perform the following
procedure before driving the vehicle, or after it
has been shut off for at least three hours.
29 Remove the expansion tank filler cap (see
Section 3), and clean it thoroughly inside and
out with a rag. Also clean the filler neck on the
expansion tank. The presence of rust or
corrosion in the filler neck indicates that the
coolant should be changed. The coolant
inside the expansion tank should be relatively
clean and transparent. If it is rust- coloured,
drain and flush the system, and refill with a
fresh coolant mixture.
30 Carefully check the radiator hoses and
heater hoses along their entire length; renew
any hose which is cracked, swollen or
deteriorated (see Section 12).
31 Inspect all other cooling system

components (joint faces, etc.) for leaks. A leak
in the cooling system will usually show up as
white- or rust-coloured deposits on the area
adjoining the leak. Where any problems of this
nature are found on system components,
renew the component or gasket with
reference to Chapter 3.
32 Clean the front of the radiator with a soft
brush to remove all insects, leaves, etc,
embedded in the radiator fins. Be careful not
to damage the radiator fins, or cut your fingers
on them.

29 Air cleaner element renewal

1

1 The air cleaner filter element is located in the
air cleaner assembly mounted either on top of
the carburettor or CFi unit, or on the left-hand
side of the engine compartment. Undo the
retaining screws and/or release the clips, and
lift the air cleaner cover (see illustrations).
2 Lift out the element, and wipe out the
housing. Check that no foreign matter is
visible, either in the air inlet or in the air mass
meter, as applicable.
3 If carrying out a routine service, the element
must be renewed regardless of its apparent
condition. Note that the small foam PCV filter
in the rear right-hand corner of the air cleaner
housing must be cleaned whenever the air
filter element is renewed (see Section 30).

4 If you are checking the element for any
other reason, inspect its lower surface; if it is
oily or very dirty, renew the element. If it is
only moderately dusty, it can be re-used after
blowing it clean from the upper to the lower
surface with compressed air.

Warning: Wear eye protection
when using compressed air!
Because it is a pleated-paper
type filter, it cannot be washed or

re-oiled. If it cannot be cleaned satisfac-
torily with compressed air, discard and
renew it.

Caution: Never drive the vehicle
with the air cleaner filter element
removed. Excessive engine wear

could result, and backfiring could even
cause a fire under the bonnet.
5 Refitting is the reverse of the removal
procedure. Ensure that the element and cover
are securely seated, so that unfiltered air
cannot enter the engine.

Air cleaner temperature control
system check (carburettor fuel
system)

6 In order for the engine to operate efficiently,
the temperature of the air entering the inlet
system must be controlled within certain
limits.
7 The air cleaner has two sources of air, one
direct from the outside of the engine
compartment, and the other from a shroud on
the exhaust manifold. On HCS engines, a
wax-controlled thermostatic valve controls a

1•28

Every 30 000 miles

29.1F  . . . then lift off the cover and

withdraw the element

29.1E  . . . and release the clips . . .

29.1D  On EFi and SEFi engines, undo the

air cleaner cover retaining screws . . .

29.1C  . . . then lift off the cover and

withdraw the element

29.1B  . . . and release the clips . . .

29.1A  On carburettor and CFi engines,

undo the air cleaner cover retaining

screws . . .