1993 FORD MONDEO tire size

0•10
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. Allow
the engine speed to return to idle, and watchfor 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 or 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
MOT Test Checks
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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.
7As each plug is removed, examine it as
follows - this will give a good indication of the
condition of the engine. If the insulator nose of
the spark plug is clean and white, with no
deposits, this is indicative of a weak mixture.
8If 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.
9If 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.
10If 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.
11The 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
Specifications Section of this Chapter. New
plugs will not necessarily be set to the correct
gap, so they should always be checked
before fitting.
12Special spark plug electrode gap
adjusting tools are available from most motor
accessory shops (see illustration).
13To set the electrode gap, measure the
gap with a feeler gauge, and then bend open,
or closed, the outer plug electrode until the
correct gap is achieved (see illustration). The
centre electrode should never be bent, as this
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.14Before 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.
15On installing the spark plugs, first check
that the cylinder head thread and sealing
surface are as clean as possible; use a clean
rag wrapped around a paintbrush to wipe
clean the sealing surface. 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 - it’s often
difficult to insert spark plugs into their holes
without cross-threading them.
16When each spark plug is started correctly
on its threads, screw it down until it just seats
lightly, then tighten it to the specified torquewrench setting (see illustration). 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 than1/16 of a turn. Do not
exceed the specified torque setting, and
NEVERovertighten these spark plugs - their
tapered seats mean they are almost
impossible to remove if abused.
17Reconnect 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
18The 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.
19The 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.
20Check 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
corroded 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.
21Using a clean rag, wipe the entire length of
1•25
1
Every 30 000 miles
31.12 Spark plug manufacturers
recommend using a wire-type gauge when
checking the gap - if the wire does not
slide between the electrodes with a slight
drag, adjustment is required31.13 To change the gap, bend the outer
electrode only, as indicated by the arrows,
and be very careful not to crack or chip the
porcelain insulator surrounding the centre
electrode31.16 Spark plugs have tapered seats - do
not overtighten them on refitting, or you
will not be able to get them out again
without risking damage to the plugs and
cylinder head
To avoid the possibility of cross-
threading a spark plug, fit a short piece
of rubber hose over the end of the
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.
procarmanuals.com

How to use this Chapter
This Part of Chapter 2 is devoted to
engine/transmission removal and refitting, to
those repair procedures requiring the removal
of the engine/transmission from the vehicle,
and to the overhaul of engine components. It
includes only the Specifications relevant to
those procedures. Refer to Part A for
additional Specifications, if required.
General information
The information ranges from advice
concerning preparation for an overhaul and
the purchase of replacement parts, to detailed
step-by-step procedures covering removal
and installation of internal engine components
and the inspection of parts.
The following Sections have been written
based on the assumption that the engine has
been removed from the vehicle. For
information concerning in-vehicle engine
repair, as well as removal and installation of
the external components necessary for the
overhaul, see Part A of this Chapter and
Section 5 of this Part.
When overhauling this engine, it is essential
to establish first exactly what replacement
parts are available. At the time of writing,
components such as the piston rings are not
available separately from the
piston/connecting rod assemblies; pistons,
gudgeon pins and valve guides are not
available separately, and very few under- or
oversized components are available for
engine reconditioning. In most cases, it would
appear that the easiest and most
economically-sensible course of action is to
replace a worn or damaged engine with an
exchange unit.
It’s not always easy to determine when, or
if, an engine should be completely
overhauled, as a number of factors must be
considered.
High mileage is not necessarily an
indication that an overhaul is needed, while
low mileage doesn’t preclude the need for an
overhaul. Frequency of servicing is probably
the most important consideration. An engine
that’s had regular and frequent oil and filter
changes, as well as other required
maintenance, will most likely give many
thousands of miles of reliable service.
Conversely, a neglected engine may require
an overhaul very early in its life.
Excessive oil consumption is an indication
that piston rings, valve seals and/or valve
guides are in need of attention. Make surethat oil leaks aren’t responsible before
deciding that the rings and/or guides are
worn. Perform a cylinder compression check
(Part A of this Chapter, Section 3) to
determine the extent of the work required.
Loss of power, rough running, knocking or
metallic engine noises, excessive valve train
noise and high fuel consumption rates may
also point to the need for an overhaul,
especially if they’re all present at the same
time. If a full service doesn’t remedy the
situation, major mechanical work is the only
solution.
An engine overhaul involves restoring all
internal parts to the specification of a new
engine. Note:Always check first what
replacement parts are available before
planning any overhaul operation; refer to
Section 1 of this Part. Ford dealers, or a good
engine reconditioning specialist/automotive
parts supplier may be able to suggest
alternatives which will enable you to overcome
the lack of replacement parts.
During an overhaul, it is usual to renew the
piston rings, and to rebore and/or hone the
cylinder bores; where the rebore is done by an
automotive machine shop, new oversize
pistons and rings will also be installed - all
these operations, of course, assume the
availability of suitable replacement parts. The
main and big-end bearings are generally
renewed and, if necessary, the crankshaft
may be reground to restore the journals.
Generally, the valves are serviced as well,
since they’re usually in less-than-perfect
condition at this point. While the engine is
being overhauled, other components, such as
the starter and alternator, can be renewed as
well, or rebuilt, if the necessary parts can be
found. The end result should be an as-new
engine that will give many trouble-free miles.
Note:Critical cooling system components
such as the hoses, drivebelt, thermostat and
water pump MUST be replaced with new
parts when an engine is overhauled. The
radiator should be checked carefully, to
ensure that it isn’t clogged or leaking (see
Chapter 3). Also, as a general rule, the oil
pump should be renewed when an engine is
rebuilt.
Before beginning the engine overhaul, read
through the entire procedure to familiarise
yourself with the scope and requirements of
the job. Overhauling an engine isn’t difficult,
but it is time-consuming. Plan on the vehicle
being off the road for a minimum of two
weeks, especially if parts must be taken to an
automotive machine shop for repair or
reconditioning. Check on availability of parts,
and make sure that any necessary special
tools and equipment are obtained in advance.
Most work can be done with typical hand
tools, although a number of precision
measuring tools are required, for inspecting
parts to determine if they must be replaced.
Often, an automotive machine shop will
handle the inspection of parts, and will offer
advice concerning reconditioning andreplacement. Note:Always wait until the
engine has been completely dismantled, and
all components, especially the cylinder
block/crankcase, have been inspected, before
deciding what service and repair operations
must be performed by an automotive machine
shop. Since the block’s condition will be the
major factor to consider when determining
whether to overhaul the original engine or buy
a rebuilt one, never purchase parts or have
machine work done on other components
until the cylinder block/crankcase has been
thoroughly inspected.As a general rule, time
is the primary cost of an overhaul, so it
doesn’t pay to install worn or sub-standard
parts.
As a final note, to ensure maximum life and
minimum trouble from a rebuilt engine,
everything must be assembled with care, in a
spotlessly-clean environment.
If you’ve decided that an engine must be
removed for overhaul or major repair work,
several preliminary steps should be taken.
Locating a suitable place to work is
extremely important. Adequate work space,
along with storage space for the vehicle, will
be needed. If a workshop or garage isn’t
available, at the very least, a flat, level, clean
work surface made of concrete or asphalt is
required.
Cleaning the engine compartment and
engine/transmission before beginning the
removal procedure will help keep tools clean
and organized.
The engine can only be withdrawn by
removing it complete with the transmission;
the vehicle’s body must be raised and
supported securely, sufficiently high that the
engine/transmission can be unbolted as a
single unit and lowered to the ground; the
engine/transmission unit can then be
withdrawn from under the vehicle and
separated. An engine hoist or A-frame will
therefore be necessary. Make sure the
equipment is rated in excess of the combined
weight of the engine and transmission. Safety
is of primary importance, considering the
potential hazards involved in removing the
engine/transmission from the vehicle.
If this is the first time you have removed an
engine, a helper should ideally be available.
Advice and aid from someone more
experienced would also be helpful. There are
many instances when one person cannot
simultaneously perform all of the operations
required when removing the engine/
transmission from the vehicle.
Plan the operation ahead of time. Arrange for,
or obtain, all of the tools and equipment you’ll
need prior to beginning the job. Some of the
equipment necessary to perform
engine/transmission removal and installation
3 Engine/transmission removal -
methods and precautions
2 Engine overhaul -
general information
1 General information
Engine removal and general engine overhaul procedures 2B•3
2B
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15Measure the piston diameter at right-
angles to the gudgeon pin axis, just above the
bottom of the skirt; again, note the results
(see illustration).
16If it is wished to obtain the piston-to-bore
clearance, measure the bore and piston skirt
as described above, and subtract the skirt
diameter from the bore measurement. If the
precision measuring tools shown are not
available, the condition of the pistons and
bores can be assessed, though not quite as
accurately, by using feeler gauges as follows.
Select a feeler gauge of thickness equal to the
specified piston-to-bore clearance, and slip it
into the cylinder along with the matching
piston. The piston must be positioned exactly
as it normally would be. The feeler gauge
must be between the piston and cylinder on
one of the thrust faces (at right-angles to the
gudgeon pin bore). The piston should slip
through the cylinder (with the feeler gauge in
place) with moderate pressure; if it falls
through or slides through easily, the clearance
is excessive, and a new piston will be
required. If the piston binds at the lower end
of the cylinder, and is loose toward the top,
the cylinder is tapered. If tight spots are
encountered as the piston/feeler gauge is
rotated in the cylinder, the cylinder is out-of-
round (oval).
17Repeat these procedures for the
remaining pistons and cylinder bores.
18Compare the results with the
Specifications at the beginning of this
Chapter; if any measurement is beyond the
dimensions specified for that class (check the
piston crown marking to establish the class of
piston fitted), or if any bore measurement is
significantly different from the others
(indicating that the bore is tapered or oval),
the piston or bore is excessively-worn.
19Worn pistons must be renewed; at the
time of writing, pistons are available as Ford
replacement parts only as part of the
complete piston/connecting rod assembly.
See a Ford dealer or engine reconditioning
specialist for advice.
20If any of the cylinder bores are badlyscuffed or scored, or if they are excessively-
worn, out-of-round or tapered, the usual
course of action would be to have the cylinder
block/crankcase rebored, and to fit new,
oversized, pistons on reassembly. See a Ford
dealer or engine reconditioning specialist for
advice.
21If the bores are in reasonably good
condition and not excessively-worn, then it
may only be necessary to renew the piston
rings.
22If this is the case (and if new rings can be
found), the bores should be honed, to allow
the new rings to bed in correctly and provide
the best possible seal; before honing the
bores, refit the main bearing caps (without the
bearing shells), and tighten the bolts to the
specified torque wrench setting. Note:If you
don’t have the tools, or don’t want to tackle
the honing operation, most engine
reconditioning specialists will do it for a
reasonable fee.
23Two types of cylinder hones are
commonly available - the flex hone or “bottle-
brush” type, and the more traditional
surfacing hone with spring-loaded stones.
Both will do the job and are used with a
power drill, but for the less-experienced
mechanic, the “bottle-brush” hone will
probably be easier to use. You will also need
some paraffin or honing oil, and rags.
Proceed as follows:
(a) Mount the hone in the drill, compress the
stones, and slip it into the first bore (see
illustration). Be sure to wear safety
goggles or a face shield!
(b) Lubricate the bore with plenty of honing
oil, switch on the drill, and move the hone
up and down the bore, at a pace that will
produce a fine cross-hatch pattern on the
cylinder walls. Ideally, the cross-hatch
lines should intersect at approximately a
60° angle (see illustration). Be sure to
use plenty of lubricant, and don’t take off
any more material than is absolutely
necessary to produce the desired finish.
Note:Piston ring manufacturers may
specify a different crosshatch angle - readand follow any instructions included with
the new rings.
(c) Don’t withdraw the hone from the bore
while it’s running. Instead, switch off the
drill, and continue moving the hone up
and down the bore until it comes to a
complete stop, then compress the stones
and withdraw the hone. If you’re using a
“bottle-brush” hone, switch off the drill,
then turn the chuck in the normal
direction of rotation while withdrawing the
hone from the bore.
(d) Wipe the oil out of the bore, and repeat
the procedure for the remaining cylinders.
(e) When all the cylinder bores are honed,
chamfer the top edges of the bores with a
small file, so the rings won’t catch when
the pistons are installed. Be very careful
not to nick the cylinder walls with the end
of the file.
(f) The entire cylinder block/crankcase must
be washed very thoroughly with warm,
soapy water, to remove all traces of the
abrasive grit produced during the honing
operation. Note:The bores can be
considered clean when a lint-free white
cloth - dampened with clean engine oil -
used to wipe them out doesn’t pick up
any more honing residue, which will show
up as grey areas on the cloth. Be sure to
run a brush through all oil holes and
galleries, and flush them with running
water.
(g) When the cylinder block/crankcase is
completely clean, rinse it thoroughly and
dry it, then lightly oil all exposed
machined surfaces, to prevent rusting.
24The cylinder block/crankcase should now
be completely clean and dry, with all
components checked for wear or damage,
and repaired or overhauled as necessary.
Refit as many ancillary components as
possible, for safekeeping (see paragraphs 9
and 10 above). If reassembly is not to start
immediately, cover the block with a large
plastic bag to keep it clean, and protect the
machined surfaces as described above to
prevent rusting.
2B•16 Engine removal and general engine overhaul procedures
11.15 Measure the piston skirt diameter at
right-angles to the gudgeon pin axis, just
above the base of the skirt11.23A A “bottle-brush” hone will produce
better results if you have never honed
cylinders before11.23B The cylinder hone should leave a
smooth, cross-hatch pattern with the lines
intersecting at approximately a 60º angle
procarmanuals.com

to the engine bearings, the acid attacks and
corrodes the bearing material.
7Incorrect shell refitting during engine
assembly will lead to bearing failure as well.
Tight-fitting shells leave insufficient bearing
running clearance, and will result in oil
starvation. Dirt or foreign particles trapped
behind a bearing shell result in high spots on
the bearing, which lead to failure. Do not
touch any shell’s bearing surface with your
fingers during reassembly; there is a risk of
scratching the delicate surface, or of
depositing particles of dirt on it.
1Before reassembly begins, ensure that all
new parts have been obtained, and that all
necessary tools are available. Read through
the entire procedure, to familiarise yourself
with the work involved, and to ensure that all
items necessary for reassembly of the engine
are at hand. In addition to all normal tools and
materials, suitable sealant will be required for
two of the joint faces (Ford recommend
Hylosil 102 for the cylinder block/crankcase-
to-sump/oil pump/oil seal carrier joints, and
Loctite 518 for the camshaft right-hand
bearing caps). In all other cases, provided the
relevant mating surfaces are clean and flat,
new gaskets will be sufficient to ensure joints
are oil-tight. Do notuse any kind of silicone-
based sealant on any part of the fuel system
or inlet manifold, and neveruse exhaust
sealants upstream of the catalytic converter.
2In order to save time and avoid problems,
engine reassembly can be carried out in the
following order:
(a) Crankshaft (Section 17).
(b) Piston/connecting rod assemblies
(Section 18).
(c) Oil pump (Part A of this Chapter, Section
16).
(d) Sump (Part A of this Chapter, Section 15).
(e) Flywheel/driveplate (Part A of this
Chapter, Section 21).
(f) Cylinder head (Part A of this Chapter,
Section 14).(g) Timing belt inner cover, tensioner and
toothed pulleys, and timing belt (Part A of
this Chapter).
(h) Engine external components.
3At this stage, all engine components should
be absolutely clean and dry, with all faults
repaired; they should be laid out (or in
individual containers) on a completely-clean
work surface.
1Before installing new piston rings, check
the end gaps. Lay out each piston set with a
piston/connecting rod assembly, and keep
them together as a matched set from now on.
2Insert the top compression ring into the first
cylinder, and square it up with the cylinder
walls by pushing it in with the top of the piston
(see illustration). The ring should be near the
bottom of the cylinder, at the lower limit of
ring travel.
3To measure the end gap, slip feeler gauges
between the ends of the ring, until a gauge
equal to the gap width is found (see
illustration). The feeler gauge should slide
between the ring ends with a slight amount of
drag. Compare the measurement to the value
given in the Specifications Section of this
Chapter; if the gap is larger or smaller than
specified, double-check to make sure you
have the correct rings before proceeding. If
you are assessing the condition of used rings,
have the cylinder bores checked and
measured by a Ford dealer or similar engine
reconditioning specialist, so that you can be
sure of exactly which component is worn, and
seek advice as to the best course of action to
take.
4If the end gap is still too small, it must be
opened up by careful filing of the ring ends
using a fine file. If it is too large, this is not as
serious, unless the specified limit is exceeded,
in which case very careful checking is
required of the dimensions of all components,
as well as of the new parts.
5Repeat the procedure for each ring that will
be installed in the first cylinder, and for eachring in the remaining cylinders. Remember to
keep rings, pistons and cylinders matched up.
6Refit the piston rings as follows. Where the
original rings are being refitted, use the marks
or notes made on removal, to ensure that
each ring is refitted to its original groove and
the same way up. New rings generally have
their top surfaces identified by markings
(often an indication of size, such as “STD”, or
the word “TOP”) - the rings must be fitted with
such markings uppermost (see illustration).
Note:Always follow the instructions printed
on the ring package or box - different
manufacturers may require different
approaches. Do not mix up the top and
second compression rings, as they usually
have different cross-sections.
7The oil control ring (lowest one on the
piston) is usually installed first. It is composed
of three separate elements. Slip the
spacer/expander into the groove (see
illustration). If an anti-rotation tang is used,
make sure it is inserted into the drilled hole in
the ring groove. Next, install the lower side
rail. Don’t use a piston ring installation tool on
the oil ring side rails, as they may be
damaged. Instead, place one end of the side
rail into the groove between the
spacer/expander and the ring land, hold it
firmly in place, and slide a finger around the
piston while pushing the rail into the groove
16 Piston rings - refitting
15 Engine overhaul -
reassembly sequence
Engine removal and general engine overhaul procedures 2B•19
2B
16.7A Installing the spacer/expander in
the oil control ring groove
16.2 When checking piston ring end gap,
the ring must be square in the cylinder
bore (this is done by pushing the ring down
with the top of a piston, as shown)
16.3 With the ring square in the bore,
measure the end gap with a feeler
gauge16.6 Look for etched markings (“STD” -
indicating a standard-sized ring - shown
here) identifying piston ring top surface
procarmanuals.com

rod’s big-end onto the crankpin. The piston
rings may try to pop out of the ring
compressor just before entering the cylinder
bore, so keep some pressure on the ring
compressor. Work slowly, and if any
resistance is felt as the piston enters the
cylinder, stop immediately. Find out what’s
binding, and fix it before proceeding. Do not,
for any reason, force the piston into the
cylinder - you might break a ring and/or the
piston.
10To check the big-end bearing running
clearance, cut a piece of the appropriate-size
Plastigage slightly shorter than the width of
the connecting rod bearing, and lay it in place
on the No 1 crankpin (big-end) journal, parallel
with the crankshaft centre-line (see illus-
tration 17.6).
11Clean the connecting rod-to-cap mating
surfaces, and refit the big-end bearing cap.
Make sure the etched number on the cap is
on the same side as that on the rod (see
illustration). Tighten the cap bolts evenly -
first use a torque wrench to tighten the bolts
to the specified (first stage) torque setting,
then use an ordinary socket extension bar
and an angle gauge to tighten the bolts
further through the specified (second stage)
angle. Use a thin-wall socket, to avoid
erroneous torque readings that can result if
the socket is wedged between the cap and
nut. If the socket tends to wedge itself
between the nut and the cap, lift up on it
slightly until it no longer contacts the cap.
Don’t rotate the crankshaft at any time during
this operation!
12Unscrew the bolts and detach the cap,
being very careful not to disturb the
Plastigage.
13Compare the width of the crushed
Plastigage to the scale printed on the
Plastigage envelope, to obtain the running
clearance (see illustration 17.10). Compare it
to the Specifications, to make sure the
clearance is correct.
14If the clearance is not as specified, seek
the advice of a Ford dealer or similar engine
reconditioning specialist - if the crankshaft
journals are in good condition (see Sec-
tion 13), it may be possible simply to renew
the shells to achieve the correct clearance. If
this is not possible, the crankshaft must bereground by a specialist, who can also supply
the necessary undersized shells. First though,
make sure that no dirt or oil was trapped
between the bearing shells and the
connecting rod or cap when the clearance
was measured. Also, recheck the crankpin
diameter. If the Plastigage was wider at one
end than the other, the crankpin journal may
be tapered (see Section 13).
15Carefully scrape all traces of the
Plastigage material off the journal and the
bearing surface. Be very careful not to scratch
the bearing - use your fingernail or the edge of
a credit card.
Final piston/connecting rod
refitting
16Make sure the bearing surfaces are
perfectly clean, then apply a uniform layer of
clean molybdenum disulphide-based grease,
engine assembly lubricant, or clean engine oil,
to both of them. You’ll have to push the piston
into the cylinder to expose the bearing surface
of the shell in the connecting rod.
17Slide the connecting rod back into place
on the crankpin (big-end) journal, refit the big-
end bearing cap, and then tighten the bolts in
two stages, as described above.
18Repeat the entire procedure for the
remaining piston/connecting rod assemblies.
19The important points to remember are:
(a) Keep the backs of the bearing shells and
the recesses of the connecting rods and
caps perfectly clean when assembling
them.
(b) Make sure you have the correct
piston/rod assembly for each cylinder -
use the etched cylinder numbers to
identify the front-facing side of both the
rod and its cap.
(c) The arrow on the piston crown must face
the timing belt end of the engine.
(d) Lubricate the cylinder bores with clean
engine oil.
(e) Lubricate the bearing surfaces when
refitting the big-end bearing caps after the
running clearance has been checked.
20After all the piston/connecting rod
assemblies have been properly installed,
rotate the crankshaft a number of times by
hand, to check for any obvious binding.1With the engine refitted in the vehicle,
double-check the engine oil and coolant
levels. Make a final check that everything has
been reconnected, and that there are no tools
or rags left in the engine compartment.
2With the spark plugs removed and the
ignition system disabled by unplugging the
ignition coil’s electrical connector, remove
fuse 14 to disconnect the fuel pump. Turn the
engine on the starter until the oil pressure
warning light goes out.
3Refit the spark plugs, and connect all the
spark plug (HT) leads (Chapter 1). Reconnect
the ignition coil wiring, refit the fuel pump fuse,
then switch on the ignition and listen for the fuel
pump; it will run for a little longer than usual,
due to the lack of pressure in the system.
4Start the engine, noting that this also may
take a little longer than usual, due to the fuel
system components being empty.
5While the engine is idling, check for fuel,
coolant and oil leaks. Don’t be alarmed if
there are some odd smells and smoke from
parts getting hot and burning off oil deposits.
If the hydraulic tappets have been disturbed,
some valve gear noise may be heard at first;
this should disappear as the oil circulates fully
around the engine, and normal pressure is
restored in the tappets.
6Keep the engine idling until hot water is felt
circulating through the top hose, check that it
idles reasonably smoothly and at the usual
speed, then switch it off.
7After a few minutes, recheck the oil and
coolant levels, and top-up as necessary
(Chapter 1).
8If they were tightened as described, there is
no need to re-tighten the cylinder head bolts
once the engine has first run after reassembly
- in fact, Ford state that the bolts must notbe
re-tightened.
9If new components such as pistons, rings
or crankshaft bearings have been fitted, the
engine must be run-in for the first 500 miles
(800 km). Do not operate the engine at full-
throttle, or allow it to labour in any gear during
this period. It is recommended that the oil and
filter be changed at the end of this period.
19 Engine -
initial start-up after overhaul
2B•22 Engine removal and general engine overhaul procedures
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