Ford Orion. Manual — part 26

2 Push the crankshaft fully away from the
gauge, and zero it. Next, lever the crankshaft
towards the gauge as far as possible, and
check the reading obtained. The distance that
the crankshaft moved is its endfloat; if it is
greater than specified, check the crankshaft
thrust surfaces for wear. If no wear is evident,
new thrustwashers should correct the endfloat.
3 If no dial gauge is available, feeler gauges
can be used. Gently lever or push the
crankshaft all the way towards the right-hand
end of the engine. Slip feeler gauges between
the crankshaft and the main bearing
incorporating the thrustwashers to determine
the clearance (see illustration).

HCS engine

4 Check that the main bearing caps have
marks to indicate their respective fitted
positions in the block. They also have arrow
marks pointing towards the timing chain cover
end of the engine to indicate correct
orientation

(see illustration).

5 Unscrew the retaining bolts, and remove the
main bearing caps. If the caps are reluctant to
separate from the block face, lightly tap them
free using a plastic- or copper-faced hammer.
If the bearing shells are likely to be used again,
keep them with their bearing caps for
safekeeping. However, unless the engine is
known to be of low mileage, it is
recommended that they be renewed.
6 Lift the crankshaft out from the crankcase,
then extract the upper bearing shells and side
thrustwashers. Keep them with their
respective caps for correct repositioning if
they are to be used again.
7 Remove the crankshaft oil seals from the
timing cover and the rear oil seal housing.

CVH engine

8 Check that each main bearing cap is
numerically marked for position. Each cap
should also have an arrow marking to indicate
its direction of fitting (arrow points to the
timing belt end).
9 Unscrew the retaining bolts, and remove
the main bearing caps. As they are removed,
keep each bearing shell with its cap (in case
they are to used again). Note that the bearing
shells in the main bearing caps are plain (no

groove). It is recommended that the shells be
renewed, unless the engine is known to be of
low mileage.
10 Lift out the crankshaft from the crankcase.
11 Remove each bearing shell in turn from
the crankcase, and keep them in order of
fitting. Note that the upper shell halves are
grooved. Also remove the semi-circular
thrustwasher from each side of the central
main bearing web, and keep them in their
order of fitting.

Zetec engine

12 Check the main bearing caps, to see if they
are marked to indicate their locations (see
illustration)
. They should be numbered
consecutively from the timing belt end of the
engine - if not, mark them with number-
stamping dies or a centre-punch. The caps will
also have an embossed arrow pointing to the
timing belt end of the engine. Noting the
different fasteners (for the oil baffle nuts) used on
caps 2 and 4, slacken the cap bolts a
quarter-turn at a time each, starting with the left-
and right-hand end caps and working toward
the centre, until they can be removed by hand.
13 Gently tap the caps with a soft-faced
hammer, then separate them from the cylinder
block/crankcase. If necessary, use the bolts as
levers to remove the caps. Try not to drop the
bearing shells if they come out with the caps.
14 Carefully lift the crankshaft out of the engine.
15 Remove each bearing shell in turn from
the cylinder block/crankcase, and keep them
in order of fitting.

14 Cylinder block/crankcase -

cleaning and inspection

2

Note: Always check first what replacement
parts are available before planning any
overhaul operation; refer to Section 1. A Ford
dealer, 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.

Cleaning

1 Prior to cleaning, remove all external
components and senders. On the HCS
engine, make sure that the camshaft and
tappets are removed before carrying out
thorough cleaning of the block (see Sec-
tion 11). On the CVH engine, remove the
engine ventilation cap from the recess in the
rear corner of the cylinder block and if still
fitted, undo the retaining screw and withdraw
the engine speed sensor from the bellhousing
face. On the Zetec engine, unbolt the piston-
cooling oil jets or blanking plugs (as
applicable); note that Ford state that the
piston-cooling oil jets (where fitted) must be
renewed whenever the engine is dismantled
for full overhaul (see illustrations).
2 Remove all oil gallery plugs (where fitted).
The plugs are usually very tight - they may

Engine removal and general engine overhaul procedures 2D•21

13.4 Connecting rod big-end bearing cap

and main bearing cap markings

13.3 Checking crankshaft endfloat with a

feeler gauge

14.1A Unbolt blanking plugs (where fitted)

to clean out oilways . . .

13.12 Before unbolting crankshaft main

bearing caps, note arrows pointing to timing

belt end of engine (A), and bearing

numbers (B) consecutive from timing belt end

2D

14.1B . . . but note that piston-cooling oil

jets (where fitted) must be renewed as a

matter of course whenever engine is

overhauled - Zetec engine

have to be drilled out, and the holes re-
tapped. Use new plugs when the engine is
reassembled. Drill a small hole in the centre of
each core plug, and pull them out with a car
bodywork dent puller (see illustration).

Caution: The core plugs (also
known as freeze or soft plugs)
may be difficult or impossible to
retrieve if they are driven into the
block coolant passages.

3 If any of the castings are extremely dirty, all
should be steam-cleaned.
4 After the castings are returned from steam-
cleaning, clean all oil holes and oil galleries
one more time. Flush all internal passages
with warm water until the water runs clear,
then dry thoroughly, and apply a light film of
oil to all machined surfaces, to prevent
rusting. If you have access to compressed air,
use it to speed the drying process, and to
blow out all the oil holes and galleries.

Warning: Wear eye protection
when using compressed air!

5 If the castings are not very dirty, you can do
an adequate cleaning job with hot soapy
water (as hot as you can stand!) and a stiff
brush. Take plenty of time, and do a thorough
job. Regardless of the cleaning method used,
be sure to clean all oil holes and galleries very

thoroughly, and to dry all components
completely; protect the machined surfaces as
described above, to prevent rusting.
6 All threaded holes must be clean and dry,
to ensure accurate torque readings during
reassembly; now is also a good time to clean
and check the threads of all principal bolts -
however, note that some, such as the cylinder
head and flywheel/driveplate bolts, are to be
renewed as a matter of course whenever they
are disturbed. Run the proper-size tap into
each of the holes, to remove rust, corrosion,
thread sealant or sludge, and to restore
damaged threads (see illustration). If
possible, use compressed air to clear the
holes of debris produced by this operation; a
good alternative is to inject aerosol-applied
water-dispersant lubricant into each hole,
using the long spout usually supplied.

Warning: Wear eye protection
when cleaning out these holes in
this way, and be sure to dry out
any excess liquid left in the holes.

7 When all inspection and repair procedures
are complete (see below) and the block is
ready for reassembly, apply suitable sealant
to the new oil gallery plugs, and insert them
into the holes in the block. Tighten them
securely. After coating the sealing surfaces of
the new core plugs with suitable sealant,
install them in the cylinder block/crankcase.

Make sure they are driven in straight and
seated properly, or leakage could result.
Special tools are available for this purpose,
but a large socket with an outside diameter
that will just slip into the core plug, used with
an extension and hammer, will work just as
well.
8 On the Zetec engine, refit the blanking
plugs or (new) piston-cooling oil jets (as
applicable), tightening their Torx screws to the
torque wrench setting specified (see
illustration)
. On all engines, refit all other
external components removed, referring to
the relevant Chapter of this manual for further
details where required. Refit the main bearing
caps, and tighten the bolts finger-tight.
9 If the engine is not going to be reassembled
right away, cover it with a large plastic bag to
keep it clean; protect the machined surfaces
as described above, to prevent rusting.

Inspection

10 Visually check the castings for cracks and
corrosion. Look for stripped threads in the
threaded holes. If there has been any history
of internal coolant leakage, it may be
worthwhile having an engine overhaul
specialist check the cylinder block/crankcase
for cracks with special equipment. If defects
are found, have them repaired, if possible, or
renew the assembly.
11 Check each cylinder bore for scuffing and
scoring.
12 The cylinder bores must be measured
with all the crankshaft main bearing caps
bolted in place (without the crankshaft and
bearing shells), and tightened to the specified
torque wrench settings. Measure the diameter
of each cylinder at the top (just under the
ridge area), centre and bottom of the cylinder
bore, parallel to the crankshaft axis. Next,
measure each cylinder’s diameter at the same
three locations across the crankshaft axis
(see illustrations). Note the measurements
obtained.
13 Measure the piston diameter at right-
angles to the gudgeon pin axis, just above the
bottom of the skirt; again, note the results
(see illustration).

2D•22 Engine removal and general engine overhaul procedures

14.13 Measure the piston skirt diameter at

right-angles to the gudgeon pin axis, just

above the base of the skirt

14.12 Measure the diameter of each

cylinder just under the wear ridge (A), at

the centre (B) and at the bottom (C)

14.8 Do not forget to refit all components -

such as oilway blanking plugs (three of

four arrowed) - tighten fasteners to torque

wrench settings specified

14.6 All bolt holes in the block -

particularly the main bearing cap and head

bolt holes - should be cleaned and

restored with a tap (be sure to remove

debris from the holes after this is done)

14.2 The core plugs should be removed

with a puller - if they’re driven into the

block, they may be impossible to

retrieve

14 If 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).
15 Repeat these procedures for the
remaining pistons and cylinder bores.
16 Compare the results with the Specifica-
tions 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.
17 Worn pistons must be renewed; on some
engines, the 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.
18 If any of the cylinder bores are badly
scuffed 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.
19 If the bores are in reasonably good
condition and not excessively-worn, then it
may only be necessary to renew the piston
rings.
20 If this is the case, 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.
21 Two 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. 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
60º 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 cross-hatch angle -
read and follow any manuals 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.

22 The 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 7
and 8 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.

15 Piston/connecting rod

assemblies - inspection

4

Note: Always check first what replacement
parts are available before planning any
overhaul operation; refer to Section 1. A Ford
dealer, 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.
1 Before the inspection process can be
carried out, the piston/connecting rod
assemblies must be cleaned, and the original
piston rings removed from the pistons. The
rings should have smooth, polished working
surfaces, with no dull or carbon-coated
sections (showing that the ring is not sealing
correctly against the bore wall, so allowing
combustion gases to blow by) and no traces
of wear on their top and bottom surfaces. The
end gaps should be clear of carbon, but not
polished (indicating a too-small end gap), and
all the rings (including the elements of the oil
control ring) should be free to rotate in their
grooves, but without excessive up-and-down
movement. If the rings appear to be in good
condition, they are probably fit for further use;
check the end gaps (in an unworn part of the
bore) as described in Section 19. If any of the
rings appears to be worn or damaged, or has
an end gap significantly different from the
specified value, the usual course of action is
to renew all of them as a set. Note: While it is
usual always to renew piston rings when an
engine is overhauled, this of course assumes
that rings are available separately - if not, it
follows that great care must be taken not to
break or damage any of the rings during the
following procedures, and to ensure that each
ring is marked on removal so that it is refitted
only the original way up, and only to the same
groove.

Engine removal and general engine overhaul procedures 2D•23

14.21 The cylinder hone should leave a

smooth, cross-hatch pattern with the lines

intersecting at approximately a 60º angle

2D

2 Using a piston ring installation tool,
carefully remove the rings from the pistons. If
such a tool is not available, the rings can be
removed by hand, expanding them over the
top of the pistons. The use of two or three old
feeler blades will be helpful in preventing the
rings dropping into empty grooves (see
illustration)
. Be careful not to nick or gouge
the pistons in the process, and mark or label
each ring as it is removed, so that its original
top surface can be identified on reassembly,
and so that it can be returned to its original
groove. Take care also with your hands -
piston rings are sharp!
3 Scrape all traces of carbon from the top of
the piston. A hand-held wire brush or a piece
of fine emery cloth can be used, once the
majority of the deposits have been scraped
away. Do not, under any circumstances, use a
wire brush mounted in a drill motor to remove
deposits from the pistons - the piston material
is soft, and may be eroded away by the wire
brush.
4 Use a piston ring groove-cleaning tool to
remove carbon deposits from the ring
grooves. If a tool isn’t available, but
replacement rings have been found, a piece
broken off the old ring will do the job. Be very
careful to remove only the carbon deposits -
don’t remove any metal, and do not nick or
scratch the sides of the ring grooves. Protect
your fingers - piston rings are sharp!
5 Once the deposits have been removed,
clean the piston/rod assemblies with solvent,
and dry them with compressed air (if
available). Make sure that the oil return holes
in the back sides of the ring grooves, and the
oil hole in the lower end of each rod, are clear.
6 If the pistons and cylinder walls aren’t
damaged or worn excessively - refer to
Section 14 for details of inspection and
measurement procedures - and if the cylinder
block/crankcase is not rebored, new pistons
won’t be necessary. Normal piston wear
appears as even vertical wear on the piston
thrust surfaces, and slight looseness of the
top ring in its groove.
7 Carefully inspect each piston for cracks
around the skirt, at the pin bosses, and at the
ring lands (between the ring grooves).
8 Look for scoring and scuffing on the thrust
faces of the skirt, holes in the piston crown,

and burned areas at the edge of the crown. If
the skirt is scored or scuffed, the engine may
have been suffering from overheating and/or
abnormal combustion, which caused
excessively-high operating temperatures. The
cooling and lubrication systems should be
checked thoroughly. A hole in the piston
crown is an indication that abnormal
combustion (pre-ignition) was occurring.
Burned areas at the edge of the piston crown
are usually evidence of spark knock
(detonation). If any of the above problems
exist, the causes must be corrected, or the
damage will occur again. The causes may
include inlet air leaks, incorrect fuel/air
mixture or incorrect ignition timing.
9 Corrosion of the piston, in the form of small
pits, indicates that coolant is leaking into the
combustion chamber and/or the crankcase.
Again, the cause must be corrected, or the
problem may persist in the rebuilt engine.
10 Check the piston-to-rod clearance by
twisting the piston and rod in opposite
directions. Any noticeable play indicates
excessive wear, which must be corrected. The
piston/connecting rod assemblies should be
taken to a Ford dealer or engine recondi-
tioning specialist to have the pistons,
gudgeon pins and rods checked, and new
components fitted as required.
11 Don’t attempt to separate the pistons
from the connecting rods (even if non-genuine
replacements are found elsewhere). This is a
task for a Ford dealer or similar engine recon-
ditioning specialist, due to the special heating

equipment, press, mandrels and supports
required to do the job. If the piston/
connecting rod assemblies do require this
sort of work, have the connecting rods
checked for bend and twist, since only such
engine repair specialists will have the facilities
for this purpose.
12 Check the connecting rods for cracks and
other damage. Also on CVH engines, check
that the oilway in the base of the connecting
rod is clear by probing with a piece of wire
(see illustration). Temporarily remove the
big-end bearing caps and the old bearing
shells, wipe clean the rod and cap bearing
recesses, and inspect them for nicks, gouges
and scratches. After checking the rods,
replace the old shells, slip the caps into place,
and tighten the bolts finger-tight.

16 Crankshaft - inspection

3

Note: Always check first what replacement
parts are available before planning any
overhaul operation; refer to Section 1. A Ford
dealer, 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.
1 Clean the crankshaft, and dry it with
compressed air if available.

Warning: Wear eye protection
when using compressed air! Be
sure to clean the oil holes with a
pipe cleaner or similar probe.

2 Check the main and crankpin (big-end)
bearing journals for uneven wear, scoring,
pitting and cracking.
3 Rub a penny across each journal several
times (see illustration). If a journal picks up
copper from the penny, it is too rough.
4 Remove all burrs from the crankshaft oil
holes with a stone, file or scraper.
5 Using a micrometer, measure the diameter
of the main bearing and crankpin (big-end)
journals, and compare the results with the
Specifications at the beginning of this Chapter
(see illustration).

2D•24 Engine removal and general engine overhaul procedures

16.5 Measure the diameter of each

crankshaft journal at several points, to

detect taper and out-of-round conditions

16.3 Rubbing a penny lengthwise along

each journal will reveal its condition - if

copper rubs off and is embedded in the

crankshaft, the journals should be reground

15.12 Check that the connecting rod

oilway on CVH engines is clear

15.2 Using feeler gauge blades to remove

piston rings

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Текст

Политика конфиденциальности