air condition FORD SIERRA 1993 2.G DOHC Engine Workshop Manual

Note:A hoist and lifting tackle will be
required.
1Disconnect the battery negative lead.
2Remove the bonnet.
3On carburettor models, remove the air
cleaner.
4On fuel injection models, remove the air
inlet hose, plenum chamber, and air cleaner
lid as an assembly.
5Disconnect the breather hose from the
camshaft cover, and unscrew the bolt securing
the hose support bracket to the left-hand side
of the cylinder head (see illustration).
6Drain the cooling system.
7To provide additional working space,
remove the radiator.
8Disconnect the coolant hoses from the
coolant pump housing on the left-hand side of
the engine.
9Disconnect the coolant hoses from the
thermostat housing.
10Disconnect the heater coolant hose from
the inlet manifold.
11Where applicable, release the coolant
hose from the bracket under the carburettor
automatic choke housing.
12On carburettor models, disconnect the
vacuum pipe from the engine management
module.
13Disconnect the brake servo vacuum hose
from the inlet manifold.14On fuel injection models, disconnect the
vacuum pipes from the MAP sensor (located
at the rear right-hand side of the engine
compartment) and, where applicable, from the
air conditioning system.
15On carburettor models, disconnect the
fuel supply and return hoses at the
carburettor, and plug the ends of the hoses to
minimise petrol spillage. Take adequate fire
precautions.
16On fuel injection models, slowly loosen
the fuel feed union at the fuel rail, to relieve
the pressure in the fuel system before
disconnecting the union. Be prepared for
petrol spillage, and take adequate fire
precautions. Disconnect the fuel feed hose,
and disconnect the fuel return hose from the
fuel pressure regulator. Plug the ends of the
hoses to minimise petrol spillage.
17Disconnect the throttle cable and move it
to one side.
18Disconnect the HT lead from the ignition
coil, and unclip it from the timing chain cover.
19Disconnect the wiring from the following
components as applicable, depending on
model:
Alternator.
Starter motor.
Oil pressure warning lamp switch.
Temperature gauge sender.
Cooling fan switch.
Anti-dieselling valve (carburettor models).
Automatic choke heater (carburettor models).
Engine coolant temperature sensor.
Crankshaft speed/position sensor.
Air charge temperature sensor.
Throttle position sensor.
Fuel temperature sensor.
Fuel injectors.
20On models fitted with power steering,
unbolt the power steering pump from its
mounting bracket and move it clear of the
engine. Note that there is no need to
disconnect the fluid hoses, but make sure that
the pump is adequately supported to avoid
straining them.
21On models fitted with air conditioning,
unbolt the air conditioning compressor from
its mounting bracket, and move it clear of the
engine. Do not disconnect the hoses; make
sure that the compressor is adequately
supported to avoid straining them.
22Unscrew and remove the top engine-to-
gearbox bolts which are accessible from theengine compartment. Note the location of the
bolts, and note the positions of the earth strap
and any wiring clips attached to the bolts (see
illustration).
23Unscrew the securing bolt, and
disconnect the earth lead from the rear left-
hand side of the cylinder head.
24Unscrew the nuts securing the engine
mountings to the engine mounting brackets.
25Apply the handbrake, jack up the front of
the vehicle and support it securely on axle
stands (see “Jacking and Vehicle Support”).
26Drain the engine oil into a suitable
container.
27Remove the starter motor.
28Remove the exhaust downpipe.
29Ensure that the steering wheel is
positioned in the straight-ahead position, then
remove the clamp bolt from the lower steering
column clamp, swivel the plate to one side, and
disconnect the lower steering column from the
lower flexible coupling (see illustration).
30Working inside the vehicle, place a wooden
block under the clutch pedal to raise it fully
against its stop, so holding the automatic
adjuster pawl clear of the toothed quadrant.
31Disconnect the clutch cable from the
clutch release arm, and pass the cable
through the bellhousing.
32Support the gearbox with a trolley jack,
using a block of wood between the jack and
the gearbox to spread the load.
33Unscrew and remove the remaining
engine-to-gearbox bolts, and remove the bolt
from the engine adapter plate (see
illustration). Recover any shims fitted
between the sump and the gearbox when
removing the lower engine-to-gearbox bolts.
5Engine - removal leaving
manual gearbox in vehicle
2B•4DOHC engine
5.5 Removing the hose support bracket
bolt from the cylinder head5.29 Removing the lower steering column
clamp bolt
5.33 Engine adapter plate bolt (arrowed)
5.22 Earth strap position on top engine-to-
gearbox (arrowed)
Warning: Vehicles equipped
with air conditioning:
Components of the air
conditioning system may
obstruct work being undertaken
on the engine and it is not always possible
to unbolt and move them aside
sufficiently, within the limits of their
flexible connecting pipes. In such a case,
the system should be discharged by a
Ford dealer or air conditioning specialist.
The refrigerant is harmless under normal
conditions but in the presence of a naked
flame (or a lighted cigarette) it forms a
highly toxic gas. Liquid refrigerant spilled
on the skin will cause frostbite. If
refrigerant enters the eyes, rinse them
with a diluted solution of boric acid and
seek medical advice immediately.

Dismantling
1Refer to Chapter 2, PartA, Section 18,
paragraphs 1 to 8 inclusive.
2A suitable selection of splined and Torx
sockets will be required to remove many of
the bolts when dismantling the engine.
3Before dismantling the main engine
components, the following externally-
mounted ancillary components can be
removed, with reference to the relevant
Chapters of this Manual and the relevant
Sections of this Chapter, where applicable.
Inlet manifold (and carburettor, if applicable)
Exhaust manifold
Alternator.
Coolant pump, and thermostat
Alternator/coolant pump drivebelt tensioner
Distributor cap, HT leads and spark plugs
Oil pressure warning lamp switch
Crankshaft speed/position sensor
Oil filter
Dipstick
Engine mounting brackets (if not already done)
Crankcase ventilation pipe and hoses
Clutch
Alternator mounting bracket.
Air conditioning compressor mounting
bracket (where applicable).
Engine lifting brackets.
Examination and renovation
4Refer to Chapter 2, PartA, Section 18, but
note that the connecting rod bolts should be
renewed on reassembly, and when renewing
the cylinder head bolts, the latest type bolts
with hexagonal heads should always be used.
Reassembly
5Proceed as described in Chapter 2, PartA,
Section 18, noting the following:
6If they have been removed, new cylinder
head bolts (both M11 and M8, of the latest
type with hexagonal heads), flywheel bolts,
and connecting rod bolts must be used.
Note: Refer to the warning at the beginning of
Section 5 before proceeding. A suitable puller
will be required to remove the crankshaft pulley.
A new crankshaft pulley bolt, a new timing chain
tensioner plunger assembly, new upper and
lower timing chain cover gaskets, and a new
camshaft cover gasket and reinforcing sleeve
sealing rings, must be used on refitting.
Removal
1If the engine is in the car, carry out the
following operations:
a)Disconnect the battery negative lead.
b)To improve access, remove the radiator. It
will be difficult to remove the crankshaft
pulley with the radiator in place.c)On carburettor models, remove the air
cleaner.
d)On fuel injection models, remove the air
inlet hose, plenum chamber, and air
cleaner lid as an assembly.
e)Disconnect the breather hose from the
camshaft cover.
f)Remove the distributor cap and HT leads,
and the rotor arm and housing.
2Proceed as described in paragraphs 2 to 11
inclusive of Section 18 (see illustration).
3Remove the alternator drivebelt.
4Slacken the crankshaft pulley bolt. Prevent
the crankshaft from turning by engaging top
gear (manual gearbox only) and having an
assistant press the brake pedal hard, or by
removing the starter motor and jamming the
ring gear teeth with a lever.
5Unscrew the bolt part-way, and use a puller
to remove the crankshaft pulley. The legs ofthe puller must be suitably shaped to enable
them to rest on the metal surfaces of the
pulley. Do not use a puller on the rubber
surface of the pulley (see illustrations).
15Timing chain and sprockets -
removal and refitting
14Engine dismantling,
examination, renovation and
reassembly - general information
2B•8DOHC engine
15.2 Timing chain, oil pump drive chain and associated components
1 Upper timing chain guide
2 Exhaust camshaft sprocket
3 Timing chain
4 Lower timing chain guide
5 Crankshaft sprocket (double)
6 Crankshaft
7 Oil pump chain tensioner
8 Oil pump drive chain
9 Oil pump10 Oil pressure relief valve
11 Oil passage to timing chain tensioner
plunger
12 Plug
13 Timing chain tensioner plunger
14 Timing chain tensioner sprocket
15 Timing chain tensioner arm
16 Inlet camshaft sprocket
17 Copper chain links
15.5a Remove the crankshaft pulley using
a puller (viewed from under vehicle)

42Fit a new upper timing chain guide to the
plate at the front of the cylinder head.
43Turn the crankshaft clockwise until the
inlet camshaft begins to turn.
44If the chain tensioner plunger piston
protrudes from the cylinder, unlatch the piston
by pressing the chain tensioner arm down by
hand.
45If the plunger piston is below the top
surface of the cylinder, a tool similar to that
shown(see illustration)must be fabricated to
unlatch the piston. It is suggested that a 2.5
mm diameter welding rod is used to
manufacture the tool. Use the tool to release
the piston as follows.
46Carefully lift the chain tensioner arm with
a screwdriver, and insert the tool between the
tensioner arm and the piston. Remove the
screwdriver, and release the piston by
pressing the tensioner arm down by hand.
Carefully withdraw the tool once the piston
has been released.
47Tighten the camshaft sprocket securing
bolts to the specified torque, holding the
sprockets stationary as during removal.
48Turn the crankshaft clockwise through
two complete revolutions, and check that the
timing marks on the camshaft sprockets are
still aligned with the top face of the cylinder
head as described in paragraph 4.
49Turn the crankshaft clockwise through
another complete revolution, and check that
the timing marks on the camshaft sprockets
are facing each other, directly in line with the
top face of the cylinder head. 50If the timing marks do not align as
described, the timing chain has been
incorrectly fitted (probably one chain link
away from the correct position on one of the
camshaft sprockets), and the chain should be
removed from the sprockets and refitted
again in the correct position as described
previously.
51Inspect the oil seal in the upper timing
chain cover. If the oil seal is in good condition,
the cover can be refitted as follows, but if the
seal is damaged, or has been leaking, a new
seal should be fitted to the cover. If
necessary, carefully prise the old oil seal from
the cover using a screwdriver, and drive in the
new seal using a suitable metal tube. Make
sure that the seal lip faces into the engine.
Take care not to damage the timing chain
cover.
52Fit the upper timing chain cover using a
new rubber gasket. Great care must be taken
to avoid damage to the oil seal when passing
the seal over the end of the inlet camshaft.
Careful manipulation will be required (possibly
using a thin feeler blade) to avoid damage to
the oil seal sealing lip. Note that the oil seal
should be fitted dry.
53Refit the timing chain cover securing bolts
and studs in their original locations, and
tighten them to the specified torque (see
illustration).
54Remove the reinforcing sleeves from the
camshaft cover, and renew the rubber sealing
rings. Note that the four short reinforcing
sleeves fit at the front of the cover (see
illustration).
55Refit the camshaft cover using a new
gasket, and tighten the securing bolts and
studs to the specified torque.
Note: A valve spring compressor will be
required during this procedure. New valve
stem oil seals should be used on reassembly.
1Proceed as described in Chapter 2, PartC,
noting the following points:
a)Ignore the references to removing and
refitting the camshaft.
b)Double valve springs are used on all the
valves (see illustration).c)Ignore the reference to inlet valve
dampers.
d)Refer to the following Section if the
cylinder head is to be inspected and
renovated.
1Refer to Chapter 2, PartA, noting the
following points:
a)Valve and valve seat cutting and
regrinding can be carried out using
conventional tools.
b)The cylinder head cannot be resurfaced,
and if the surface distortion exceeds the
specified limits, the cylinder head must be
renewed.
Note: Once the timing chain has been
removed from the camshaft sprockets, do not
turn the crankshaft until the timing chain has
been correctly refitted - this is to prevent
contact between the valves and pistons. A
new timing chain tensioner plunger assembly,
a new upper timing chain cover gasket, and a
new camshaft cover gasket and reinforcing
sleeve sealing rings, must be used on refitting.
Removal
1If the engine is in the vehicle, carry out the
following operations:
a)Disconnect the battery negative lead.
b)On carburettor models, remove the air
cleaner.
c)On fuel injection models, remove the air
inlet hose, plenum chamber, and air
cleaner lid as an assembly.
d)Disconnect the breather hose from the
camshaft cover.
e)Remove the distributor cap and HT leads,
and the rotor arm and housing. If
necessary, mark the HT leads to aid
refitting.
2Proceed as described in paragraphs 2 to 15
inclusive of Section 18.
21Camshafts and cam
followers - removal, inspection
and refitting
20Cylinder head - inspection
and renovation
19Cylinder head - dismantling
and reassembly
2B•14DOHC engine
18.45 Fabricated tool used to unlatch
tensioner plunger piston
18.54 Fitting a camshaft cover reinforcing
sleeve and sealing ring
19.1 Withdrawing the double valve springs
from the cylinder head
18.53 Upper timing chain cover securing
stud locations (arrowed)