1991 FORD SIERRA inlet manifold

Torque wrench settingsNmlbf ft
Main bearing cap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90 to 10466 to 77
Connecting rod (big-end bearing cap) bolts:
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 to 84 to 6
Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 to 1711 to 13
Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Angle-tighten a further 85º
Crankshaft pulley bolt:
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45 to 5833 to 43
Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Angle-tighten a further 80º
Camshaft sprocket bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55 to 6341 to 46
Flywheel bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82 to 9261 to 68
Oil pump bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 to 127 to 9
Oil pump sprocket bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16 to 1912 to 14
Oil pump chain tensioner bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 to 137 to 10
Sump bolts and nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 to 106 to 7
Sump studs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 to 84 to 6
Sump drain plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 to 2815 to 21
Sump front mounting plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23 to 2817 to 21
Oil baffle nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17 to 2113 to 15
Oil pick-up pipe-to-cylinder block bolts . . . . . . . . . . . . . . . . . . . . . . . . .9 to 137 to 10
Oil pressure warning lamp switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 to 2213 to 16
Cylinder head bolts:
M11 bolts:
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4030
Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5541
Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Angle-tighten a further 90º
Stage 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Angle-tighten a further 90º
M8 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36 to 3927 to 29
Camshaft cover bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 to 84 to 6
Camshaft bearing cap nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 to 2616 to 19
Lower timing chain guide upper bolt . . . . . . . . . . . . . . . . . . . . . . . . . . .10 to 137 to 10
Lower timing chain guide lower bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . .24 to 2818 to 21
Upper and lower timing chain cover bolts . . . . . . . . . . . . . . . . . . . . . . .7 to 105 to 7
Crankshaft rear oil seal housing bolts . . . . . . . . . . . . . . . . . . . . . . . . . .8 to 116 to 8
Engine-to-gearbox/transmission bolts . . . . . . . . . . . . . . . . . . . . . . . . . .29 to 4121 to 30
The 2.0 litre DOHC (Double OverHead
Camshaft) engine was introduced in August
1989 to replace the 2.0 litre SOHC engine
used previously in the Sierra range. The
engine is of four-cylinder, in-line type.
The crankshaft incorporates five main
bearings. Thrustwashers are fitted to the
centre main bearing in order to control
crankshaft endfloat.
The camshafts are driven by a chain from
the crankshaft, and operate the angled valves
via hydraulic cam followers. One camshaft
operates the inlet valves, and the other
operates the exhaust valves. The operation of
the cam followers is explained in Chapter 2,
Part C, but note that no rollers are fitted and
the base of each cam follower is in direct
contact with the cam profile.
The distributor is driven directly from the
front of the inlet camshaft, and the oil pump is
driven by a chain from the crankshaft. An
electric fuel pump is mounted in the fuel tank.Lubrication is by means of a bi-rotor pump
which draws oil through a strainer located
inside the sump, and forces it through a full-
flow filter into the engine oil galleries, from
where it is distributed to the crankshaft and
camshafts. The big-end bearings are supplied
with oil via internal drillings in the crankshaft.
The undersides of the pistons are supplied
with oil from drillings in the connecting rods.
The hydraulic cam followers are supplied with
oil from passages in the cylinder head. The
camshafts are lubricated by oil from spray
tubes mounted above the camshaft bearing
caps.
A closed crankcase ventilation system is
employed, whereby piston blow-by gases are
drawn from the crankcase, through a breather
pipe into the inlet manifold, where they are
burnt with fresh air/fuel mixture.
Refer to Chapter 1, Section 35.The following operations can be carried out
without removing the engine from the vehicle:
a)Removal of the camshafts.
b)Removal and servicing of the cylinder head
c)Removal of the timing chain and
sprockets.
d)Removal of the oil pump.
e)Removal of the sump.
f)Removal of the pistons and connecting
rods.
g)Removal of the big-end bearings.
h)Removal of the engine mountings
i)Removal of the clutch and flywheel.
j)Removal of the crankshaft front and rear
oil seals.
The following operation can only be carried out
after removing the engine from the vehicle:
a)Removal of the crankshaft and main
bearings.
4Major operations requiring
engine removal
3Major operations possible with
the engine in the vehicle
2Crankcase ventilation system -
inspection and maintenance
1General information
DOHC engine 2B•3
2B

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)

should be fitted dry. Drive in the new seal
using a suitable metal tube, making sure that
the seal lip faces into the engine, and taking
care not to damage the timing chain cover
(see illustration).
31Fit the lower timing chain cover using a
new rubber gasket (see illustration).
32Loosely refit the timing chain cover
securing bolts.
33Refit the crankshaft pulley to the end of the
crankshaft, and draw the pulley onto the
crankshaft using the original securing bolt, at the
same time centring the lower timing chain cover.
34With the lower timing chain cover
centralised, and the pulley fully home on the
crankshaft, remove the old securing bolt, then
fit a new bolt.
35Tighten the new crankshaft pulley bolt to
the specified torque, in the two stages given
in the Specifications at the beginning of this
Chapter. Prevent the crankshaft from turning
as during removal.
36Tighten the lower timing chain cover
securing bolts.
37Refit the drivebelt tensioner assembly,
ensuring that the lug on the rear of the
tensioner bracket engages with the
corresponding hole in the cylinder block, and
tighten the securing bolt.
38Swing the alternator into position to align
the upper mounting bolt hole with the
corresponding hole in the drivebelt tensioner
assembly, then refit the upper mounting bolt,
and tighten the upper bolt and the lower
through-bolt.
39Refit the alternator drivebelt.
40If the engine is in the vehicle, reverse the
operations described in paragraph 1.
41If applicable, refill the cooling system.
1Examine alI the teeth on the camshaft and
crankshaft sprockets. If the teeth are “hooked”
in appearance, renew the sprockets.
2Examine the chain tensioner plastic
sprocket for wear. If excessive wear is
evident, the complete tensioner assembly
must be renewed, as the sprocket cannot be
renewed independently. Note that the
tensioner plunger assembly must be renewed
whenever the timing chain is removed.3Examine the timing chain for wear. If the
chain has been in operation for a considerable
time, or if when held horizontally (rollers
vertical) it takes on a deeply-bowed
appearance, renew it.
Note: Refer to the warning at the beginning of
Section 5 and the note at the beginning of the
following Section before proceeding. The
cylinder head must not be removed when the
engine is warm.
Removal
1Disconnect the battery negative lead.
2On carburettor models, remove the air
cleaner.
3On fuel injection models, remove the air
inlet hose, plenum chamber, and air cleaner
lid as an assembly.
4Drain the cooling system.
5Disconnect the heater coolant hose from
the inlet manifold (see illustration).
6Disconnect the breather hose from the
camshaft cover, and unbolt the hose bracket
from the left-hand side of the cylinder head
(see illustration).
7Unscrew the securing bolt and disconnect
the earth lead from the left-hand rear of the
cylinder head (see illustration).
8Remove the distributor cap and HT leads,
and the rotor arm and housing. If necessary,
mark the HT leads to aid refitting.
9The cylinder head can be removed either
with or without the manifolds and fuel rail,
where applicable (it is easiest to remove thehead complete with the manifolds and fuel
rail). If desired, the inlet manifold and the fuel
rail can be unbolted and moved to one side,
leaving the wires, hoses, pipes and cables
connected, but care must be taken not to
place any strain on them.
10Unscrew the three securing nuts and
disconnect the exhaust downpipe from the
manifold. It may be necessary to jack up the
front of the vehicle to gain access to the nuts
(in which case, apply the handbrake and
support the front of the vehicle securely on
axle stands). Recover the gasket.
11If the inlet manifold and the fuel rail (where
applicable) are to be removed with the
cylinder head, disconnect all relevant wires,
hoses, pipes and cables. Otherwise, unbolt
the manifold and the fuel rail, and move them
to one side, ensuring that they are adequately
supported. If the fuel rail is unbolted, be
prepared for fuel spillage, and take adequate
fire precautions.
12Proceed as shown in paragraphs 2 to 19
of Section 18.
Refitting
13Proceed as shown in paragraphs 20 to 55
of Section 18.
14With the cylinder head refitted, reverse the
procedure described in paragraphs 1 to 11,
noting the following points.
15Use a new gasket when reconnecting the
exhaust downpipe to the manifold.
16Ensure that the HT leads are reconnected
correctly.
17Fill the cooling system.
17Cylinder head - removal and
refitting (engine in vehicle)
16Timing chain, sprockets and
tensioner - examination and
renovation
2B•10DOHC engine
15.30 Fitting a new lower timing chain
cover oil seal
17.5 Disconnecting the heater coolant
hose from the inlet manifold17.7 Disconnect the earth lead (arrowed)
from the cylinder head17.6 Hose bracket bolted to cylinder head
(arrowed)
15.31 Lower timing chain cover rubber
gasket in position. Ensure that lug on
gasket engages with notch in cover
(arrowed)

Note: New cylinder head bolts, a new cylinder
head gasket, 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
1With the manifolds removed, proceed as
follows.
2Unscrew the eleven bolts and four nuts,
and remove the camshaft cover. Recover the
gasket.
3Unscrew the four securing bolts and three
studs, and remove the upper timing chain
cover. Note the locations of the studs to aid
refitting.
4Using a spanner on the crankshaft pulley,
turn the crankshaft to bring No 1 piston to the
firing point. With No 1 piston at the firing
point, the timing marks on the camshaft
sprockets should be pointing away from each
other, and should be approximately level withthe top edge of the cylinder head. Timing
notches are provided in the camshaft
sprockets, and corresponding paint marks are
provided on the outside edges of the
sprockets (see illustration).
5Hold the inlet camshaft sprocket stationary
using an improvised tool similar to that
shownthen unscrew the camshaft sprocket
bolt and remove the distributor rotor shaft
(see illustration).
6Repeat the procedure given in the previous
paragraph for the exhaust camshaft, but note
that a spacer is fitted in place of the
distributor rotor shaft.
7Squeeze the upper timing chain guide
securing lugs together, using pliers if
necessary, and withdraw the guide from the
plate at the front of the cylinder head (see
illustrations).
8Mark the position of the timing chain in
relation to the camshaft sprockets, so that the
chain can be refitted in precisely its original
position (ie, make alignment marks between
each sprocket and a corresponding link in the
chain), then slide the camshaft sprockets from
the camshafts. Withdraw the sprockets and
lay the timing chain over the exhaust side of
the timing case, having eliminated the slack inthe chain. Secure the chain using a cable-tie
through two of the chain links, to prevent it
from dropping off the crankshaft sprocket.
9Using a suitable pair of pliers, extract the
circlip from the chain tensioner arm pivot pin,
taking care not to drop it into the timing case,
then withdraw the pivot pin from the tensioner
arm (see illustrations). If the pivot pin proves
difficult to withdraw, an M6 bolt can be
screwed into its end to facilitate removal.
10Lift the chain tensioner arm from the
timing case.
18Cylinder head - removal and
refitting (engine removed)
DOHC engine 2B•11
2B
18.7a Upper timing chain guide securing
lugs (arrowed)
18.9b Withdrawing the pivot pin from the
chain tensioner arm18.9a Removing the chain tensioner arm
pivot pin circlip18.7b Removing the upper timing chain
guide
18.5 Removing the inlet camshaft sprocket bolt and the distributor
rotor shaft
18.4 Timing mark positions with No 1
cylinder at TDC