1992 FORD SIERRA fuel filter

1.8 litre (R6A type) engine
Note: Unless otherwise stated, the Specifications for this later version of the 1.8 litre CVH engine are as given for the earlier R2A type above.
General
Engine code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .R6A
Maximum continuous engine speed . . . . . . . . . . . . . . . . . . . . . . . . . . . .5700 rpm
Maximum engine power (DIN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64 kW at 5200 rpm
Maximum engine torque (DIN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145 Nm at 3000 rpm
Valve timing
Inlet opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24º BTDC
Inlet closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116º BTDC
Exhaust opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110º ATDC
Exhaust closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18º ATDC
1.6 litre engine
The 1.6 litre CVH engine was introduced in
September 1991, to replace the 1.6 litre
SOHC engine used previously in the Sierra
range. The engine is broadly similar to the 1.8
litre (R2A type) CVH engine described below.
The main differences are outlined in the
following paragraphs.
The centre main bearing is fitted with
thrustwashers to control crankshaft endfloat,
instead of a flanged bearing shell.
The hydraulic cam followers operate in a
similar manner to those described for the 1.8
litre (R2A) engine but no rollers are fitted, and
the base of each cam follower is in direct
contact with the cam profile.
A distributorless ignition system is used and
a blanking plate is therefore fitted to the cylinder
head in place of the distributor drive. The
electric fuel pump is mounted in the fuel tank.
A comprehensive emissions control system
is fitted, comprising Central Fuel Injection
(CFI), a sophisticated engine management
system, a crankcase ventilation system, a
catalytic converter, and a pulseair system (to
reduce exhaust gas emissions).
Unless otherwise stated, all procedures are
as described for the 1.8 litre (R2A) engine.
1.8 litre (R2A type) engine
The CVH (Compound Valve angle,
Hemispherical combustion chambers) engine
is of four-cylinder, in-line, single overhead
camshaft type. The engine was introduced to
replace the 1.8 SOHC engine previously used
in the range.
The crankshaft incorporates five main
bearings. The centre main bearing has a
flanged bearing shell (thrust bearing) fitted to
the cylinder block to control crankshaft endfloat
The camshaft is driven by a toothed belt and
operates the compound angled valves via roller
type hydraulic cam followers, which eliminates
the need for valve clearance adjustment. The
cam followers operate in the following way.
When the valve is closed, pressurised engine
oil passes through ports in the body of the cam
follower and the plunger into the cylinder feed
chamber. From this chamber, oil flows through
a ball type non-return valve into the pressurechamber. The tension of the coil spring causes
the plunger to press the rocker arm against the
valve and to eliminate any free play.
As the cam lifts the cam follower, the oil
pressure in the pressure chamber increases
and causes the non-return valve to close the
port to the feed chamber. As oil cannot be
compressed, it forms a rigid link between the
body of the cam follower, the cylinder and the
plunger which then rise as one component to
open the valve.
The clearance between the body of the cam
follower and the cylinder is accurately designed
to meter a specific quantity of oil as it escapes
from the pressure chamber. Oil will only pass
along the cylinder bore when pressure is high
during the moment of valve opening. Once the
valve has closed, the escape of oil will produce
a small amount of free play and no pressure will
exist in the pressure chamber. Oil from the feed
chamber can then flow through the non-return
valve into the pressure chamber so that the
cam follower cylinder can be raised by the
pressure of the coil spring, thus eliminating any
play in the arrangement until the valve is
operated again.
As wear occurs between rocker arm and
valve stem, the quantity of oil which flows into
the pressure chamber will be slightly more
than the quantity lost during the expansion
cycle of the cam follower. Conversely, when
the cam follower is compressed by the
expansion of the valve, a slightly smaller
quantity of oil will flow into the pressure
chamber than was lost.
To reduce valve clatter when the engine is
started, a small plastic stand pipe retains oil
inside the plunger. When the engine is started,
the reservoir in the plunger (and via the non-
return valve, the pressure chamber) are
immediately filled with oil. This reduces the
noise often associated with hydraulic cam
followers as they pressurise with oil after
engine start-up.
The cam follower rollers run in needle
bearings, which greatly reduces friction as the
rollers follow the cam profile.
The distributor and fuel pump are driven
directly from the camshaft and the oil pump is
driven directly from the front of the crankshaft.
The cylinder head is of crossflow design,
with the inlet manifold mounted on the right-
hand side and the exhaust manifold mounted
on the left-hand side.
Lubrication is by means of a bi-rotor pumpwhich draws oil through a strainer located
inside the sump and forces it through a full-
flow filter into the oil galleries where it is
distributed to the crankshaft and camshaft.
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 big-ends. The hydraulic
cam followers are supplied with oil from the
camshaft bearings via short passages in the
cylinder head.
A semi-closed crankcase ventilation system
is employed whereby piston blow-by gases
are drawn from the crankcase, through the
camshaft cover via an external vent hose, out
to an oil separator built into the base of the air
cleaner.
1.8 litre (R6A type) engine
The 1.8 litre (R6A type) CVH engine,
introduced in March 1992, is a further
development of the earlier 1.8 litre (R2A type)
unit described above. Apart from minor
engineering modifications to provide
increased fuel economy, reliability and power
output, the engine is mechanically identical to
the earlier version.
In common with the 1.6 litre unit, a
distributorless ignition system is used,
together with a comprehensive emissions
control system comprising Central Fuel
Injection (CFI), a sophisticated engine
management system, a crankcase ventilation
system, a catalytic converter, and additionally,
an exhaust gas recirculation (EGR) system.
Unless otherwise stated, all procedures are
as described for the 1.8 litre (R2A type)
engine.
Refer to Section 2, Chapter 2, Part A.
Refer to Chapter 1, Section 35.
Refer to Section 5, Chapter 2, Part A.
4Compression test
3Crankcase ventilation system -
inspection and maintenance
2Engine oil and filter - renewal
1General information
CVH engines 2C•5
2C

1.8 litre (R2A type)
Dismantling
1It is best to mount the engine on a
dismantling stand, but if this is not available,
stand the engine on a strong bench at a
comfortable working height. Failing this, it will
have to stripped down on the floor.
2Cleanliness is most important, and if the
engine is dirty, it should be cleaned with
paraffin while keeping it in an upright position.
3Avoid working with the engine directly on a
concrete floor, as grit presents a real source
of trouble.
4As parts are removed, clean them in a
paraffin bath. However, do not immerse parts
with internal oilways in paraffin as it is difficult
to remove, usually requiring a high pressure
hose. Clean oilways with nylon pipe cleaners.
5It is advisable to have suitable containers
available to hold small items according to
their use, as this will help when reassembling
the engine and also prevent possible losses.
6Always obtain a complete set of new
gaskets for use during engine reassembly, but
retain the old gaskets with a view to using
them as a pattern to make a replacement if a
new one is not available.
7Where possible, refit securing nuts, bolts
and washers to their locations after removing
the relevant components. This will help to
protect the threads and will also prevent
possible losses.
8Retain unserviceable components in order
to compare them with the new components
supplied.
9A suitable Torx socket will be required to
remove the oil pump cover securing screws.
10Before dismantling the main engine
components, the following externally mounted
ancillary components can be removed:
Inlet manifold and carburettor
Exhaust manifold
Fuel pump and operating pushrod
Alternator
Spark plugs
Oil pressure warning lamp switch (see
illustration)
Oil filter
Dipstick
Engine mounting brackets
Clutch
Alternator mounting bracket
Crankshaft speed/position sensor
Engine lifting brackets
Examination and renovation
11Refer to Section 18 in Chapter 2, PartA.
Reassembly
12To ensure maximum life with minimum
trouble from a rebuilt engine, not only must
everything be correctly assembled, but it mustalso be spotlessly clean. All oilways must be
clear, and locking washers and spring
washers must be fitted where indicated. Oil all
bearings and other working surfaces
thoroughly with engine oil during assembly.
13Before assembly begins, renew any bolts
or studs with damaged threads.
14Gather together a torque wrench, oil can,
clean rag, and a set of engine gaskets and oil
seals, together with a new oil filter.
15If they have been removed, new cylinder
head bolts, big-end bolts/nuts and new
flywheel bolts will be required.
16After reassembling the main engine
components, refer to paragraph 10 and refit
the ancillary components listed. Delicate
items such as the alternator may be left until
after the engine has been refitted.
1.6 and 1.8 litre (R6A type)
Dismantling
17Refer to paragraphs 1 to 9 inclusive.
18Before dismantling the main engine
components, the following ancillary
components can be removed:
Inlet manifold and CFI unit.
Exhaust manifold .
Alternator.
Spark plugs and HT leads.
Ignition coil and mounting bracket.
Oil pressure warning lamp switch.
Oil filter.
Dipstick and tube.
Engine mounting brackets.
Clutch.
Alternator mounting bracket.Crankshaft speed/position sensor.
Engine lifting brackets.
Crankcase ventilation hose.
Examination and renovation
19Refer to Section 18 in Chapter 2, PartA.
Reassembly
20Refer to paragraphs 12 to 16 but note that
new rocker arm nuts will be required, if they
have been removed.
Note: The belt tension should be checked
using Ford special tool No 21-113 after
refitting. A suitable puller may be required to
remove the sprockets. If the camshaft
sprocket is removed, a new retaining bolt
must be used on refitting, and suitable sealant
(Loctite 74 or 274, or Omnifit 30M blue) will be
required to coat the bolt threads.
1.8 litre (R2A type)
Removal
1If the engine is in the vehicle, carry out the
following operations:
a)Disconnect the battery negative lead
b)Remove the alternator drivebelt
c)Remove the distributor cap, rotor arm and
housing
d)Disconnect the wiring plug from the
crankshaft speed/position sensor
e)Unclip the coolant hoses from the timing
cover, and position them across the top
of the camshaft cover out of the way
f)If desired for improved access, remove
the fan shroud and cooling fan assembly,
although this is not essential
2Slacken the crankshaft pulley bolt. Prevent
the crankshaft from turning by engaging top
gear (manual gearbox only) and having an
assistant apply the brake pedal hard, or by
removing the starter motor and jamming the
ring gear teeth with a lever.
3Remove the bolt and washer and withdraw
the pulley (see illustration). If the pulley will
not come off easily, refit the bolt part way and
use a puller, but take care not to damage the
sensor toothed disc.
18Timing belt and sprockets -
removal and refitting
17Engine dismantling,
examination, renovation and
reassembly - general information
2C•10CVH engines
17.10 Removing the oil pressure warning
lamp switch - 1.8 litre (R2A)
18.5 Withdrawing the timing cover -
1.8 litre (R2A)18.3 Withdrawing the crankshaft pulley -
1.8 litre (R2A)