oil type FORD SIERRA 1991 2.G DOHC Engine Workshop Manual

General
Engine type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Four-cylinder, in-line, double overhead camshaft
Engine code:
Carburettor engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N8A
Fuel injection engine without catalyst . . . . . . . . . . . . . . . . . . . . . . . . . N9A
Fuel injection engine with catalyst . . . . . . . . . . . . . . . . . . . . . . . . . . . N9C
Bore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.00 mm
Stroke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.00 mm
Cubic capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1998 cc
Compression ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.3 : 1
Compression pressure at starter motor speed . . . . . . . . . . . . . . . . . . . . 11 to 13 bars
Maximum continuous engine speed:
N8A engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6050 rpm
All engines except N8A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5950 rpm
Maximum engine power (DIN):
N8A engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 kW at 5600 rpm
N9A engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 kW at 5500 rpm
N9C engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 kW at 5500 rpm
Maximum engine torque:
N8A engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174 Nm at 3000 rpm
N9A engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174 Nm at 2500 rpm
N9C engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171 Nm at 2500 rpm
Cylinder bore diameter
Standard class 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.000 to 86.010 mm
Standard class 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.010 to 86.020 mm
Oversize 0.15 class A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.150 to 86.160 mm
Oversize 0.15 class B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.160 to 86.170 mm
Oversize 0.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.500 to 86.510 mm
Chapter 2 Part B:
DOHC engine
Camshafts and cam followers - removal, inspection and refitting . . .21
Crankcase ventilation system - inspection and maintenance . . . . . . .2
Crankshaft and bearings - examination and renovation . . . . . . . . . .31
Crankshaft and main bearings - removal and refitting . . . . . . . . . . . .30
Crankshaft front oil seal - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Crankshaft rear oil seal - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Cylinder head - dismantling and reassembly . . . . . . . . . . . . . . . . . . .19
Cylinder head - inspection and renovation . . . . . . . . . . . . . . . . . . . . .20
Cylinder head - removal and refitting (engine in vehicle) . . . . . . . . . .17
Cylinder head - removal and refitting (engine removed) . . . . . . . . . . .18
Engine/automatic transmission assembly - removal and separation . .8
Engine/automatic transmission assembly - reconnection and
refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Engine dismantling, examination, renovation and reassembly - general
information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Engine/manual gearbox assembly - removal and separation . . . . . . .7
Engine/manual gearbox assembly - reconnection and refitting . . . . .11Engine - refitting (manual gearbox in vehicle) . . . . . . . . . . . . . . . . . . . .9
Engine - refitting (automatic transmission in vehicle) . . . . . . . . . . . . .10
Engine - removal leaving manual gearbox in vehicle . . . . . . . . . . . . . .5
Engine - removal leaving automatic transmission in vehicle . . . . . . . .6
Engine mountings - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Flywheel/driveplate - removal, inspection and refitting . . . . . . . . . . .22
General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Initial start-up after overhaul or major repair . . . . . . . . . . . . . . . . . . .32
Major operations possible with the engine in the vehicle . . . . . . . . . . .3
Major operations requiring engine removal . . . . . . . . . . . . . . . . . . . . .4
Oil pump drive chain and sprockets - examination and renovation . .28
Oil pump - dismantling, inspection and reassembly . . . . . . . . . . . . .27
Oil pump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Pistons and connecting rods - removal and refitting . . . . . . . . . . . . .29
Sump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Timing chain and sprockets - removal and refitting . . . . . . . . . . . . . .15
Timing chain, sprockets and tensioner - examination and renovation .16
2B•1
Specifications Contents
2B
Unless otherwise stated, procedures are as described for the SOHC engines in Part A of this Chapter.
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert
DIY or professional
Degrees of difficulty

Crankshaft
Endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.090 to 0.300 mm (0.004 to 0.012 in)
Main bearing running clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.011 to 0.048 mm
Main bearing journal diameter:
Standard (yellow) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54.980 to 54.990 mm
Standard (red) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54.990 to 55.000 mm
Undersize 0.25 (green) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54.730 to 54.750 mm
Main bearing thrustwasher thickness:
Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.301 to 2.351 mm (0.090 to 0.093 in)
Oversize 0.38 (yellow) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.491 to 2.541 mm (0.098 to 0.100 in)
Big-end bearing running clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.006 to 0.060 mm
Big-end bearing journal diameter:
Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50.890 to 50.910 mm
Undersize 0.25 (green) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50.640 to 50.660 mm
Pistons and piston rings
Piston diameter:
Standard 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85.970 to 85.980 mm
Standard 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85.980 to 85.990 mm
Standard service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85.980 to 85.990 mm
Oversize 0.15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86.130 to 86.150 mm
Oversize 0.50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86.470 to 86.490 mm
Piston ring end gap:
Top . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.300 to 0.600 mm (0.012 to 0.024 in)
Centre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.500 to 0.800 mm (0.020 to 0.032 in)
Bottom (oil control) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.400 to 1.500 mm (0.016 to 0.059 in)
Cylinder head
Valve guide bore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.063 to 7.094 mm
Camshaft bearing parent bore diameter . . . . . . . . . . . . . . . . . . . . . . . .26.000 to 26.030 mm
Camshafts
Endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.020 to 0.260 mm (0.001 to 0.010 in)
Valves
Valve timing:
Carburettor engines:
Inlet opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13º BTDC
Inlet closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39º ABDC
Exhaust opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43º BBDC
Exhaust closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13º ATDC
Fuel injection engines:
Inlet opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13º BTDC
Inlet closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51º ABDC
Exhaust opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43º BBDC
Exhaust closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13º ATDC
Valve spring free length:
Inner spring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48.200 mm (1.899 in)
Outer spring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46.800 mm (1.844 in)
Inlet valve stem diameter:
Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.025 to 7.043 mm
Oversize 0.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.225 to 7.243 mm
Oversize 0.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.425 to 7.443 mm
Oversize 0.6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.625 to 7.643 mm
Oversize 0.8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.825 to 7.843 mm
Exhaust valve stem diameter:
Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6.999 to 7.017 mm
Oversize 0.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.199 to 7.217 mm
Oversize 0.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.399 to 7.417 mm
Oversize 0.6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.599 to 7.617 mm
Oversize 0.8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.799 to 7.817 mm
Lubrication system
Oil type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Multigrade engine oil, viscosity range SAE 10W/30 to 20W/50, to API
SG/CD or better
Oil capacity:
With filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.5 litres (7.9 pints)
Without filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.0 litres (7.0 pints)
Oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion C102
2B•2DOHC engine

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

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)

6Loosen the alternator lower mounting
through-bolt, then remove the alternator
upper mounting bolt, and swing the alternator
away from the engine.
7Unscrew the central securing bolt, and
withdraw the drivebelt tensioner assembly.
8Unscrew the eleven securing bolts, and
remove the lower timing chain cover. Recover
the rubber gasket.
9Using a suitable Torx socket, unscrew the
securing screw, and carefully withdraw the oil
pump chain tensioner (see illustration).
10Unscrew the Torx type securing bolt, and
withdraw the oil pump sprocket, complete
with the oil pump drive chain.
11Unscrew the two lower timing chain guide
securing bolts, noting their locations, and
withdraw the timing chain guide through the
top of the timing case (see illustration).
12Remove the Woodruff key from the end of
the crankshaft, prising it free with a
screwdriver if necessary, then slide the double
chain sprocket from the end of the crankshaft,
and lift the chain from the sprocket (see
illustration).
13Withdraw the timing chain through the top
of the timing case and, where applicable,
remove the cable-tie from the chain (see
illustration).
Refitting
14Commence refitting as follows. Note that
coppered links are provided in the timing
chain to assist with refitting, but these can be
difficult to see on a chain which has already
been in service. If possible, position thecoppered links as described during the
following procedure. If the coppered links are
not visible, the chain should still be refitted as
described, but ignore the references to the
coppered links.
15Make sure that the slot for the Woodruff
key in the end of the crankshaft is pointing
vertically downwards. If necessary,
temporarily refit the crankshaft pulley bolt in
order to turn the crankshaft to the required
position.
16Lower the timing chain into the timing
case from above, with the single coppered
link at the bottom. If desired, use a cable-tie
to prevent the chain from dropping into the
timing case, as during removal.
17Locate the double chain sprocket loosely
over the end of the crankshaft (larger sprocket
nearest the crankcase), with the timing mark
pointing vertically down.
18Fit the chain over the inner, larger
sprocket, aligning the coppered link in the
chain with the timing mark on the sprocket
(see illustration).
19Coat the threads of the lower timing chain
guide lower securing bolt with a suitable
thread-locking compound.
20Introduce the lower timing chain guide
through the top of the timing case,
manipulating the chain around the guide as
necessary, then fit the chain guide lower
securing bolt and tighten it finger-tight.
21Push the double chain sprocket onto the
crankshaft, engaging the notch in the
sprocket with the groove in the end of the
crankshaft.22Proceed as shown in paragraphs 34 to 42
of Section 18 but when fitting the chain over
the camshaft sprockets, align the timing mark
on each sprocket between the two
corresponding coppered links in the chain.
23Coat the threads of the lower timing chain
guide upper securing bolt with a suitable
thread-locking compound, then fit the bolt
and tighten it finger-tight.
24Proceed as shown in paragraphs 43 to 46
of Section 18.
25Tighten the two chain guide securing
bolts to the specified torque.
26Proceed as shown in paragraphs 47 to 55
of Section 18.
27Fit the oil pump drive chain around the
outer crankshaft sprocket and the oil pump
sprocket, then refit the oil pump sprocket, and
tighten the securing bolt to the specified
torque. If necessary, a screwdriver can be
inserted through one of the holes in the
sprocket to prevent it from turning as the
securing bolt is tightened.
28Refit the oil pump drive chain tensioner,
and tighten the securing bolt to the specified
torque.
29Refit the Woodruff key to the end of the
crankshaft.
30Inspect the oil seal in the lower 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. The new seal
DOHC engine 2B•9
2B
15.11 Withdrawing the lower timing chain
guide
15.18 Coppered link in timing chain aligned
with crankshaft sprocket timing mark
(arrowed)15.13 Withdrawing the timing chain
through the top of the timing case
15.9 Oil pump chain tensioner securing
screw (arrowed)15.5b Position the legs of the puller on the
metal surfaces of the pulley (A), not the
rubber surface (B)
15.12 Sliding the double chain sprocket
from the end of the crankshaft

26Insert the three smaller M8 cylinder head
bolts through the top of the timing case and
tighten them to the specified torque. Note that
new bolts must be used, and that they should
be of the latest type, with hexagonal heads
(see illustration).
27Lubricate the cam follower bores in the
cylinder head, and the cam followers
themselves, then insert the cam followers into
their original locations in the cylinder head.
28Lubricate the camshaft bearing surfaces
in the cylinder head, and the bearing caps.
29Lubricate the surfaces of the camshafts,
then carefully lay the camshafts in their
original positions in the cylinder head.
Position the camshafts with the slots in their
front ends pointing away from each other.
30Fit and tighten the bearing caps L1, L3,
L5, R1, R3, and R5 in the sequence shown
(see illustration)then lay the camshaft oil
spray bars and the timing chain guide plate in
position over the studs (see illustrations).
31Carefully tighten the bearing cap securing
nuts by hand in the following sequence to
lower the camshafts into position. Continue to
tighten the nuts in the sequence given, in
small amounts, until the bearing caps contact
the cylinder head.1Tighten the nuts for bearing caps L1 and
R1 by half-a-turn (180º)
2Tighten the nuts for bearing caps L5 and
R5 by half-a-turn (180º)
3Tighten the nuts for bearing caps L3 and
R3 by half-a-turn (180º)
32Fit bearing caps L2, L4, R2 and R4, and
tap them into position on the cylinder head
using light taps from a soft-faced mallet.
Tighten the securing nuts evenly by hand.
33Tighten all the bearing cap nuts to the
specified torque in half-turn stages, using the
following sequence:
1L1 and R1
2L5 and R5
3L3 and R3
4L2 and L4
5R2 and R4
34Fit a newchain tensioner plunger
assembly to the housing in the cylinder head
with the piston uppermost. Before fitting the
new plunger assembly, take note of the
position of the piston(see illustration). The
assembly is normally supplied with the piston
protruding slightly from the cylinder, or slightly
below the top surface of the cylinder (“A”). If
the new assembly is supplied with the piston
partially unlatched (“B”), or fully unlatched
with the latching ring visible (“C”), it must not
be used (see illustration).
35Locate the chain tensioner arm in
position, then insert the pivot pin, and secure
it with the circlip. Take care not to drop the
circlip into the timing-case.
36Release the cable-tie securing the timing
chain (if used), and lay the chain over the
exhaust camshaft sprocket, aligning the
marks made previously on the chain and
sprocket, so that the timing chain is taut on
the exhaust side of the engine.
37Fit the sprocket to the exhaust camshaft,
with the camshaft in the TDC position (ie with
the exhaust camshaft sprocket timing mark in
line with the top edge of the cylinder head,
pointing to the exhaust side of the engine -
see paragraph 4. If necessary, use a pair of
pliers on one of the unmachined sections of
the camshaft to turn the camshaft to the TDCposition. Take care not to damage the
machined surfaces of the camshaft.
38With the sprocket fitted, fit the spacer to
the end of the camshaft, and tighten the
securing bolt finger-tight (see illustration).
39Lay the timing chain over the inlet
camshaft sprocket, aligning the marks made
previously on the chain and the sprocket.
40Fit the sprocket to the inlet camshaft, with
the camshaft in the TDC position (ie with the
inlet camshaft sprocket timing mark in line
with the top edge of the cylinder head,
pointing to the inlet side of the engine - see
paragraph 4). Again, turn the camshaft if
necessary to enable the sprocket to be fitted.
41With the sprocket fitted, fit the distributor
rotor shaft to the end of the camshaft, and
tighten the securing bolt finger-tight. Note that
it is acceptable for the timing chain to sag
slightly between the two pulleys.
DOHC engine 2B•13
2B
18.30b Camshaft oil spray bars correctly
fitted
18.38 Spacer and sprocket securing bolt
fitted to end of camshaft, with camshaft in
TDC position (timing marks arrowed)
18.34 Timing chain tensioner plunger
assembly
A Piston retracted - plunger assembly
useable
B Piston partially unlatched - discard plunger
assembly
C Latching ring (1) visible - discard plunger
assembly
18.30c Fitting the timing chain guide plate
18.30a Camshaft bearing cap tightening
sequence (see text)18.26 Use new M8 (auxiliary) cylinder head
bolts with hexagonal heads (A), not earlier-
type Torx bolts (B)
Warning: Take care when
installing the plunger assembly,
as there is a risk of injury if the
piston flies out.