engine oil FIAT 127 1976 1.G Workshop Manual

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Supplement

Contents

Introduction ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 1

Specifications ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 2

Engine … … … ... ... ... ... ... ... ... ... ... . .. ... ... ... ... ... ... ... ... ... ... ... 3
1049 cc engine - general
Crankshaft - refitting
Piston rings - refitting
Pistons and connecting rods - reassembly
Pistons - refitting
Connecting rods to crankshaft - reassembly
Oil pump - reassembly
Crankshaft oil seals and carriers - refitting
Sump - refitting
Auxiliary shaft and seal - refitting
Belt - pulleys and tensioner - refitting
Cylinder head and valve gear - reassembly
Distributor - refitting
Toothed drive belt - removal, refitting and adjust ing
Valve clearances - adjustment
Engine - final assembly
Engine removal – 127 Special and 127 from chassis number 1104290 onwards

Fuel system ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 4
Carburettors - general
Weber or Solex single venturi carburettors
Weber dual venturi carburettor
Carburettor overhaul - general

Ignition system... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 5
Automatic centrifugal advance curves
Braking system... ... ... ... ... ... ... ... ... . .. ... ... ... ... ... ... ... ... ... ... ... 6
Brake fluid reservoir and vacuum servo unit (Sport )

Electrical system... ... ... ... ... ... ... ... .. . ... ... ... ... ... ... ... ... ... ... ... . 7
Charging system
Fuses (127 Special)
Fuses (1049 cc models)
Bodywork and fittings ... ... ... ... ... ... ... . .. ... ... ... ... ... ... ... ... ... ... 8
Model variations
Wing mouldings and front spoiler (Sport) - removal and refitting
Rear spoiler (Sport) – removal and refitting

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2. Specifications

Capacities (1049 cc models )
Engine oil (including filter change)
L, C and CL ... ... ... ... ... ... ... ... … 5.5 pints (3.1 litres)
Sport ... ... ... ... ... ... ... ... ... 7.7 pi nts (4.4 litres)

Coolant ... ... ... ... ... ... ... ... … 9.7 pints (5.5 litres)

Fuel ... ... ... ... ... ... ... ... … 6.7 gallons (30 .5 litres) including 6.2 pints
(3.5 litres) reserve

Transmission oil ... … ... ... ... ... ... ... . 4.2 pints (2.4 l itres)


1049 cc OHC engine
General
Type number ... ... ... ... ... ... ... ... … 127 A 000 (C, L and CL);
127 A1.000 (Sport)
Bore ... ... ... ... ... ... ... ... … 2.992 in (76 mm)
Stroke ... ... ... ... ... ... ... ... ... 2.276 in (57.8 mm)
Capacity ... ... ... ... ... ... ... ... … 64 cu in (1049 cc)
Compression ratio ... ... ... ... ... … 9,3 : 1 (C, L and CL);
9,8 : 1 (Sport)
Maximum horsepower (DIN) ... ... ... ... 50 HP a t 5600 rpm (C, L and CL);
70 HP at 5600 rpm (Sport)

Valve mechanism C, L and CL Sport
Inlet :
Opens ... ... ... ... ... ... ... ... ... 2° B TDC 6° BTDC
Closes ... ... ... ... ... ... ... ... ... 42° ABDC 46°ABDC
Exhaust :
Opens ... ... ... ... ... ... ... ... ... 42° BBDC 47° BBDC
Closes ... ... ... ... ... ... ... … … 2° ATDC 7° ATDC
Valve clearances (cold) :
For checking valve timing:
Inlet ... ... ... ... ... ... ... ... 0.02 8 in (0.70 mm) 0.032 in (0.80 mm)
Exhaust ... ... ... ... ... ... ... 0.028 in (0.70 mm) 0.032 in (0.80 mm)
Adjustment for running (engine cold) :
Inlet ... ... ... ... ... ... ... ... 0.01 2 in (0.30 mm) 0.016 in (0.40 mm)
Exhaust ... ... ... ... ... ... ... 0.016 i n (0 40 mm) 0.020 in (0.50 mm)

Cylinder block and connecting rods inches mm
Cylinder bore diameter * 2.992 to 2.994 76.00 to 7 6.05
* Cylinder bores are graded and have a variation of 0.0004 inch (0.01 mm) between each grade
Main bearing housing bore diameter 2.044 to 2.045 51.921 to 51.934
Width of centre main bearing cap between

thrust washers 1.088 to 1.091 27.64 to 27.70
Connecting rod big-end diameter 1.85 to 1.8560 47. 130 to 47.142
Connecting rod small-end diameter 0.8638 to 0.8646 21.94 to 21.96
Big-end bearing shell thickness 0.0606 to 0.8646 1. 539 to 1.55

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Camshaft bearing bore diameter in head:
Valve gear end 1.1807 to 1.1817 29.990 to 30.015
Centre 1.0648 to 1.0657 27.045 to 27.070
Flywheel end 0.9860 to 0.9870 25.045 to 25.070
Camshaft journals fit clearance 0.0012 to 0.0028 0. 030 to 0.070
Cam lift (C, L and CL) 0.3425 8.700
Cam lift (Sport):
Inlet 0.3622 9.200
Exhaust 0.3642 9.250
Standard tappet bore diameter 1.4567 to 1.4577 37.0 00 to 37.025
Standard tappet outside diameter 1.4557 to 1.4565 36.975 to 36.995
Tappet fit clearance 0.0002 to 0.0020 0.005 to 0.05 0
Shim thickness 0.1279; 0.1299; then
0.0039 steps to 0.1850

3.2b; 3.30; then
0.10 steps to 4.70

Auxiliary shaft inches mm
Diameter of bush bores in crankcase:
Front 1.6339 to 1.6350 41.500 to 41.530
Rear 1.5733 to 1.5745 39.962 to 39.992
Fitted bush internal diameter:
Front 1.5143 to 1.5151 38.464 to 38.484
Rear 1.4553 to 1.4561 36.964 to 36.984
Diameter of shaft journals:
Front 1.5115 to 1.5125 38.393 to 38.418
Rear 1.4525 to 1.4535 36.893 to 36.918
Bush fit There must always be an interference fit
Shaft/bush fit clearance (front and rear) 0.0018 to 0.0036 0.046 to 0.091
Lubrication system
Oil pump Four lobe rotor type
Pump drive Through auxiliary shaft
Oil pressure relief valve Incorporated in pu mp
Pump rotors endfloat 0.0018 to 0.0047 0.045 to 0.120
Outer rotor to body clearance 0.0006 to 0.002 2 0.016 to 0.055
Inner to outer rotor clearance 0.0010 to 0.00 39 0.025 to 0.100
Oil pressure at 212°F (100°C) 50 to 70 Ibf/in
2 (3.5 to 5 kgf/cm2)

Cooling system
Radiator fan thermal switch
Cuts in . 194° to 201°F (90° to 94°C)
Cuts out 185° to 192°F (85° to 89°C)
Engine coolant thermostat
Starts to open 176° to 183°F (80° to 84°C)
Fully open 205°F (96°C)
Impellor vanes to pump body fit clearance 0.0315 to 0.0512 in (0.8 to 1.3 mm)

Radiator cap relief pressure 11.4 Ibf/in
2 (0.8 kgf/cm2)

Fuel system
Weber 32 ICEV 16/150 carburettor (C, L and CL model s)
Venturi diameter 0.8465 in (21.5 mm)
Main jet . 0.0453 in (1.15 mm)

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Lamps
Headlamps (C, L and CL)
Headlamps (Sport)
Brake and rear light
Turn indicators
Reversing lights
Parking lights
Number plate
Courtesy light
Boot light
Turn repeaters
Cigar lighter light
Instrument panel
Ignition warning
Turn indicator warning
Headlamp warning
Coolant temperature warning (L models)
Oil pressure warning
Fuel warning
Hazard warning
Sidelamp (out) warning (Sport only)
Brake warning (Sport only)
Heated rear window warning (Sport only)
40/45 watts
55/60 watts (Halogen)
5/21 watts
21 watts
21 watts
5 watts
5 watts
5 watts
5 watts
4 watts
4 watts
3 watts
3 watts
1.2 watts
1.2 watts
1.2 watts
1.2 watts
1.2 watts
1.2 watts
3 watts
1.2 watts
1.2 watts

Fuses
For fuse details (127 Special, L, C, CL and Sport) see Sections 23 or 24

Steering and suspension (Sport only)
Steering angles
Inner wheel 34° 50’
Outer wheel 32° 10’
Front wheel alignment (toe setting)
Laden 0.079 in (2.0 mm) toe-in to 0.079 in (2.0 mm) toe-o ut
Unladen 0.138 in (3.5 mm) to 0.217 in (5.5 mm) toe-in

Roadwheels
Size 4½ B x 13
Tyres 135 SR-13 or 155/70 SR-13

All 1049 cc models Ibf ft kgf m
Main bearing cap bolts 59 8.2
Engine mounting securing bolts 43 6
Cylinder head to block bolts and nuts:
1 st stage 30 4.1
2nd stage 45 6.2
Final stage 61 8.5
Manifold to head nuts 20 2.8
Connecting rod big-end nuts 38 5.2
Flywheel to crankshaft bolts 61 8.5
Driven gear (Plastic) to camshaft retaining bolt 87 12
Driven gear (steel) to camshaft retaining bolt 87 1 2
Camshaft cap nuts 14 2

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Ignition distributor clamp nut 11 1.5
Oil pump to crankcase bolts 13 1.8
Cylinder head outlet pipe bolt 16 2.2
Water pump/alternator drive pulley nut 101 14
Alternator bracket to crankcase bolt 20 2.8
Alternator to lower bracket bolt 36 5
Cylinder head upper bracket bolt 20 2.8
Alternator to upper bracket nut 36 5
Upper bracket securing bolt 13 1.8
Oil pressure switch 24 3.3
Coolant temperature switch 36 5
Spark plug 27 3.8

Sport models only
Engine
Flexible mounting to body (engine side) 65 9.0
Flexible mounting support (engine side to body)
18 2.5
Flexible mounting upper support to gearbox 18 2.5
Engine crossmember to body 18 2.5
Flexible mounting support nut (gearbox side) 18 2.5
Flexible mounting support bolt to body
(gearbox LH side) 65 9.0
Steering and suspension
Steering wheel retaining nut 22 3.0
Front wheel bearing ring nut 44 6.0
Front wheel hub nut 160 22.0
Roadwheel bolts 64 8.8
Front suspension track control arm to body 20 2.7
Front suspension balljoint to hub carrier 40 5.5
Rear wheel hub nut 160 22
Transmission
Starter motor bolt to bellhousing lower support 18 2.5
Gear selector shaft nut 18 2.5
Upper gear lever relay lever 22 3.0
Idler support securing nut 18 2.5
Differential case flange to gearbox housing 18 2.5

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3. Engine

1049 cc engine - general
1 This engine is of overhead camshaft design,
using shims for valve clearance adjustment. The
crankshaft is supported in five main bearings,
the centre one incorporating the thrust washers
which control crankshaft endfloat.
2 An auxiliary shaft, driven by the toothed
camshaft belt, is used to drive the distributor and
the fuel pump. 3 Most major engine components
can be removed while the engine is in the car,
but operations on the crankshaft, main bearings
and flywheel can only be carried out after the
engine has been removed.
4 Engine removal and subsequent dismantling
follows closely the information given for the
overhead valve engine in Chapter 1, but the
following sequence for complete engine
dismantling is recommended:
(a) Engine ancillaries (alternator, fuel pump, distributor)
(b) Timing belt cover
(c) Water pump
(d) Timing belt tensioner and belt
(e) Manifolds
(f) Cylinder head complete with camshaft
(g) Crankshaft pulley
(h) Auxiliary shaft sprocket
(i) Sump
(j) Oil pump and auxiliary shaft
(k) Connecting rods and pistons
(l) Flywheel and crankshaft oil seal carriers
(m) Crankshaft and main bearings

5 If the cylinder head is to be dismantled, before

withdrawing the camshaft, have a suitably divided
container ready so that the valve clearance
adjusting shims can be extracted and kept in strict
originally installed order together with their
appropriate valves, springs etc.
6 All engine parts must be thoroughly cleaned
and examined as explained in Chapter 1. Where
required, all defective parts should be renewed
before reassembly starts.
Crankshaft – refitting
7 Fit the main bearing shells to their seats in the
crankcase after making sure that both shells and
seats are spotlessly clean and dry (photos).
8 With a light smear of grease, fit the two half
thrust washers each side of the centre bearing
with the oil grooves in each washer facing away
from the bearing shell (photo).
9 Using clean engine oil lubricate the bearing
shells and crankshaft main bearing journals
(photo).
10 Carefully lower the crankshaft into its bearings
in the crankcase after making sure that it is the
right way round. Spin the shaft to distribute the o il
(photo).
11 Fit the clean and dry bearing shells to the main
bearing caps. Oil the bearing face and fit the
bearing caps to the crankcase. Make sure that
each cap is fitted to its own location by checking
the groove marks in the base, and that each cap
is the right way round. This is achieved when the
axial locating tags in each half bearing shell butt
on the same side (photos).



3.7A Thoroughly clean the bearing shells and seats
before
assembly 3.7B Note that central bearing shell has no oil gro ove but all
shell are axially located by an offset tag

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3.8 The half thrust washers are fitted each side of
the
centre bearing


3.9 Oil the bearings and crankshaft journals…





3.10 … and then fit the crankshaft into the crankca se 12 Refit the main bearing cap bolts and screw
them up fingertight. Spin the crankshaft and, if
all is well, tighten the bolts to the specified
torque load and turn the crankshaft again to
check freedom of rotation (photo).
13 Measure the crankshaft endfloat with feeler
gauges. If this exceeds the specified tolerance,
oversize thrust washers will have to be fitted.
Pision rings - refitting
14 Follow the procedure given in Chapter 1,
Section 42.
Pistons and connecting rods–reassembly
15 Follow the procedure given in Chapter 1,
Section 43 (photo).
Pistons – refitting
16 Follow the procedure given in Chapter 1,
Section 44.
17 Note that the connecting rods in the 1049 cc
engine have two oil jet holes leading from the
big-end bearing (photo).
18 When the piston is correctly fitted it will have

the valve depressions adjacent to the side of the
block with the cylinder head studs in (photo). C
onnecting rods to crankshaft-
r
eassembly
19 Follow the procedure given in Chapter 1,
Section 45.
20 Torque load the big-end cap nuts to the
reading quoted in the Specifications of this
Chapter 13 - it is different from the value quoted
for the 903 cc engine (photo).
Oil pump - reassembly
21 The oil pump fitted to the 1049 cc engine is a
Hobourn-Eaton rotor type of pump which is quite
different from the gear pump fitted to the 903 cc
engine. It consists of a four lobed rotor rotating
in a five slotted outer rotor which is mounted
eccentrically to the inner rotor. As the inner roto r
rotates the outer rotor is driven round, and the
spaces between the lobes on the inner rotor and
the slots in the outer rotor increase and
decrease once per revolution. The increasing
spaces are connected to the pump inlet and
cause oil to be drawn into the pump. The
decreasing spaces connect with the pump outlet
through which the oil is forced to feed the
engine. A springloaded relief valve in the outlet
of the pump vents excessive oil pressure into
the sump. The efficiency of the pump depends

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3.32 Fitting the crankshaft seal and carrier at fly wheel
and… 3.33 …and at the timing cover end



3.34 The timing indicator bracket is located behind the two
top bolts of the seal carrier 3.36 Fit the sump to the crankcase

on fine clearances and these should be checked
during assembly.
22 Fit the outer rotor to the pump body and then
fit the inner rotor (photos).
23 Lay an accurate straight edge across the
faces of the rotors and pump body and measure
the clearance with feeler gauges (photo).
24 Insert a feeler gauge between the outer rotor
and the pump body to measure the clearance
(photo).
25 Similarly insert a feeler gauge between the
inner rotor lobe tip and the outer rotor to
measure the clearance between the two (photo).

26 Compare the clearances with the tolerances
quoted in the Specifications to this Chapter. Any
excessive clearance could result in low oil
pressure, and as the inner and outer rotors are
matched pairs the only solution is a new or
reconditioned pump assembly. 27 Fit the oil pressure relief valve plunger to th
e
pump body followed in turn by the spring,
retainer plate and circlip (photos).
28 Lubricate the rotors with clean engine oil and
refit the pump lower half body and strainer
(photo).
29 With a new gasket, fit the assembled oil
pump to the crankcase block and secure with
the two long bolts (photo). Tighten to the
specified torque load.
30 Fit the oil tube to the crankcase securing it by
its bracket to the centre main bearing cap with
its retaining bolt. Tighten to the specified torque
load (photo).
Craknshaft oil seals and carriers-refitting
31 Clean the flywheel mounting spigot on the
end of the crankshaft and lubricate the
crankshaft seal with clean engine oil. Fit a new
gasket.

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32 Carefully ease the lip of the seal onto the
spigot and secure the carrier with the bolts and
washers (photo).
33 Similarly clean the crankshaft at the timing
belt end and fit the seal and carrier. Retain by
the two bottom bolts (photo). 34 Put the timing
indicator bracket over the two top bolt holes in
the seal carrier and fit the two top bolts (photo).

Sump - refitting
35 Make sure that there are no remnants of the
old gasket on the sump flange and fit a new
gasket using a little grease to hold it in position .
Check that it is bedded down evenly all round
the flange.
36 Fit the sump to the crankcase. Put the load
spreading washers on each bolt and screw into
the crankcase (photo).
37 Tighten the bolts evenly to avoid warping the
flange.
Auxiliary shaft and seal - refitting
38 Clean the auxiliary shaft bearings and
lubricate with clean engine oil.
39 Insert the shaft into the crankcase bushes
and rotate the shaft to spread the oil (photo).
40 Lubricate the auxiliary shaft seal in its carrie r
and carefully ease the seal over the shaft spigot
(photo).
41 Fit the seal carrier retaining bolts and
washers and tighten.
Belt pulleys and tensioner - refitting
42 Fit the toothed pulley to the auxiliary shaft.
The recess in the pulley fits on the auxiliary shaf t
with the dowel on the shaft in the hole in the
pulley (photo). Fit the retaining bolt and washer
and partially tighten, as it will be necessary to
wait until the drivebelt has been fitted before
finally tightening this bolt. Alternatively, it is
possible to hold the auxiliary shaft carefully in a
vice, fit the seal and carrier to the shaft, follow ed
by the toothed pulley and its retaining bolt and
washer, and then tighten the bolt fully before
fitting the complete assembly to the block.
43 The belt tensioner bracket can now be fitted.
Clean off all traces of old gasket from the
bracket and block and use a new gasket on
assembly. Fit the retaining bolts and washers
and tighten (photo).
44 Insert the spring-loaded plunger assembly
into the tensioner bracket (photo).
45 The tensioning wheel in its carrier can now
be fitted. Put the top bolt and washer in first and
then bear down to compress the spring and fit the bottom bolt through the kidney-shaped slot.
Note that this latter bolt has an additional, large
washer against the wheel carrier. Temporarily
tighten the two bolts they will have to be
retightened after the belt has been fitted (photo).

46 If the key had previously been removed from
the pulley end of the crankshaft, clean the key
slot and refit the key. Then slide on the bevelled
washer, making sure that the bevel is on the
side away from the crankcase (photo).
47 Refit the crankshaft toothed pulley (photo).
Then the V-belt pulley can be refitted together
with its retaining nut and washer. Final
tightening of this nut can wait until the flywheel
has been fitted, when a 'gag' can be fitted to the
flywheel to hold the crankshaft whilst tightening
the nut - see Chapter 1, photo 23.2A.

Cylinder head and valve gear-reassembly

48 It is assumed that the valves will have
already been examined and renovated as
described in Chapter 1, Section 31. Follow the
procedure given in Chapter 1, Section 51 to
reassemble the valves, but note that new oil
seals should be fitted to this engine when the
valves have been inserted in the guides and
before the springs are fitted (photos).
49 Each tappet bucket contains a shim in the
head which is used to control the valve
clearance. Before assembling the buckets to
their valves, prise out each shim and take a note
of the thickness. This is etched on the lower face
of the shim and indicates the thickness in
millimetres to two decimal places. If the number
has worn off, use a micrometer to check the
shim thickness. Make a table showing each
valve by number and the thickness of shim on
assembly. Reassemble each shim to its bucket
and after lubricating with clean engine oil fit the
buckets to their respective valves (photos).
50 Lubricate the two camshaft bearings in the
cylinder head and carefully thread the camshaft
through the driving end hole and lower it onto its
bearings. The cams will rest on the tappet
buckets and the camshaft should now be turned
so that the two cams over No. 1 cylinder (driving
end) are pointing upwards (compression/firing
stroke). This is to reduce the bending load on
the camshaft as the two bearing halves are
being tightened down (photo).
51 Lubricate the camshaft bearing halves and fit
them to their respective studs in the head. Put
the steel bridge plates in position and fit the
washers and nuts (photo).
52 Tighten the four nuts a little at a time

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progressively until the bearing halves meet.
53 Oil the camshaft seal and carefully fit it with
its carrier and a new gasket to the cylinder head
(photo).
54 Position the drivebelt guard backplate over
the camshaft seal carrier and fit the three bolts
and washers (photo). 55 Tighten the three bolts
retaining the backplate and seal carrier. Torque
load the four camshaft bearing securing nuts to
the specified setting.
56 Fit the camshaft toothed driving pulley with its
bolt and washer. Leave the final tightening until
the drivebelt is fitted (photo).
57 Check the valve clearances; the camshaft
can be turned by a spanner on the pulley
retaining bolt. Readjust any clearance if
necessary, as described later in this Section.
58 Owing to the small clearance between a
piston at TDC and the open valves during
exhaust/inlet overlap, it is imperative to get the
crankshaft and camshaft in their correct related
positions before turning the engine after fitting
the cylinder head. If this relationship is out then
serious damage could be done to the valves or
pistons by turning the crankshaft, as the pistons
will impinge on the valve heads. To avoid this
the following sequence should be observed. Set
the crankshaft as described in paragraph 59,
and the camshaft (before assembling the
cylinder head to the block) also as described in
paragraph 59. Fit the head to the block taking
care not to disturb the set positions and, finally,
fit the toothed drivebelt. Then the crankshaft can
be turned with no likelihood of damage.
59 Set the crankshaft by using a spanner on the
pulley retaining nut and aligning the mark on the
pulley with the long pointer on the timing
indicator bracket. Then set the camshaft by
aligning the hole in the camshaft pulley with the
cast ridge on the top of the camshaft seal carrier
just behind the toothed pulley (photo).
60 Fit a new cylinder head gasket with the word
ALTO upwards (photo). Do not use grease or
any other jointing compound. 61 Taking care not
to disturb the crankshaft or camshaft lower the
cylinder head onto the block (photo).
62 Fit the thick washers to the studs on the
manifold side of the block followed by the nuts.
Fit the bolts with their thick washers to the other
side of the block and screw the bolts and nuts
down to lightly compress the gasket. The bolts
and nuts must now be torque loaded by stages
(see Specifications) in sequence, to the
specified load and in the order shown in
Fig.13.3. This may present some difficulty as,
owing to the shape of the cylinder head, it is not
possible to get a socket spanner fitted to a
torque wrench over the cylinder head nuts.
These can be tightened using a ring or open-
ended spanner as an extension to the torque
wrench, but then, of course, the applied torque
will be different to the torque registered or set o n
the torque wrench. To overcome this a simple
calculation can be made so that a setting can be
established for the torque wrench which, with an
extension, will produce the specified torque
loading. This value varies with the ratio of t he


Fig. 13.3. 1049 cc engine cylinder head nut and bol t tightening sequence (Sec.3)