1980 FIAT 127 lock

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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)

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3.68 Fitting the distributor



3.70 Distributor clamp bolt


extension length and the torque wrench length
and is calculated by using the formula:

where A is the specified torque loading (Ibf ft or
kgf m), B is the torque to be set, or read, when
using an extension (Ibf ft or kgf m), y is the
length of extension (ft or m), and z is the length
of torque wrench (ft or m).
Example: Specified torque is 60 Ibf ft, length of
extension is 6 in, and length of torque wrench is
2 ft, then B = (60 x 2) = (6/12 + 2) = 120 =2'/z =
48 Ibf ft; torque wrench setting or indication.
When measuring, use centres of bolts/nuts and
centre of torque wrench drive square. When
calculating, keep values constant, that is, don't
mix inches and feet for example (photos). 63 Fit
the drivebelt as described later in this Section.
When fitted, the auxiliary shaft pulley bolt and
the camshaft pulley bolt can be torque loaded to
the specified settings if these were not done on
assembly.
Distributor - refitting
64 The distributor is mounted nearly vertical on
the oil filter side of the engine and is driven by
skew gears from the auxiliary shaft. In turn the
distributor shaft also drives the oil pump through
a splined coupling (photo).
65 It is more convenient to set the contact
breaker gap before fitting the distributor to the
engine. Adjust to the specified clearance
(photo).
66 Turn the crankshaft in the normal direction of
rotation until the line on the crankshaft pulley is
adjacent to the first of the three pointers on the
timing bracket. This is 100 BTDC, the second
pointer is 50 BTDC and the large, third pointer is
TDC. Note which cylinder, either 1 or 4, is on the
compression stroke. This is indicated by both of
the inlet and exhaust cams pointing upwards
causing their relative valves to be shut. 67
Rotate the distributor shaft until the rotor is
opposite the terminal in the distributor cap
serving the same cylinder number as the one
which was on compression stroke and with the
contact breaker points just breaking.
68 Lubricate the distributor skew gear with clean
engine oil and insert the distributor into the
engine block. Watch the rotor carefully to see
how much it turns as the skew gears mesh.
Then withdraw the distributor, reset the rotor and
then preset it the same amount that it turne d


3.77 Fitting the toothed drivebelt-crankshaft V-bel t pulley
removed for clarity

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3.60 The cylinder head gasket is fitted ALTO upward s 3.61 Lower the cylinder head onto the block



3.62A Tighten the cylinder head bolts and nuts to t he
specified torque 3.62B These cylinder head nuts might be difficult
to torque
tighten


3.64 Distributor driveshaft skew gear 3.65 Checkin g the contact breaker gap

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altering the throttle speed screw.
16 On earlier carburettors, or if new components
have been fitted to carburettors having a
tamperproof screw, then the slow-running and
mixture can be altered, but only if an exhaust
gas analyser is available in the case of later
carburettors, after the tamperproof cap has been
broken off.
17 On earlier units, use a device such as a
mixture adjustment aid or a vacuum gauge fitted
in accordance with the manufacturers'
instructions to obtain the correct slow-running
adjustment.
18 On later units, an exhaust gas analyser,
again used in accordance with the maker's
instructions, will ensure that the CO level is
within the limits specified. Fit a new tamperproof
cap on completion.
Weber dual venturi carburettor

Removal and refitting
19 These operations are similar to the
operations described in paragraphs 3 to 9 of this
Section, but the unit is of manually operated
choke design and will therefore not have coolant
hose attachments. A choke cable is fitted
instead.
Dismantling and adjustment
20 The operations are similar to those described
for the single venturi type carburettor, once the
upper body has been removed (six screws).
21 If jets are extracted, identify them as to which
side of the carburettor (primary or secondary)
they came from.


4.4 Throttle cable connection to Weber single ventu ri
carburettor 4.5 Weber single venturi carburettor installed (va
cuum pipe
arrowed


4.7 Weber single venturi carburettor showing coolan t hoses
(arrowed) to automatic choke housing. Note fuel hos es
connected to top right of carburettor 7.6 Location of fuse block - 1049 cc engine models