engine oil FIAT 127 1977 1.G User Guide

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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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78 Slacken the tensioner bolts to tension the belt
and retighten the bolts (photo).
79 Turn the engine over for two complete
revolutions to even out belt tension. Then again
slacken the tensioner bolts to let the tensioner
take up any slack and
retighten the bolts. Never
turn the engine backwards or rock the camshaft
when tensioning the belt, as slack could develop
in the belt and it might jump a tooth.
80 Refit and tension the alternator/water pump
V-belt. Refit the drivebelt cover.
Valve clearances - adjustment
81 Checking the valve clearances should be
done at the 6000 miles servicing, or whenever
the cylinder head has been removed and
refitted for any reason. It is important that the
clearances are set correctly, otherwise the
timing will be wrong and the engine
performance will be poor. If there is no
clearance at all, the valves and seats will soon
get burnt. Set the clearances with the engine
cold.
82 Remove the camshaft cover. The engine can
be turned over by either using a spanner on the
crankshaft pulley nut, or by jacking up a front
wheel, engaging top gear and using the wheel
to turn the engine.
83 Each tappet must be checked when its
operating cam is pointing upwards, 1800 away
from the tappet. Check the clearances in the
firing order, No. 1 cylinder first and then 3, 4
and 2. Do the exhaust of one cylinder and the
inlet of the one after, at the same time to
minimise the amount of engine turning. Counting
from the timing belt end, exhaust valves are
1-4-5-8, inlet valves 2-3-6-7.
84 Insert the feeler gauge for the appropriate
valve. See the Specifications for correct
settings. The feeler should slide in readily
between cam and shim, but with slight frictional
drag. Try one a size thicker and one a size
thinner. The thick one should not go in and the
thinner one should be too loose (photo).
85 If the clearance is wrong, measure the
clearance and write it down with the number of
the valve. When all the clearances have been
checked, it will be necessary to remove those
shims which are fitted where the clearances are
wrong, and renew them with different thickness
shims. If a clearance is too big, use a thicker
shim. If a clearance is too small use a thinner
shim. Calculate by simple subtraction. 86 To change a shim, turn the engine until the
relevant cam is pointing upwards, then turn the
tappet in its housing so that the slot in the rim is
accessible.
87 The manufacturer provides special tools for
depressing tappets (Nos. A60480 and A60443).
These make the job easier if they can be
borrowed, but it is possible to do the job without
them. The best way is to make up a tool from a
piece of steel plate shaped as shown in the
photograph. Alternatively use a screwdriver to
lever the tappet down and another on
e, on edge,
to hold the tappet down by positioning it
between the camshaft and the rim of the tappet;
then remove the lever. This is quite tricky and
needs some care to avoid any damage. If in any
doubt about doing this job it should be left to a
FIAT agent. As well as having the right tools he
will also have a stock of shims from which to
choose those required to correct wrong
clearances. It is expensive buying shims that are
not required (photo).
88 With the tappet held down, prise the shim out
with a thin screwdriver. The FIAT way is to lift
the shim using compressed air, which is
effective if an air line is available. The shims are
held in quite strongly by the oil film and they
must be lifted up square or they will jam.
Remove the shim with long-nosed pliers
(photos).
89 When new, shims have their thickness
marked in millimetres on their undersides. This
marking may wear off and then it will be
necessary to measure their thickness with a
micrometer. From the thickness of the shim and
the error in the clearance, calculate the size of
shim required to produce the correct clearance.
90 Insert the new shim, numbered side down
towards the tappet. Remove the tools used for
depressing the tappet and repeat the operation
until all clearances are correct.
91 Using clean engine oil lubricate all moving
and sliding parts in the camshaft/tappet
assembly. Fit a new gasket and refit the
camshaft cover together with the nine bolts and
washers. Tighten the bolts progressively (photo).


Engine - final assembly
92 Completing assembly of the 1049 cc engine
follows broadly the procedure for that of the
smaller engine which is dealt with in Chapter 1,
Section 56.
93 The manifold gasket is supplied in two parts
for the 1049 cc engine (photo). These serve