FIAT Uno 45 - Manual (Page 155)

crankcase. If the shells are to be used again,
keep them with their respective bearing caps.
70 The thrust washers which control
crankshaft endfloat are located in the
crankcase, and retained by the turned-over
edges of the centre main bearing shell.
71 The engine is now fully stripped.
Examination and renovation
72 The procedures for the following items are
essentially as described in Chapter 1, Sec-
tion 18.
Cylinder block and crankcase
Crankshaft and bearings
Flywheel
Oil seals and gaskets
Cylinder head
73 Using a straight-edge, check the cylinder
head gasket surface for distortion. If it
exceeds the specified tolerance, it must be
surface ground by your dealer.
74 Refer to Chapter 1, Section 39, for
dismantling and renovation operations. Note
that single valve springs are fitted.
Oil pump
75 Checking operations are described in
sub-Section B.
Pistons and connecting rods
76 Refer to sub-Section B.
77 If one or more connecting rods are
changed, it is important that its weight is
identical to that of the original. Use an
accurate balance to weigh them and remove
metal if necessary from the new rod in the
areas indicated in Fig. 13.7.
Camshaft and cam followers
78 If the camshaft journals or bearings show
any sign of wear or scoring, then the
camshaft, or cylinder head, or both must be
renewed.
79 The cam followers should be checked for
ovality using a micrometer. Unless unworn
they should be renewed.
Timing belt tensioner and timing belt
80 The tensioner is a lubricant-sealed pulley,
and it should be tested for smooth and quiet
operation by turning it with the fingers. Any
evidence of roughness or rattle will indicate
the need for a new assembly (photo).
81 The timing belt should be inspected at
regular intervals for correct adjustment and
condition (see Section 3 or “Routine
maintenance”
at the beginning of the Manual).
If there is evidence of worn teeth, cracking or
fraying, or oil contamination, renew the belt.
The vehicle manufacturers recommend that
the belt is renewed whenever it is removed,
and it should certainly be renewed at the
intervals specified in Section 3 or the main
“Routine maintenance” section at the
beginning of this Manual as a precautionary
measure against belt breakage and
consequent expensive engine damage.
PART D:
ENGINE REASSEMBLY AND
REFITTING
Reassembly - general
1 Refer to Chapter 1, Section 19.
Complete reassembly
#
2 With the cylinder block/crankcase standing
on the work surface, fit the bearing half shells
into their crankcase seats (photo). Make sure
that the seats are perfectly clean as dirt or grit
trapped under the shell will cause binding
when the crankshaft is turned.
3 The centre bearing crankcase web
incorporates the thrust washers held by the
lips of the bearing shell (photo).
4 Oil the shells and lower the crankshaft into
the crankcase (photo).
5 Fit the bearing shells into the main bearing
caps, again making sure that the shell seats
are perfectly clean (photo).
13•30 Supplement: Revisions and information on later models
5D.5 Main bearing cap and shell 5D.4 Fitting the crankshaft
5D.3 Crankshaft thrust washer at centre
bearing
5D.2 Main bearing shell in crankcase
Fig. 13.8 Checking a cam follower for
ovality - 999 and 1108 cc engine (Sec 5C)
Fig. 13.7 Metal removing areas (arrowed)
on connecting rod - 999 and 1108 cc
engine (Sec 5C)
5C.80 Timing belt tensioner