Iveco Stralis AT/AD. Manual - part 47

73535

Figure 102

Figure 103

Check the bushing in the small end has not come loose and
shows no sign of scoring or seizure; replace it if it does.
The bushing (2) is removed and fitted with a suitable drift (1).
When driving it in, make absolutely sure that the holes for the
oil to pass through in the bushing and small end coincide.
Using a boring machine, rebore the bushing so as to obtain
a diameter of 50.019 — 50.035.

Checking connecting rods

61696

Checking axis alignment
Check the alignment of the axes of the connecting rods (1)
with device 99395363 (5), proceeding as follows:
Fit the connecting rod (1) on the spindle of the tool 99395363
(5) and lock it with the screw (4).
Set the spindle (3) on the V-prisms, resting the connecting rod
(1) on the stop bar (2).

Check the torsion of the connecting rod (5) by comparing
two points (A and B) of the pin (3) on the horizontal plane
of the axis of the connecting rod.
Position the mount (1) of the dial gauge (2) so that this
pre-loads by approx. 0.5 mm on the pin (3) at point A and
zero the dial gauge (2). Shift the spindle (4) with the
connecting rod (5) and compare any deviation on the
opposite side B of the pin (3): the difference between A and
B must be no greater than 0.08 mm.

Figure 104

61694

Check the bending of the connecting rod (5) by comparing
two points C and D of the pin (3) on the vertical plane of the
axis of the connecting rod.
Position the vertical mount (1) of the dial gauge (2) so that
this rests on the pin (3) at point C.
Swing the connecting rod backwards and forwards seeking
the highest position of the pin and in this condition zero the
dial gauge (2).
Shift the spindle (4) with the connecting rod (5) and repeat
the check on the highest point on the opposite side D of the
pin (3). The difference between point C and point D must be
no greater than 0.08 mm.

Figure 105

Checking bending

TRALIS

AT/AD

174

F3A ENGINE

Base - January 2003

Bushings

73536

74052

60614

Figure 106

Figure 107

Figure 108

The piston (1) has to be fitted on the connecting rod (2) so
that the graphic symbol (4), showing the assembly position
in the cylinder liner, and the punch marks (3) on the
connecting rod are observed as shown in the figure.

Fit the pin (2) and fasten it on the piston (1) with the split rings
(3).

To fit the piston rings (1) on the piston (2) use the pliers
99360184 (3).
The rings need to be mounted with the word ”TOP” (4)
facing upwards. Direct the ring openings so they are
staggered 120

° apart.

Mounting the piston rings

49030

Fit the bearing shells (1), selected as described under the
heading ”Selecting the main and big end bearing shells”, on
both the connecting rod and the cap.

If reusing bearing shells that have been removed, fit them
back into their respective seats in the positions marked
during removal.

Figure 109

Fitting the big end bearing shells

175

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F3A ENGINE

Mounting the connecting rod — piston assembly

60615

Fitting connecting rod - piston assemblies
in the cylinder liners

With the aid of the clamp 99360605 (1, Figure 110), fit the
connecting rod — piston assembly (2) in the cylinder liners,
according to the diagram of Figure 111, checking that:

- The openings of the piston rings are staggered 120

° apart.

- The pistons are all of the same class, A or B.

- The symbol punched on the top of the pistons faces the

engine flywheel, or the recess in the skirt of the pistons
tallies with the oil nozzles.

60616

Figure 110

Figure 111

The pistons are supplied as spares in class A and can
be fitted in class B cylinder liners.

ASSEMBLY DIAGRAM OF CONNECTING ROD — PISTON ASSEMBLY IN CYLINDER LINER

1. Connecting rod — piston assembly — 2. Area of punch marking on the top of the piston,

symbol showing assembly position and selection class — 3. Connecting rod punch mark area

Checking piston protrusion

On completing assembly, check the protrusion of the pistons
from the cylinder liners; it must be 0.23 — 0.53 mm.

TRALIS

AT/AD

176

F3A ENGINE

Base - January 2003

Mount the connecting rod caps (1) together with the bearing
shells. Tighten the screws (2) fixing the connecting rod caps
to a torque of 60 Nm (6 kgm). Using tool 99395216 (3),
further tighten the screws with an angle of 60

°.

540610

CYLINDER HEAD

Before removing the cylinder head, check it is leakproof using
appropriate equipment. Replace the cylinder head if there is
any leakage.

47594

47583

36159

48625

Figure 112

Figure 113

Figure 114

Figure 115

Removing valves

Install and fix tool 99360261 (2) with bracket (4); tighten by
lever (1) until cotters are removed (3); remove the tool (2)
and the upper plate (5), the spring (6) and the lower plate (7).
Repeat the operation on all the valves.
Turn the cylinder head upside down and remove the valves (8).

The planarity (1) is checked using a ruler (2) and a thikness
gauge (3). If deformations exist, surface the head using proper
surface grinder; the maximum amount of material to be
removed is 0.3 mm.

540622

Valves

Removing deposits and checking the valves

Remove carbon deposits using the metal brush supplied.
Check that the valves show no signs of seizure or cracking.
Check the diameter of the valve stem using a micrometer
(see Figure 116) and replace if necessary.

To check the clearance proceed as follows.
Connect the connecting rods to the relative main journals,
place a length of calibrated wire on the latter.

Checking the planarity of the head on the
cylinder block

(Demonstration)

After this process, you need to check the valve
recessing and injector protrusion.

Remove the caps and determine the clearance by comparing
the width of the calibrated wire with the graduated scale on
the case containing the calibrated wire.
Upon final assembly: check the diameter of the thread of the
screws (2), it must be no less than 13.4 mm; if it is, change
the screw. Lubricate the crankpins and connecting rod
bearings. Tighten the screws (2) as described above.

The thread of the screws (2), before assembly, has
to be lubricated with engine oil.

177

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Checking crankpin assembly clearance

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