Iveco Daily Euro 4. Manual — part 60
The measurements must be made for each single cylinder at
three different heights up the liner and on two planes at right
angles to each other: one parallel to the longitudinal axis of
the engine (B) and the perpendicular (A); the greatest wear
is generally found on this last plane with the first
measurement.
On finding ovalization, taper or wear, go ahead and
bore/grind and finish the face of the cylinder liners. The
refacing of the cylinder liners should be done in relation to
the diameter of the pistons supplied as spare parts oversized
by 0.4 mm of the nominal value and to the prescribed
assembly clearance.
18837
87781
Figure 118
Figure 119
Once the engine removal is complete, carefully clean the
cylinder block. For the cylinder block transportation use the
suitable rings.
Carefully check that the crankcase has no cracks in it.
Check the state of the plugs. If they are rusty or there is any
doubt about their seal, replace them. When fitting the caps
into place, apply Loctite 270 sealant (IVECO NO. 93162429)
to the same. Examine the surfaces of the cylinder liners; they
must show no sign of meshing, scoring, ovalization, taper or
excessive wear. The inside diameter of the cylinder liners is
checked, to ascertain the extent of ovalization, taper and
wear, using the bore meter 99395687 (1) fitted with a dial
gauge previously reset on the ring gauge of the diameter of
the cylinder liner or on a micrometer.
CYLINDER BLOCK
Checks and measurements
Figure 120
* Surface roughness parameters:
R1 =
4
÷ 10 μm
Rz
=
3
÷ 8 μm
Ra
=
0,3
÷ 0,6 μm
W1 <
2
μm
Permissible surface porosity for machined cylinder
(see Figure 121)
ZONE B1 = Area of greatest mechanical stress,
segment/liner
contact:
No.2
non-continuous
porosities
are
permissible max. 0.5x0.5.
ZONE B2 = Surface involved in segment rubbing:
No.2 non-contiguous porosities are
permissible max. 1x0.8.
C
C
100%
100%
87782
Figure 121
87783
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For undersized crankpins, letter M.
For undersized main journals, letter B.
For undersized crankpins and main journals, letter MB.
See that the head mating surface, on the cylinder block, has
no deformation.
This check can be made, after taking out the grub screws (3),
with a surface plate spread with carbon black or with a
calibrated rule (1) and a feeler gauge (2). After ascertaining
the areas of deformation, level the bearing surface with a
grinding machine.
88290
Figure 122
Figure 123
87784
Figure 124
The main journals and crankpins must always be
ground to the same undersize class.
The undersizing performed, on the main journals or
crankpins, must be marked by punching on the side
of crank arm no. 1.
TABLE IN WHICH TO ENTER THE MEASUREMENTS OF THE CRANKSHAFT MAIN JOURNALS AND CRANKPINS
5408
CRANKSHAFT
540810
Measuring main journals and crank
pins
Checking head mating surface on cylinder
block
On finding signs of seizure, scoring or excessive ovalization
on main journals and crankpins, it is necessary to regrind the
pins. Before grinding the pins (2), measure the shaft pins with
a micrometer (1) to establish to what diameter it is necessary
to decrease the pins.
75298
The crankcase can only be surfaced after making
sure that, on completing the work, the piston
protrudes from the cylinder liner by no more than
the prescribed value.
It is advisable to enter the measurements in a table.
See Figure 123.
NOTE
NOTE
NOTE
NOMINAL
VALUE
NOMINAL
VALUE
NOMINAL
VALUE
∅ MIN
∅ MAX
∅ MIN
∅ MAX
The undersize classes are:
0.254 — 0.508 mm.
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87785
87786
Figure 125
Figure 126
MAIN CRANKSHAFT TOLERANCES
SYMMETRY
BETWEEN
MAIN
JOURNALS
AND
CRANKPINS
1.
Crankpins
2.
Main journals
3.
Normal position
Checking crankshaft
After grinding, keep to the following:
- Round off the edges of deburring the holes for
lubrication of the main journals and crankpins.
The checks on the tolerances indicated in the
figures must be made after grinding the crankshaft
pins.
NOTE
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TOLERANCE CHARACTERISTIC
GRAPHIC SYMBOL
SHAPE
Circularity
○
SHAPE
Cylindricality
ORIENTATION
Parallelism
ORIENTATION
Perpendicularity
⊥
POSITION
Concentricity or coaxiality
OSCILLATION
Circular oscillation
↗
OSCILLATION
Total oscillation
↗↗
CLASS OF IMPORTANCE ATTRIBUTED TO PRODUCT CHARACTERISTICS
GRAPHIC SYMBOL
CRITICAL
E
IMPORTANT
⊕
SECONDARY
⊝
87787
87789
87788
87790
87791
Figure 127
Figure 128
Figure 129
Figure 130
Figure 131
INTERMEDIATE JOURNALS NO. 2-4
INTERMEDIATE JOURNAL NO. 3
CRANKPINS
*
As far as both values are concerned, for the whole 360
°.
- Rolling turns: 3 approach, 12 effective, 3 out.
- Rolling speed: 56 rpm.
- Reduction of the connecting rod pin slot diameter after
rolling: 0.15
÷ 0.30 mm*.
- Reduction of the journal slots after rolling: 0.15
÷ 0.30
mm.
* Measured with calibrated rollers
∅ 2.5 mm.
JOURNAL ON TIMING SYSTEM SIDE
JOURNAL ON FLYWHEEL SIDE
MAIN DATA OF MAIN JOURNALS AND CRANKPINS
Since, during the 0.254 and 0.508 mm undersizing
on the diameter of the crankpins and main journals,
the rolled portion of the side races of the pins may
get involved, it is necessary to turn the races
keeping to the data given in the figure and to do the
rolling keeping to the following instructions.
Rolling force:
- 1
st
main journal 925
±25 daN.
- 2
nd
— 3
rd
— 4
th
— 5
th
main journal 1850
±50 daN.
- crankpin 1850
±50 daN.
NOTE
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