Iveco Daily Euro 4. Manual — part 23
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.
75296
Figure 98
Figure 99
75297
Figure 100
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.
Undersize classes are of:
0.254 - 0.508 mm.
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.
NOTE
It is advisable to enter the measurements in a table.
See Figure 99.
NOTE
NOTE
NOMINAL
VALUE
NOMINAL
VALUE
MINIMUM
∅
MAXIMUM
∅
NOMINAL
VALUE
MINIMUM
∅
MAXIMUM
∅
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75299
45066
Figure 101
Figure 102
MAIN CRANKSHAFT TOLERANCES
SYMMETRY BETWEEN MAIN JOURNALS AND CRANK-
PINS
1. Crank pins
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.
94
±
0,125
180
°±
15’
The checks on the tolerances indicated in the
figures must be made after grinding the crankshaft
pins.
NOTE
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TOLERANCE CHARACTERISTIC
SYMBOL
SHAPE
Circularity
○
SHAPE
Cylindricality
DIRECTION
Parallelism
DIRECTION
Perpendicularity
⊥
OF POSITION
Concentricity or coaxiality
OSCILLATION
Circular oscillation
↗
OSCILLATION
Total oscillation
↗↗
CLASS OF IMPORTANCE ASCRIBED TO THE PRODUCT CHARACTERISTICS
SYMBOL
CRITICAL
E
IMPORTANT
⊕
SECONDARY
⊝
75303
Figure 103
Figure 104
Figure 105
Figure 106
Figure 107
INTERMEDIATE JOURNALS No. 2-4
INTERMEDIATE JOURNAL No. 3
CRANKPINS
* On both races, on all 360
°.
- Rolling turns: 3 approach, 12 effective, 3 out.
- Rolling speed: 56 rpm.
- Decrease in crankpin race depth after rolling: 0.15 — 0.30
mm*.
- Decrease in main journal race depth 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
108189
108190
108192
108191
honed
waviness
waviness
RACE AREA FOR ALL MAIN JOURNALS
(MACHINED BY TURNING)
honed
CRANKPIN GROOVE AREA
(EXTERNAL MILLING PROCESSED)
honed
in circumferential direction
in axial direction
honed
in circumferential direction
waviness
in axial direction
waviness
honed
B
e
fo
re
ro
llin
g
B
e
fo
re
ro
llin
g
B
e
fo
re
ro
llin
g
B
e
fo
re
ro
llin
g
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75305
75306
75307
90063
Figure 108
Figure 109
Figure 110
Figure 111
Take out the screws (4) and replace the phonic wheel (3).
The screws (4) hey must be tightened to a torque of 15 Nm.
Replacing timing control gear
On finding the timing control gear teeth (1) damaged or
worn, remove them from the crankshaft (2) using a suitable
extractor.
The new gear is fitted onto the crankshaft by heating it to a
temperature of 200
°C for no longer than 15 minutes.
On completing assembly and after the gear has cooled, it
must withstand a torque of 150 Nm without slipping.
ENGINE ASSEMBLY
The following parts must be replaced with new ones at the
time of assembly: retaining rings, seals and gaskets, screws
whose thread is coated with sealant.
Fit on the oil spray nozzles (2) and tighten the couplings (1)
to the prescribed torque.
The main bearings (1) are supplied as spare parts undersized
on the inside diameter by 0.254
÷ 0.508 mm.
540811
Measuring main journal assembly
clearance
Mount the crankshaft (1).
Check the clearance between the crankshaft main journals
and their respective bearings by proceeding as follows:
- Thoroughly clean the pins.
- Apply a calibrated wire onto the main journals.
Assembling main bearings
Thoroughly clean the top main bearing shells (1) and position
them in the crankcase.
Not having found it necessary to replace the main
bearings, they need to be fitted back on in the same
sequence and position found upon disassembly.
NOTE
Do not do any accommodating on the bearings.
NOTE
The middle half ring (2) is fitted with thrust washers.
NOTE
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