Engines Iveco C10,C13, Cursor 10, Cursor 13. Manual

MEASURING CRANKPINS

When grinding, pay the utmost attention to the values of the
unions of the main journals and of the crankpins given in
Figure 19 and Figure 20.

47535

47536

Figure 21

Figure 22

MEASURING THE MAIN JOURNALS

Measuring the main journals and crankpins

Before grinding the journals, use a micrometric gauge (1) to
measure the journals of the shaft (2) and establish, on the
basis of the undersizing of the spare bearing shells, to what
diameter it is necessary to reduce the journals.

It is advisable to note the measurements in a table
(Figure 22).

All the main journals and crankpins should always
be ground to the same undersizing class so as not
to alter the balance of the shaft.

Figure 23

Table for noting down the measurements of the main journals and crankpins of the crankshaft.

MAIN JOURNALS

36061

∅ MIN.

∅ MAX.

∅ MIN.

∅ MAX.

CRANKPINS

NOTE

SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

F3B CURSOR ENGINES

Base - May 2007

Preliminary measurement of main and big end bearing shell selection data

For each of the journals of the crankshaft, it is necessary to carry out the following operations:
MAIN JOURNALS:
- Determine the class of diameter of the seat in the

crankcase.

- Determine the class of diameter of the main journal.

- Select the class of the bearing shells to mount.

CRANKPINS:
- Determine the class of diameter of the seat in the

connecting rod.

- Determine the class of diameter of the crankpin.

- Select the class of the bearing shells to mount.

DEFINING THE CLASS OF DIAMETER OF THE SEATS FOR BEARING SHELLS ON THE CRANKCASE

On the front of the crankcase, two sets of numbers are marked in the position shown (Figure 24 at top).

- The first set of digits (four) is the coupling number of the crankcase with its base.

- The following seven digits, taken singly, are the class of diameter of each of the seats referred to (Figure 24 at bottom).

- Each of these digits may be 1, 2 or 3.

47535

106.300 to 106.309

106.310 to 106.319

106.320 to 106.330

Figure 24

CLASS

MAIN BEARING HOUSING

NOMINAL DIAMETER

SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

F3B CURSOR ENGINES

To obtain the required assembly clearances, the main bearing and big end bearing shells have to be selected as
described hereunder.

This operation makes it possible to identify the most suited bearing shells for each of the journals of the shaft (the bearing shells
may even have different classes for different pins).

red

red/black

green

green/black

STD

1.965 to 1.975

1.976 to 1.985

+0.127

2.028 to 2.038

2.039 to 2.048

+0.254

2.092 to 2.102

2.103 to 2.112

+0.508

2.219 to 2.229

2.230 to 2.239

Depending on the thickness, the bearing shells are selected
in classes of tolerance marked by a colour (red-green -
red/black - green/black).

Figure 25 gives the specifications of the main bearing and big
end bearing shells available as spare parts in the standard sizes
(STD) and in the permissible oversizes (+0.127, +0.254,
+0.508).

Figure 25

red

red/black

green

green/black

STD

3.110 to 3.120

3.121 to 3.130

+0.127

3.173 to 3.183

3.184 to 3.193

+0.254

3.237 to 3.247

+0.508

3.364 to 3.374

Big end bearing shells

Main bearing shells

Selecting the main bearing and big end bearing shells

NOTE

SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

F3B CURSOR ENGINES

Base - May 2007

DEFINING THE CLASS OF DIAMETER OF THE MAIN JOURNALS AND CRANKPINS (Journals with nominal diameter)
Main journals and crankpins: determining the class of diameter of the journals.
Three sets of numbers are marked on the crankshaft in the position shown by the arrow (Figure 26 at top):
- The first number, of five digits, is the part number of the shaft.
- Under this number, on the left, a set of six digits refers to the crankpins and is preceded by a single digit showing the status

of the journals (1 = STD, 2 = -0.127), the other six digits, taken singly, give the class of diameter of each of the crankpins
they refer to (Figure 26 at top).

- The set of seven digits, on the right, refers to the main journals and is preceded by a single digit: the single digit shows the

status of the journals (1 = STD, 2 = -0.127), the other seven digits, taken singly, give the class of diameter of each of the
main journals they refer to (Figure 26 at bottom).

Figure 26

89.970 to 89.979

89.980 to 89.989

89.990 to 90.000

CLASS

CRANKPIN

NOMINAL DIAMETER

99.970 to 99.979

99.980 to 99.989

99.990 to 100.000

CLASS

MAIN JOURNALS

NOMINAL DIAMETER

SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

F3B CURSOR ENGINES

Content .. 61 62 63 64 ..

Engines Iveco C10,C13, Cursor 10, Cursor 13. Manual - part 63