Engine Iveco C10/C13/C78/Cursor 13/Cursor 78. Instruction - page 31

The bush surfaces must not show any sign of seizing or
scoring; if they do replace them.

47504

47508

Figure 95

Figure 96

MAIN DATA - CAMSHAFT AND TOLERANCES

The surfaces of shaft supporting pin and cams must be extremely smooth; if you see any sign of seizing or scoring, replace the

shaft and the relative bushes.

MAIN DATA - CAMSHAFT BUSHES AND RELATIVE BLOCK SEATS

* Bush inner diameter after installation

Bushes

Measure the bush inner diameters with a baremeter and replace
them, if the value measured exceeds the tolerance value.
To take down and fit back the bushes, use the proper tool
99360487.

42

SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

TOLERANCES

TOLERANCE CHARACTERISTIC

SYMBOL

ORIENTATION

Perpendicularity

POSITION

Concentricity or coaxial alignment

OSCILLATION

Circular oscillation

IMPORTANCE CLASS ASSIGNED TO PRODUCT CHARACTERISTICS

SYMBOL

CRITICAL

©

IMPORTANT

SECONDARY

Figure 97

71721

A B C

D

E

F

D

L

G

H D

I

A. Drift with seat for bushings to insert/extract. - B. Grub screw for positioning bushings. - C. Reference mark to insert

seventh bushing correctly. - D. Reference mark to insert bushings 1, 2, 3, 4, 5, 6 correctly (red marks). - E. Guide bushing. -
F. Guide line. - G. Guide bushing to secure to the seventh bushing mount. - H. Plate fixing yellow bushing to cylinder head.

- I. Grip. - L. Extension coupling.

Figure 98

71725

The sequence for removing the bushings is 7, 6, 5, 4, 3, 2, 1.
The bushings are extracted from the front of the single seats.
Removal does not require the drift extension for bushings 5,
6 and 7 and it is not necessary to use the guide bushing.
For bushings 1, 2, 3 and 4 it is necessary to use the extension
and the guide bushings.
Position the drift accurately during the phase of removal.

Removal

Figure 99

Assembly

1 Position the bushing to insert on the drift (A) making the

grub screw on it coincide with the seat (B) (Figure 97) on
the bushing.

2 Position the guide bushing (E) and secure the guide

bushing (G) (Figure 97) on the seat of the 7

th

bushing

with the plate (H).

3 While driving in the bushing, make the reference mark (F)

match the mark (M). In this way, when it is driven home,
the lubrication hole on the bushing will coincide with the
oil pipe in its seat.
The bushing is driven home when the 1

st

red reference

mark (D) is flush with the guide bushing (G).

Assemble the drift together with the extension.
To insert bushings 1, 2, 3, 4 and 5, proceed as follows:

71723

Figure 100

To insert the bushing (6), proceed as follows:

- Unscrew the grip (I) and the extension (N).

- Position the extension (N) and the guide bushing (E) as

shown in the figure.

- Repeat steps 1, 2, 3.

Rear

Rear

77795

Replacing camshaft bushes using beater 99360487

SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

43

70000

99374

87051

86290

MAIN DATA TO CONTROL EXHAUST AND

DISCHARGE VALVE SPRING

- fit springs (6) and the upper plate (5);

- apply tool 99360264 (2) and block it with bracket (4);

tighten the lever (1) until cotters are installed (3),
remove tool (2).

VALVE SPRINGS

Fitting the valves and oil seal ring

71724

To insert bushing (7), proceed as follows:

- Unscrew the grip (I) and the extension (N).

- Refit the guide (G) from the inside as shown in the figure.

- Position the bushing on the drift (A) and bring it close

up to the seat, making the bushing hole match the
lubrication hole in the head. Drive it home.
The 7

th

bushing is driven in when the reference mark (C)

is flush with the bushing seat.

Before assembly, the flexibility of the valve springs has to be
checked with the tool 99305047.
Compare the load and elastic deformation data with those
of the new springs given in the following figure.

Rear

Figure 101

Figure 102

Figure 103

Figure 104

Figure 105

Lubricate the valve stem and insert the valves in the
respective valve guides; fit the lower caps (1). Use tool
99360329 to fit the oil seal (2) on the valve guides (3) of the
exhaust valves; then, to fit the valves, proceed as follows.

Free spring height

Valve closed

Valve open

63.

6

49.

5

34.

5

N 454

± 22

N 840

± 42

Should valves not have been overhauled or
replaced, remount them according to numbering
performed on dismounting.

NOTE

44

SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

99281

The camshaft cams directly control rockers: 6 for injectors and 12 for valves.

Rockers slide directly on the cam profiles via rollers.

The other end acts on a bar directly supported by the two valves stems.

A pad is placed between the rocker adjusting screw and the bar.

Two lubrication holes are obtained inside the rockers.

The rocker shaft practically covers the whole cylinder head; remove it to have access to all the underlying components.

Figure 106

44914

44912

99282

Figure 107

Figure 108

Figure 109

PUMP INJECTOR ROCKER

EXHAUST VALVES ROCKER

The bush surfaces must not show any trace of scoring of
excessive wear; otherwise, replace bushes or the whole
rocker.

DISCHARGE VALVE ROCKER

Rocker

SECTION A-A

SECTION B-B

SECTION A-A

SECTION B-B

SECTION A-A

SECTION B-B

Check that the surface of the shaft shows no scoring or signs of seizure; if it does, replace it.

MAIN DATA OF THE ROCKER ARM SHAFT

79171

Shaft

Figure 110

ROCKER SHAFT

SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

45

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