Engine Iveco C10/C13/C78/Cursor 13/Cursor 78. Instruction - page 70

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MAIN DATA OF VALVES AND VALVE GUIDES

* Measurement to be made after driving in the valve guides

60617

Figure 75

Figure 76

Check with a micrometer that the diameter of the valve
stems is as indicated. If necessary, grind the valve seats with
a grinding machine, removing as little material as possible.

MAIN DATA OF VALVE SEATS

1. Intake valve seat — 2. Exhaust valve seat

The valve seats are reground whenever the valves
or valve guides are ground and replaced.

Valve seats

Regrinding — replacing valve seats

NOTE

48625

Valves
Decarbonizing and checking valves

Remove the carbon deposits on the valves with a wire brush.
Check that the valves show no signs of seizure or cracking
and check with a micrometer that the valve stem diameter
comes within the required values (see Figure 76); replace the
valves if it does not.

Figure 77

73537

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SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

Figure 78

41032

Check the valve seats (2). If you find any slight scoring or
burns, regrind them with tool 99305019 (1) according to the
angles shown in figures 78 and 79. If it is necessary to replace
them, using the same tool and taking care not to affect the
cylinder head, remove as much material as possible from the
valve seats so that, with a punch, it is possible to extract them
from the cylinder head.
Heat the cylinder head to 80

÷ 100°C and, using a drift, fit

in the new valve seats (2), chilled beforehand in liquid
nitrogen. Using tool 99305019 (1), regrind the valve seats
according to the angles shown in Figure 79.
After regrinding the valve seats, using tool 99370415 and dial
gauge 99395603, check that the position of the valves in
relation to the plane of the cylinder head is:

- -0.65

÷ -0.95 mm (recessing) intake valves

- -1.8

÷ -2.1 mm (recessing) exhaust valves.

Figure 79

Checking clearance between valve-stem and
associated valve guide

Using a dial gauge with a magnetic base, check the clearance
between the valve stem and the associated guide. If the
clearance is too great, change the valve and, if necessary, the
valve guide.

Valve guides

Replacing valve guides

*

Quote to obtain after valve guides driving.

Figure 80

Replacing injector cases

Removal

60619

To replace the injector case (2), proceed as follows:

- Thread the case (2) with tool 99390804 (1).

The steps described in Figs. 74 - 76 - 77 - 78 need to be
carried out by fixing the tools, with the bracket A, to the
cylinder head.

73538

SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

39

60621

- Using the tool 99390772 (2) remove any residues (1) left

in the groove of the cylinder head.

- Screw the extractor 99342149 (2) into the case (3).

Screw down the nut (1) and take the case out of the
cylinder head.

60620

60622

- Lubricate the seals (3) and fit them on the case (4). Using

tool 99365056 (2) secured to the cylinder head with
bracket A, drive in the new case, screwing down the
screw (1) upsetting the bottom portion of the case.

60623

- Using the reamer 99394041 (1-2), rebore the hole in the

case (3).

Figure 81

Figure 82

Figure 83

Figure 84

Assembly

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SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

60624

47585

Check injector protrusion (2) with the dial gauge (1).
The protrusion must be 1.14 to 1.4 mm.

Checking injector protrusion

71720

INJECTOR CASE ASSEMBLY DIAGRAM

Figure 85

- Using grinder 99394041 (1-2), ream the injector seat in

the case (3), check the injector protrusion from the
cylinder head plane which must be 1.14 to 1.4 mm.

Figure 86

Figure 87

SECTION 4 - OVERHAUL AND TECHNICAL SPECIFICATIONS

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