Iveco Daily Euro 4. Manual — part 28
1. Camshaft on intake side — 2. Hydraulic tightener —
3. Camshaft on exhaust side — 4. MORSE chain —
5. Rocker arms — 6. Hydraulic reacting tappet —
7. Valve assembly.
Description
The timing system is the type with a twin camshaft in the head
and four valves per cylinder with hydraulic tappets.
Motion is transmitted by the crankshaft, via a toothed belt,
to the gear keyed onto the intake valve drive shaft. The drive
transmission of the exhaust valve drive shaft takes place via
a MORSE-type chain kept under tension by a hydraulic
tightener.
The toothed belt, moreover, drives the water pump and the
high-pressure pump CP3 and is kept at the right tension by
an automatic tightener roller.
The four valves move by the action of the “free” rocker arms
(with no supporting shaft).
The rocker arms, one per valve, are always in contact with
the corresponding cam and are kept in this position by a
hydraulic reacting tappet, thereby eliminating the need for
periodical adjustment.
75469
75471
75470
75472
75473
Figure 180
Figure 181
Figure 182
Figure 183
Figure 184
Take out the screws (1) and remove the rear cover (2)
together with its gasket.
Insert a suitable pin (2) in the hole (
⇒) of the chain drive (3).
Take out the screws (4) and (6) with their washers (5) for
fixing gears to the camshafts.
Take out the screws (7) and remove the chain drive (3) from
the overhead (1).
Turn over the overhead (1) and, taking care not to damage
the seats, extract the camshafts (2) and (3) from it.
TIMING SYSTEM DIAGRAM
5412
TIMING SYSTEM
F1A ENGINE
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75474
75475
75476
Figure 185
Figure 186
Figure 187
Using a micrometer (1), measure the diameter of the pins (2)
of the camshaft and, using a bore meter, measure the
diameter of the supporting seats in the overhead.
The difference between these two measurements gives the
existing clearance.
The nominal assembly clearance is 0.037
÷ 0.088 mm.
541210
Camshaft
Checks
The surfaces of the shaft supporting pins and of the cams
must be finely honed; if there is any sign of meshing or
scoring, replace the shaft.
541211
Checking cam lift and pin alignment
Set the shaft (1) on tailstocks and, using a dial gauge on the
middle mounting, check that the alignment error is no greater
than 0.04 mm; replace the shaft if it is. In addition, check the
cam lift: it must be as prescribed; replace the shaft if it is any
different.
MAIN SPECIFICATIONS, FULL-SECTION DISTRIBUTING SHAFT SEATS AND PINS
1. Intake valve camshaft seats — 2. Exhaust valve camshaft seats — 3. Intake valve camshaft — 4. Exhaust valve camshaft.
100
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Figure 188
MAIN SPECIFICATIONS, HOLLOW-SECTION DISTRIBUTING SHAFT SEATS AND PINS
1. Intake valve camshaft seats — 2. Exhaust valve camshaft seats — 3. Exhaust valve camshaft — 4. Intake valve camshaft.
108199
F1A ENGINE
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75471
75478
75477
75479
75469
Figure 189
Figure 190
Figure 191
Figure 192
Figure 193
Lubricate the supporting pins of the shafts (2 and 3) and fit
them in the overhead (1).
Position the overhead (1) and secure it on the mounting
SP.2271 (2).
Position the camshafts (4 and 5) so as to be able to insert the
pins 99360614 (3) into their radial holes through the
threaded holes of the overhead.
Compress the tightener so as to be able to insert a suitable
pin (2) into the hole (
→) of the chain drive (1).
Fit the chain drive (2) on the camshafts and secure it to the
overhead (1) tightening the screws (8) to the prescribed
torque.
Screw down the screws (4) and (7) with the washers (5) and
(6) and tighten them as follows:
- Tighten the screw (7) to a torque of 50 Nm.
- Close further with an angle of 60
°.
- Take out the pin (5).
- Tighten the screw (4) to a torque of 50 Nm.
- Close further with an angle of 60
°.
Fit on the rear cover (2) with a new gasket and tighten the
fixing screws (1) to the prescribed torque.
α
In this operation, take care not to damage the
overhead supporting seats.
NOTE
Use the goniometer 99395216 for the angle
closing.
NOTE
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