Iveco Daily. Manual

88622

Figure 251

Figure 252

88623

88624

Cover the air, exhaust gas and lubricating oil inlets and
outlets. Thoroughly clean the outside of the turbocharger
using anticorrosive and antioxidant fluid. Disconnect the pipe
(2) from the union of the pressure relief valve (1) and fit on
it the pipe of the device 99367121 (3, Figure 252).

542418

Pressure relief valve

Checking and adjusting pressure relief valve

Rest the tip of the dial gauge (1) with a magnetic base on the
end of the tie rod (2) and zero it. Using the device 99367121
(3), introduce compressed air into the valve casing (4) at the
prescribed pressure and make sure this value stays constant
throughout the check; replace the valve if it doesn’t. In the
above conditions, the tie rod must have made the prescribed
travel.

Changing the pressure relief valve

Remove the fastener (2) of the tie rod on the lever (1) and
take off the valve (5) from the turbocharger by pulling out the
fastening screws (6).

Fit the new valve by carrying out the operations for removal
in reverse order and adjust the travel of the tie rod as
described under the relevant heading.

If a different value is detected, slacken the nut (3) and rotate
the tie rod (4) as required.

Figure 253

On finding irregular engine operation due to the
turbocharging system, it is first expedient to
perform the checks on the turbocharger, check the
efficiency of the seals and the fixing of the couplings,
additionally checking there is no clogging in the
intake sleeves, air filter or radiators. If the
turbocharger damage is due to a lack of lubrication,
check that the oil circulation pipes are not burst or
clogged, in which case replace them or eliminate
the trouble.

NOTE

Before fitting the turbocharger on the engine, it is
necessary to fill the central body with engine
lubricating oil.

NOTE

584

F1C ENGINE

AILY

Base - May 2004

62870

Figure 254

542410

GARRET GT 2256 T variable
geometry turbosupercharger
(engine F1C E0481 B - 166 HP)

General

The variable geometry turbosupercharger consists of the
following:
- centrifugal supercharger (1);
- turbine (2);
- set of mobile blades (3);
- mobile blade control pneumatic actuator (4), vacuum

controlled by proportional solenoid valve controlled by
EDC 16 ECU.

Variable geometry enables:
- to increase the speed of the exhaust gases running into

the turbine at low engine rpm;

- to decrease the speed of the exhaust gases running into

the turbine at high engine rpm.

To obtain the max. engine volumetric efficiency also at low
rpm (with on-load engine).

Operation at low engine rpm

1. TURBINE - 2. MOBILE BLADES - 3. PNEUMATIC ACTUATOR - 4. REVOLVING RING

Operation at high engine rpm

82871

Figure 255

62872

Figure 256

When engine is running at low speed, the exhaust gases
show weak kinetic energy; under these conditions a
traditional turbine shall rotate slowly, thus providing a limited
booster pressure.
In the variable geometry turbine (1), the mobile blades (2) are
set to max. closed position and the small through-sections
between the blades increase the inlet gas speed. Higher inlet
speeds involve higher tip speeds of the turbine and therefore
of the turbosupercharger.
Engine speed increase results in a gradual increase of exhaust
gas kinetic energy, and also in turbine (1) speed and booster
pressure increase.

The ECU, through the actuator control solenoid valve,
modulates the vacuum acting on the diaphragm, so actuator
(3) controls through the tie rod, the gradual opening of the
mobile blades (2) until reaching the max. open position.
Blade through-sections results larger thus producing a speed
decrease in exhaust gas flow through the turbine (1) with
speeds equal to or lower than those of the low rpm
condition.
Turbine (1) speed is therefore adjusted to a proper value
enabling suitable engine operation at high speeds.

F1C ENGINE

585

AILY

Base - May 2004

Proportional

solenoid

valve

controlling

turbocharger actuator

62876

Figure 257

The solenoid valve modulates the low pressure controlling
the turbocharger actuator, taken from the air circuit of the
servo brake, according to the information exchanged
between the electronic control unit and the sensors: engine
speed, throttle pedal position and pressure/temperature
fitted on the intake manifold.

As a result, the actuator varies the opening of the blades of
the turbocharger that adjust the flow of exhaust gases.

62869

TURBOCHARGING FUNCTIONAL DIAGRAM

1. Variable geometry turbocharger - 2. Pneumatic actuator - 3. Proportional solenoid valve - 4. Air filter -

5. EDC 16 control unit - 6. Servo brake - 7. Vacuum device - 8. High-pressure pump.

Figure 258

The actuator diaphragm, connected to the control rod, is
governed by the low pressure on the top of the actuator.

The low pressure modulated by the proportional solenoid
valve varies the movement of the diaphragm and, as a result,
of the rod governing the turbine’s mobile blades.

62875

SECTION ON THE ACTUATOR

Figure 259

Actuator

586

F1C ENGINE

AILY

Base - May 2004

62873

Figure 260

REPAIRS

542451

Checking and adjusting the actuator

Cover air, exhaust gas and lubricant inlets and outlets.

Clean the turbosupercharger outside accurately using
anticorrosive and antioxidant fluid and check the actuator
(6).

Clamp the turbosupercharger in a vice.

Apply vacuometer 99367121 (1) pipe to actuator (6) hose.

Apply the magnetic base gauge (2) to exhaust gas inlet flange
in the turbine.

Set gauge (2) feeler pin on tie rod (3) end and set gauge (2)
to zero.

Operate the vacuum pump and check whether the tie rod
(3) stroke values correspond to the vacuum values shown in
the following table:

If a different value is found, loosen nut (5) and operate on the
knurled ring nut (4) as required.

Once the adjustment has been carried out, tighten the nut
(5) to torque 5.6

÷ 6.8 Nm.

During the check the vacuum value shall not fall,
otherwise the actuator shall be replaced.

NOTE

NOT ALLOWED ARE:

- any replacement or regulation of the

actuator, since the calibration of such
component is made in an optimal way
for

each

turbocharger

and

guaranteed for the turbocharger;

- any operation on nut (5) and ring nut

(4), since such operation does not
change engine supply characteristics
but may impair engine reliability and
duration.

Ring nut (4) is sealed with antitempering
yellow paint.

In case of engines under guarantee, each
above

specified

intervention

and/or

alteration to paint applied on ring nut (4)
causes the lapse of the guarantee.

NOTE

F1C ENGINE

587

AILY

Base - May 2004

vacuum 0 mm Hg

Fully open valve

vacuum 180 mm Hg

Valve stroke

2.5 mm

vacuum 450 mm Hg

Valve stroke

10.5 mm

Content .. 170 171 172 173 ..

Iveco Daily. Manual - part 172