Iveco Stralis AT/AD. Manual — part 258
60256
Figure 58
Predominance control
It is equipped with a predominance adjustment device.
KNORR - BREMSE AC 597 B
60255
bar
The operations to carry out to adjust the predominance of
the servo control valve type KNORR — BREMSE AC 597 B
are performed in the following order:
- undo the screw (2) from the silencer body;
- insert an Allen wrench into the hole through the silencer
body and turn the hexagonal hole of the body (1);
- turning it CLOCKWISE increases the predominance;
- turning it ANTICLOCKWISE decreases the predo-
minance.
Figure 59
bar
The operations to carry out to adjust the predominance of
the servo control valve type WABCO 973 009013 are
performed in the following order:
- Remove the screws (2) and take off the cover (3).
- Turn the screw (1) to adjust the predominance.
- Turning it CLOCKWISE decreases the predominance.
- Turning it ANTICLOCKWISE increases the predo-
minance.
WABCO 9730090130
3
2
2
1
11
41
42
22
12
43
S
TRALIS
AT/AD
90
AIR SYSTEM - BRAKES
Base - January 2003
TROUBLE
POSSIBLE CAUSE
REMEDY
Air leaks from the outlet
when at rest
Leaks from the gaskets.
Overhaul the device, replacing the worn parts.
Exhaust valve and seat defective
Overhaul the device, replacing the worn parts.
Outlet pressures not as
required
Air leaks from the gaskets.
Overhaul the device, replacing the worn parts.
Pistons and seats worn or defective.
Overhaul the device, replacing the worn parts.
Springs yielded.
Overhaul the device, replacing the worn parts.
73920
71953
Figure 60
Figure 61
Figure 62
Trailer servo control valve (vehicles with EBS)
This valve has the job of ensuring all braking levels (service,
parking, emergency) and adjusting trailer predominance.
This device provides emergency and parking braking for the
tractor and trailer.
Additionally, it makes it possible to check the braking effect
of the tractor. This is vital when the vehicle is parked on a
steep slope.
79514
Pressure test point valve
794310
Parking brake hand control valve
(vehicles suited to towing)
The pressure test points are in the pipes or tanks of the
pneumatic system in order to make it easier to hook up
pressure gauges for fault diagnosis.
AIR SYSTEM - BRAKES
91
S
TRALIS
AT/AD
Fault Diagnosis (parking brake control valve)
TROUBLE
POSSIBLE CAUSE
REMEDY
Air leaks from the outlet
with the control lever:
in the release position
Exhaust valve, seat or seal defective
Check and overhaul the device, replacing any defective
parts
in the braking position
Control valve, seals and valve to control
component worn
Thoroughly clean the various parts comprising it
Difficulty in turning the
control lever
Interference in the control valve
Overhaul the device and moisten all the sliding parts
Manual control valve to slow down the trailer
(optional extra)
79515
73922
Figure 63
Figure 64
This component, in the parking circuit between the manual
control valve and the trailer servo control valve, makes it
possible to activate braking to slow down just the semitrailer
according to the control given by the driver. It is an optional
fitting and is anyhow bound by the current type-approval
regulations in the various countries.
793336
Parking brake control manual dis-
tributor (standby vehicles)
The apparatus, inserted into tractor parking brake circuit,
allows to actuate vehicle help and parking braking by releasing
the air in spring cylinders.
S
TRALIS
AT/AD
92
AIR SYSTEM - BRAKES
Base - January 2003
TROUBLE
POSSIBLE CAUSE
REMEDY
Air leaks from the outlet
with the control valve lever
in the brake release position
Piston, outlet valve, seals worn or defective.
Clean thoroughly, check the rubber parts and the seats are
sound.
Air leaks from the outlet
with the control valve lever
in the emergency or parking
braking position
Piston and associated seal defective or deterio-
rated.
Clean thoroughly, check the parts and overhaul the device,
replacing the defective parts.
Air leaks from the cover
of the control valve lever
Plate, gasket, seals worn.
Clean the parts thoroughly, check the surfaces of the
gasket and seals, check the integrity of the rubber parts and
the relevant seats. Overhaul the device, replacing the de-
fective or worn parts, and restore the mating faces if
necessary.
Control valve lever hard
to turn
Interference inside the control valve.
Clean thoroughly and check all the component parts.
Overhaul the device, replacing defective parts. During as-
sembly, grease all the sliding parts in moderation.
If you find any defects or wear such as to jeopardize oper-
ation, replace the complete device.
Figure 65
73923
Controlled pressure valve
This permits compressed air to pass in the direction shown
by the arrow on the valve body, preventing its backflow.
33987
2
1
Its job is to break off the flow of air to the ASR solenoid valve
when the pressure of the rear axle system falls under 7.5 bars
after a breakdown or too much air being drawn off.
793319
Check valve
(vehicles suited to towing)
Figure 66
Low-pressure switch
Figure 67
The purpose of this component is to warn the driver, with
indicator lights on the CLUSTER, and the electronic control
unit of low pressure in the system.
73924
AIR SYSTEM - BRAKES
93
S
TRALIS
AT/AD
Fault Diagnosis
TROUBLE
POSSIBLE CAUSE
REMEDY
Vent at outlet
Diaphragm leaks
Overhaul the device, replacing any worn parts
Air leaks from the join be-
tween the two half-bodies
Leakage from the diaphragm fitting
Vent on delivery
(into the atmosphere)
with supply at a lower
pressure than the setting
Leakage from inlet valve or its seat
Overhaul the device, replacing any worn parts
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст