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COOLING - EXHAUST - TANKChecking
SPECIAL TOOLS
MS 5 54-01 Adapter fo r M.S. 554-07
MS 5 54-06 Adapter fo r M.S. 554-07
MS 5 54-07 Kit for checking the coo ling system sealing
1. CIRCUIT S EALIN G CHECKING
Mount the adapter M.S 554 –01 instead of
the expansion vessel valve.
Connect a t the adapter, the M.S. 554-07
device. Wa rm the engine, then stop it.
P ump, in order to create pressure in the cir-
cuit. Stop pumping at a value lower with 0.1 bar
then the valve calibrating value ( 1.2 bar)
The pressure must not drop, if not, check for
leak and fix it.
Progressively unscrew the device connection
for cooling circuit decompressing , then unscrew
the device, and mount back the expansion vessel
valve.
2. CHECKING ALVE CALIBRATION
M ount t he expansion vessel va lve on
adapter M.S. 554-06 and connect it to the
MS 557-07 device.
P ump to increase the pressure, this must
be stabilized at the valve calibration value 1.2
w ith a checking tolerance of ± 0.1 bar.
The calibra tion value of t he expansion
vessel valve is : 1.2 bar.
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COOLING - EXHAUST - TANKCooling system diagram
ThermostatWa t e rpump
Composition :
1. Engine
2. Cooling radiator
3. Expansion vessel
4. Heating radiator
5. Thermostat support
6. Nozzle Ø 3
7. Purging screw
T. T h ermostat
The operation of the engine fan is controlled by the UCE injection, as follows:
1. For vehicles without air conditioning –cooling engine fan cooling is starting when water temperature is over 99°C;
– cooling engine fan cooling is stopping when water temperature is lower than 96°C.
2. For the vehicles with air conditioning. -cooling engine fan cooling is starting on first step when water temperature is over 99°C;
- cooling e ngine fan c ooling is start ing on second step when water temperature is over
104°C; - cooling engine fa n cooling is switching from second step to first step, when water
temperature is lower than 101°C; -engine fan cooling is stopping when water temperature is lower than 96°C.
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COOLING - EXHAUST - TANK
Radiator
SPECIAL TOOLS
MOT 1202 - 01
Pliers for elastic clips
MOT 453Hoses clamp
DISMOUNTIN G
Drain the air conditioning unit – for the ve-
hicles with air conditioning (see chapter 62” Fill-
ing –Draining the air conditioning circuit”). Disconnect the battery
Dismount the air inlet duct from the battery
screen. Detach from clips the oi l reservoir from the
battery screen, for the ve hicles equipped with
power steering. Clamp the hoses from radiator by means of
MOT 453 device.
Dismount the hoses from radiator by means
of the pliers for elastic clips MOT 1202-01 and
recover the cooling fluid.
Disconnect the engine fan connector (1).
Detach the wiring from clips ( 2) and (3).
Di sconnect the resistance connector ( 4), for
the vehicles with air conditioning. Carefully release the engine fan from the four
attachment clips ( 5) on the radiator- for the
ve hi c l e s e qui ppe d wi t h a i r c ondi t i oni ng,
c onsequently, the four screws ( 6) are
di sm ount e d, f or t he ve hi c l e s without a i r
conditioning.
The vehicles without air conditioning. Carefully remove the engine fan from the
sustaining p oints (7).
Dism oun t t he ra di a t or of f t he si de
attachment supports on the radiator upper
cross beam. Disconnect the two pipes from condenser.
Re l ease t he ra di ator from the lowe r
su p po r tin g buffers togeth er with the
condenser and recover the cooling fluid from
the radiator. Dismount t he condense r a ttachm ent
sc rews on the cooling radiator (for vehicles
with air conditioning).
For vehicles with air conditioning.
REMOU NT I NG
Mount the condenser on the new cooling
radiator (for vehicles with air conditioning).
M ount the radiator-condenser assembly
on the vehicle, by supporting it in the lower
elastic supports and attach it in the supports
of the radiator upper cross beam. Mount the engine fan assembly on the
sustaining supports (7) and attach it in the four
screws (for vehicles without air conditioning).
54
3
1
5
2
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COOLING - EXHAUST - TANKRadiator
* For the vehicles with air conditioning :
- Connect the t wo pipes to the condenser.
- Connect the engine fan resistance connector (1) and the engine fan connector, then attach
it by clips. Connect the battery.
Attach in clips the oil reservoir for power steering and the air inlet pipe on the battery screen.
Perform the cooling circuit filling and purging.
Perform the air conditioning circuit filling with refrigerant fluid HFC 134a (0.600 Kg) and
check for refrigerant fluid leak ( for vehicles with air conditioning).
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Cooling engine fan for vehicles without air conditioning
DISMOUNTIN G
Disconnect the battery (-) terminal.
Remove the air inlet pipe from the attachment of the battery screen.
Detach from clips the oil reservoir of the power steering from the battery screen.
Disconnect the engine fan connector ( 1) and detach from clips wiring of point ( 2)
Dismount the four attachment screws ( 3) of the engine fan on radiator.
Carefully dismount the engine fan assembly from guiding points (4).
REMOUNTING
Check the condition of the fan impeller and of the engine fan electric motor.
Carefully position the engine fan assembly in the guiding points (4).
Mount the attachment screws ( 3) of the assembly on the radiator.
Connect the engine fan connector ( 1).
Attach in clips the wiring in point ( 2).
Attach in clips the power steering oil reservoir on the battery screen.
Mount the air inlet pipe.
Connect t he battery (-) terminal. In case the vehicle is equipped with programmable
r adio-cassettes player, e lectronic clock, etc, there are t o be re-programmed before returning
the vehicle to the client.
Check the engine fan operation: start the vehicle engine and disconnect the water
temperature sensor. The engine fan must start. Reconnect the water temperature sensor
then by means of the CLIP tester erase the memorized failure corresponding to the water
temperature sensor.
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COOLING - EXHAUST - TANK
COOLING ENGINE FAN NOT WORKING
(for vehicles without air conditioning)
Replace fuse
F01
.
Check fuse F01 from engine compartment. Is it good?
Replace water temperature sensor.
Replace the control relay of the cooling engine fan.
Replace the cooling engine fan assembly . Start the vehicle’s
engine.
Disconnect the water
temperature sensor. Is the
cooling engine fan working?
Check the control relay of the cooling engine fan Is it good?
Is any voltage between pins 1
and 2 of the cooling engine fan connector?
The wirin g
is
damaged. Fix it. Stop the vehicle engine.
Check the continuity and resistance
against vehicle mass between:
- pin B2 connector of water temperature sensor pin 13 UCE i njection;
- pin B1 connector of water temperature sensor pin 73 UCE i njection;
- pin 3 connector of cooling engine fan control relay exit fuse F01;
- pin 5 connector of cooling engine fan control relay pin 2 connector of
cooling engine fan
- pin 1 connector of cooling engine fan vehicle mass;
- pin 1 connector of cooling engine fan control relay pin D 5 connector
of actuators relay;
- pin 2 connector of cooling engine fan control relay pin 8 UCE injection.
Ar e they good?
Replace UCE injection.
AT T E N T I O N !
The injection computer damaging i s probably due to an e lectric
shock. Before mounting a new injection computer, the cause of its
damaging must be found.No Ye s
Yes
No No
Ye s Ye s
No
Ye s
Diagnostic – failures interpretation
at vehicles without air conditioning
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COOLING - EXHAUST - TANK
Cooling engine fan for vehicles with air conditioning
DISMOUNTIN G
Disconnect the battery (-) terminal.
Remove the air inlet pipe from the attachment of the battery screen.
Detach from clip the power steering oil reservoir from the battery screen.
Disconnect the engine fan connector ( 1)
Detach wiring from clips ( 2) and (3).
Disconnect the connector of the cooling engine fan resistance (4).
Carefully dismount the engine fan assembly from the radiator, from sustaining points (5).
REMOUNTING
Check the condition of the fan impeller and of the engine fan electric motor.
Carefully mount the engine fan assembly in the sustaining points (5).
Connect the connector of the engine fan resistance ( 4).
Connect the cooling engine fan connector ( 1) and attach it in clip (3) then in clip (2).
Attach in clips the power steering oil reservoir on the battery screen. Mount the air inlet
pipe.
Connect the battery (-) terminal. In case the vehicle is equipped with programmable
r adio-cassettes player, electronic clock, etc, there are t o be re-programmed before returning
the vehicle to the client. Check the engine fan operation: start the vehicle engine and disconnect the water
temperature sensor. The engine fan must start. Reconnect the water temperature sensor
then by means of the CLIP tester erase the memorized failure corresponding to the water
temperature sensor.
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COOLING - EXHAUST - TANKWa ter pump
DISMOUNTIN G
Place t he vehicle on a two columns elevator
Disconnect the battery
Drain the cooling circuit using the lower hose from the water pump.
Dismount :
- distribution belt ( see chapter 11 “Distribution belt”);
- tightening cam ( 1);
- water pump attachment screws and nut.
Remove the water pump through the upper part of the engine compartment.
TIGHTENING MOMENTS (daNm)
Tightening cam nut5
Crankshaft pulley hub screw2+680± 60
Right pendular support screws6.2
Hydro-elastic buffer nut3.7
W ater pump screws2.2
Water pump nut1
Wheels screws7.5
SPECIAL TOOLS
MOT. 1202-01 Pliers for elastic clips
MOT. 1505 Device for belts tension me asurement
MOT. 1135-01 Device for distribution belt tensioning
MOT. 545 Engine sustaining device
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