Ad BLUE

Technical training - ASTRA

HD8 Euro 5 Series

TECHNICAL DOCUMENTATION FOR TRAINING PURPOSES ONLY. NO REGULAR UPDATES PROVIDED



Engines CURSOR Euro 5



Electrical/Electronic System

Technical training - ASTRA

HD8 Euro 5 Series 

Engines CURSOR Euro 5



Electrical/Electronic System

The company ASTRA VEICOLI INDUSTRIALI reserves the right to make any modifications to vehicles for technical or commercial reasons at any time ; the information, description and illustrations contained in this publication are therefore correct at the time of going to press.

ASTRA Veicoli Industriali Product Support Via Caorsana, 79 - 29100 PIACENZA (Italy) Tel. 0523/5431 - Fax 0523/543459 Publicatio Publication n nr. A3501075 A3501075 Prima edizione: September 2006 Prepared by SIPAL S.p.A. - TORINO (Italy)

NOx EMISSIONS CONTROL SYSTEM

ASTRA – Technical Training


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HD8 EURO 5



PAGE LEFT INTENTIONALLY BLANK

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CONTENTS Page NOx emissions emissions control control system system (SCR)...................... (SCR)................................ ..................... ...................... ...................... ..................... .......... 5 Overview................. Overview............................ ...................... ...................... ....................... ....................... ...................... ...................... ...................... ...................... ............. .. 5 Functiona Functionall princple............. princple........................ ....................... ....................... ...................... ...................... ....................... ....................... ...................... ............. 5 Function Function ...................... ................................. ....................... ....................... ...................... ...................... ....................... ....................... ...................... .................. ......... 6 AD BLUE ........................ ........... .......................... .......................... ......................... ......................... .......................... .......................... .......................... ................. .... 7 Urea.......... Urea ..................... ....................... ....................... ...................... ....................... ....................... ...................... ....................... ....................... ...................... .............. ... 7 Characteri Characteristics stics of the AdBlue AdBlue solution solution ...................... ................................. ...................... ...................... ...................... ................... ........ 8 Particular Particular features features of AdBlue ...................... ................................. ...................... ...................... ...................... ...................... ...................... ........... 8 Safety sheet........................ sheet................................... ...................... ....................... ....................... ...................... ...................... ...................... ...................... ............. 9 AD BLUE storage .......................... ............. .......................... ......................... ......................... .......................... .......................... .......................... ............... .. 10 AD BLUE storability ......................... ............ .......................... .......................... ......................... ......................... .......................... .......................... ............. 11

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NOx EMISSIONS CONTROL SYSTEM (SCR) Overview To limit the emissions of nitrogen oxides (NOx) in exhaust gases to within the limits required by Euro 5, with low fuel consumption, the vehicle has been fitted with a system for post-treating these substances in exhaust gases, based on SCR technology (Selective Catalytic Reduction).. SCR technlogy foresees use of an additive – known as AdBlue – AdBlue – added to the exhaust gases that are then conveyed to a catalytic converter, which transforms nitrous oxides into inert compounds: free nitrogen (N2 and water vapour (H2O)

Functional principle The pump module draws up the reagent solution (AdBlue) from the reservoir and delivers it under pressure to the dosing unit for injection into the exhaust pipe upstream of the catalytic converter. The first phase of the process takes place in the pipe upstream of the converter: by effect of the exhaust gas temperature, the reagent solution vaporises, and by hydrolysis converts into ammonia (NH3) and carbon dioxide (CO2). At the same time, the evaporation of the solution causes a drop in exhaust gas temperature, bringing it down to the temperature required by the conversion process. The exhaust gas at the correct temperature for the reaction and with added ammonia is delivered to the converter where the second phase of the process takes place: reacting with the oxygen in the exhaust gas, the ammonia converts into free nitrogen (N2) and water vapour (CO2).

NITROGEN + WATER VAP.

High ex. gas temp TITANIUM, VANADIUM Ammonia + CO2

AMMONIA

5

HD8 EURO 5



Function The pump module draws up the reagent solution (AdBlue) from the reservoir and delivers it under pressure to the dosing module for injection into the exhaust pipe upstream of the catalytic converter. The SCR system is electronically controlled by the DCU (Dosing Control Unit), which regulates the flow-rate of the AdBlue solution injected into the system according to: -

Engine speed,

-

Torque level

-

Exhaust gas temperature

-

Nitrogen oxide content

-

Intake air humidity

AdBlue may only be injected injected into the SCR system in certain conditions: conditions: Engine temperature must be greater than 40°C Catalytic converter temperature must be greater than 180°C Engine speed must be greater than 400 rpm Engine torque demand must be greater than 5% In addition, the engine control unit must be showing no current errors related to: -

Injectors

-

Turbo pressure

-

Injection pressure

-

Engine revs sensors

-

Humidity sensors

-

Air temperature sensors

There must be now current errors in the DCU related to its control systems (AdBlue pressure sensors, doser, etc.).

HD8 EURO 5

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AD BLUE AdBlue is the European level brand name of a high quality water-based urea solution, made up of urea and demineralised water , necessary for SCR function. f unction.

Urea Chemical formula of urea:

N2 H4

Discovered in urine in 1773, this was the first organic compound to be synthetically reproduced using lead cynate and a water based ammonia solution. Urea is used in the production of fertilisers for agriculture, as well as in the foodstuffs, pharmaceutical and cosmetics industries. Urea is present in the blood and in urine, since it is the final product of the metabolic breakdown of proteins. The excretion function is carried out by the kidneys, through urine, in varying quantities.

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HD8 EURO 5



Characteristics of the AdBlue solution It is classified as a non-hazardous substance (EU Directive 67/548/EC) both for human health and the environment. It has the following characteristics: Transparent, odourless liquid Non-inflammable Non-esplosive Non-corrosive May cause irritation Crystallisation temperature = – 11 °C Sold by the litre Specification DIN V 70070 Specific composition of Std. DIN V 70700: 32.5% urea 67.5% water. The concentration of 32.5% was chosen because this gives a freezing point of –11°C.

Particular features of AdBlue The remainder, when all the water has evaporated, consists of white crystals of urea. These crystals are completely innocuous. If burned, they may release toxic fumes containing ammonia, carbon dioxide and nitrogen oxides. The materials compatible compatible and widely used with AdBlue AdBlue are: Carbon steel Stainless steel Aluminium Polyethylene (PE) Polyvinylchloride (PVC) Polypropylene (PP) Ethenpropendimonomer (EPDM) for gaskets Do not use with copper, zinc and related alloys

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SAFETY SHEET Contact with eyes Repeated or prolonged contact may cause irritation. 

Contact with the skin Repeated or prolonged contact may cause irritation. Wash abundantly with water Rinse with water for 15 minutes. If symptoms symptoms persists, persists, consult a doctor. doctor. 

 •

Swallowing Small quantities do not have toxic effects. Large quantities may cause gastro-intestinal problems Do not induce vomiting, Administer ½ a litre of water or milk, Consult a doctor  

• • •

Extinguishers If the product is involved in a fire, use high volume water extinguishers. Environmental precautions Do not allow the product to pollute drains, surface water or the water table. Cleaning Soak up the product with earth, sand or other non-combustible material, and store in suitable waste containers.

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HD8 EURO 5



AD BLUE STORAGE 10 Litre drum

1000 litre IBC container

4500 litre MiniBulk container

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AD BLUE STORABILITY The following environmental conditions must be maintained for storage and transport: 1)

Recommended storage temperature –10 temperature –10 °C to i 30 °C. °C. The product begins to freeze at –11°C. Prolonged storage a temperature over 30°C 30°C causes hydrolysis with consequent formation of ammonia and increased pressure.

2)

Store the product away from direct sunlight (to prevent the growth of algae)

3)

Keep containers well closed to prevent contamination. Avoid contact with: strong corrosives, acids, alkalis, nitrates, nitrites and sodium/calcium hypochlorite.

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HD8 EURO 5

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EURO 5 Engines


CURSOR ENGINES EURO 5

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EURO 5 engines


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EURO 5 Engines


CONTENTS Page View of engine engine ....................... .................................. ...................... ....................... ....................... ...................... ....................... ....................... ................... ........ 5 Technical Technical denominatio denomination n ...................... ................................. ....................... ....................... ...................... ...................... ....................... .................. ...... 6 Principal Principal innovations................. innovations............................ ...................... ...................... ....................... ....................... ...................... ....................... ................. ..... 7 Technical Technical specificati specifications ons........... ...................... ....................... ....................... ...................... ...................... ....................... ....................... ................. ...... 8 Crankcase....... Crankcase.................. ....................... ....................... ...................... ...................... ....................... ....................... ...................... ....................... .................... ........ 9 Pistons Pistons ....................... .................................. ...................... ....................... ....................... ...................... ....................... ....................... ...................... .................. ......... .. 10 Cylinder Cylinder head................ head............................ ....................... ...................... ...................... ...................... ...................... ...................... ...................... .................. ....... 12 Valve train......................... train..................................... ....................... ...................... ....................... ....................... ...................... ....................... ....................... ............. 13 Valve springs springs ..................... ................................. ....................... ...................... ...................... ....................... ....................... ...................... ....................... ............ 14 Camshaft adjustment for euro 5 application............ ............................ .............. ............................ .......................... ............ 15 Fuel system system ...................... ................................. ...................... ....................... ....................... ...................... ....................... ....................... ...................... ............. .. 16 F3A/F3B F3A/F3B engine engine pump injector injector ...................... ................................. ..................... ..................... ...................... ...................... .................... ......... 17 Pressure Pressure damper damper ....................... .................................. ...................... ...................... ....................... ....................... ...................... ....................... ................ .... 19 Filter cartridge................... cartridge............................... ....................... ...................... ...................... ....................... ....................... ...................... ....................... .............. 20 Turbocharg Turbocharger er ..................... ................................. ....................... ...................... ...................... ....................... ....................... ...................... ....................... ............ 21 Lubrication Lubrication ....................... .................................. ...................... ...................... ....................... ....................... ...................... ....................... ....................... .............. ... 22 Control Control unit ...................... ................................. ....................... ....................... ...................... ....................... ....................... ...................... ....................... .............. .. 23 Sensors........ Sensors.................... ....................... ...................... ....................... ....................... ...................... ...................... ....................... ....................... ..................... ............ 27 SCR system system scheduled scheduled maintenanc maintenance e ...................... ................................. ...................... ...................... ...................... .................... ......... 29 NOx emissions emissions control control system system (SCR)..................... (SCR)................................ ....................... ....................... ...................... .................... ......... 30 SCR SYSTEM SYSTEM FUNCTIONA FUNCTIONAL L OUTLINE OUTLINE ...................... ................................ ..................... ...................... ..................... ................ ...... 34 SCR system system components components ..................... ................................ ..................... ..................... ...................... ...................... ...................... .................. ....... 36

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EURO 5 engines


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EURO 5 Engines


VIEW OF ENGINE

0051570t

0051571t

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EURO 5 engines

TECHNICAL SPECIFICATION

TYPE

F

3

B

E

3

6

8

PART NUMBER

1

A

*

F

0

0

1 -

Progressive production number Version number within the B.o.M. Exhaust Exhaust gas level level (euro 4) 4)

En ine ower ou out ut or to tor ue level Use (eg I = truck) truck) Fuel feed + injection (TCA, direct injection diesel engine) Number of cylinders Number of strokes and cylinders' position (eg 0 = 4 strokes, vertical) Engine Engine family evolution (also irrespective of the displacement) Engine range identification

HD8 EURO 5

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EURO 5 Engines


PRINCIPAL INNOVATIONS The main differences between Cursor Euro 5 engines and Cursor Euro 3 engines regard the following components: - Crankcase modified with new control unit suport; - Modified cylinder head; - pistons modified to fit lower thickness piston rings; - lower thinkness thinkness piston rings for oil and oil vapour consumption control; - use of new jets for pistons; - different profile profile injector injector pump pump control control cam on camshaft; camshaft; - Modified rocker shaft; - Modified damper flywheel - coaxial injector pump; - fuel system with pressure damper damper on fuel fuel delivery line from fuel filter to cylinder head; - EDC7 engine control unit; - EDC7 control unit programming software with OBD (On Board Board Diagnostic) and interface with VCM (Vehicle Control Module) and DCU (Dosing Control Unit); - engine wiring harness harness (head internal and engine external wiring); wiring); - New sensors; - heat exchanger exchanger with seat seat for oil pressure pressure and and temperature temperature sensor. sensor. - Modified turbo group; - SCR exhaust gas treatment system Part of the modifications have been introduced to comply with Euro 5 legislation, others to improve product performance.

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EURO 5 engines

TECHNICAL SPECIFICATIONS The differences between between the Cursor – Euro 5 and Cursor - Euro 3 engines are as follows:

ENGINE F2B

F3A

F3B

Compression ratio

16:1

16,5:1

16,5:1

Loadless idle speed [rpm]

600 ± 50

550 ± 50

550 ± 50

Loadless maximum speed [rpm]

2660 ± 50

2420 ± 50

2320 ± 50

Intake valve play [mm]

0,40 ± 0,05

0,40 ± 0,05

0,40 ± 0,05

Exhaust valve play [mm]

0,40 ± 0,05

0,50 ± 0,05

0,60 ± 0,05

Injection presure [bar]

1600

2000

2000

HD8 EURO 5

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EURO 5 Engines


CRANKCASE Mountings modified to fit the new control unit and mountings for new oil sprayers.

2 1

0051572

1. ECU support 2. External wiring

WIRING The engine is fitted with new internal wiring (injectors) and new external wiring (sensors and ECU).

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EURO 5 engines

PISTONS Lubricated by new sprayers incorporating a valve to permit passage of oil only above the threshold pressure of 1.7 bar. Lowering the pressure in the lubrication circuit assures optimal circuit filling and full lubrication of the most important parts. In the F3A and F3B engines, bushes have been inserted in the pistons The pistons have been modified to fit thinner rings to control oil and oil vapour consumption.

109080

CROSS-SECTION OF PNEUMATIC VALVE BUILT-IN TO PISTON OIL SPRAYERS

Aperture pressure = 1,7 bar

F2B Engines

109108

MAIN PISTON, PISTON RINGS AND PIN SPECIFICATONS

HD8 EURO 5

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EURO 5 Engines


F3A ENGINE

109045


F3B ENGINE

108837


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EURO 5 engines

CYLINDER HEAD On F3A/F3B engines the head is reinforced to support the increased internal pressure. The rocker cover has screening to reduce noise above all in the driver’s cabin.

0051573

1. Oil/Diesel fuel repellent black felt – 2. Low density porous layer with galss fibre reinforcing (10 mm thickness) – 3. Carbon black felt

HD8 EURO 5

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EURO 5 Engines


VALVE TRAIN The introduction of the new UIS N3.1 injectors (F3A/F3B engines) has also required changes to the injector cam profile on the camshaft. Lthe rocker bushes are reinforced with new springs due to the increased loading. The profile of the rocker has also been changed due to the different in size of the new injectors (F3A/F3B engine only).

0051574

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EURO 5 engines

VALVE SPRINGS The throttle type engine brake on the exhaust manifold requires greater spring loading than the previous type used for engines with decompression type engine brake, to prevent unwanted valve aperture during engine brake use. F2B Engines Valve closed

Valve open

109107

F3A Engine

109060

F3B engine

108842

HD8 EURO 5

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EURO 5 Engines


CAMSHAFT ADJUSTMENT FOR EURO 5 APPLICATION The new camshaft adjustments are: F2B: 4.90 ± 0.05 mm (as Euro3) F3A: 5.30 ± 0.05 mm F3B: 5.30 ± 0.05 mm

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HD8 EURO 5


EURO 5 engines

FUEL SUPPLY Fuel is delivered by the fuel pump through filter and pre-filter, to 6 injectors actuated by the camshaft through rockers and controlled by the electronic control unit.

CIRCUIT OF DELIVERY CIRCUIT OF RETURN 108847

FUEL SUPPLY DIAGRAM 1. Fuel filter – 2. Pressure damper – 3. Pressure regulator valve (start aperture at 5 bar) – 4. Fuel pump – 5. Fuel prefilter with primer pump – 6. Fuel recirculation valve from injectors built-in to fuel pump (start aperture at 3.5 bar) – 7. Control unit – 8. Heat exchanger exchanger – 9. Overpressure valve for fuel return to tank – 10. Pump injectors A. Fuel delivery to injectors – B. Fuel return to tank

The innovations in the fuel supply circuit regard:: - the introduction of a pressure pressure damper to reduce peak pressure in injector return piping -

increased volume of filter element

- modifications to control control unit, pump and and head head input piping

HD8 EURO 5

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EURO 5 Engines


F3A/F3B ENGINE PUMP INJECTOR

102405

CROSS SECTION OF UIS N3.1 INJECTOR Thanks to the increased injection pressure, the new UIS N3.1 injectors atomise fuel in the combustion chamber more efficiently, improving combustion and consequently reducing pollutant emissions in exhaust gases. The injectors used on CURSOR 8 EURO 5 engines are the same as used on the EURO 3 version

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EURO 5 engines

F3A/F3B injector replacement

102935

To remove the injector from the cylinder head, use tool 99342155 proceeding as follows: attach part (3) of tool 99342155 to the injector (4); to part (3) fit part (2), resting the latter on the cylinder head; tighten the nut (1) and extract the injector (4) f rom the cylinder head.

HD8 EURO 5

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EURO 5 Engines


PRESSURE DAMPER The fuel pressure damper on the piping between fuel filter and cylinder head serves to dampen the return back pressure due to the increased injection pressure.

0051575t

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EURO 5 engines

FILTER CARTRIDGE Increased volume filter cartridge introduced on F3A/F3B engines

0051576t

HD8 EURO 5

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EURO 5 Engines


TURBOCHARGER On F3B engies the exhaust manifold is reinforced to support the increased weight of the VGT. Modifications to the VGT turbines only regard internal parts. F2B engines have a new fixed pitch turbine with consequent modifications to the exhaust manifold due to the new turbine position. Engines with fixed pitch turbine are fitted with a CEB device (Combined Engine Brake), mounted on the turbine output to permit flow regulation in the various running conditions. The CEB functions like a traditional type engine brake (with betterfly valve on the exhaust) where the braking action is provided exclusively by backpressure of the gas in the exhaust manifold. F3B engine CEB with fixed pitch turbine

0051577t

F3B engine CEB with fixed pitch turbine

0051578t

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EURO 5 engines

LUBRICATION New oil pump to reduce flow-rate and pressure in lubrication circuit. Modified heat exchanger body to house new oil pressure/temperature sensor for the EDC7. New oil sprayers in pistons with built-in valve already described in pistons section. F2B engine oil pump

0051579t

F3A / F3B engine oil pump

0051580t

HD8 EURO 5

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EURO 5 Engines


CONTROL UNIT New EDC 7 UC31 control unit introduced to interface with the new electronics systems.

0051261t

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EURO 5 engines

Electroinjectors connector “A” 12

Colour code B black R red U blue W white P purple G green N brown Y yellow O orange

nero rosso blu bianco viola verde marrone giallo arancione

16

11

6

1

5

ECU Pin

F3A-F3B wire colour

1

-

Free

W

2

-

Free

R

3

B

Electronic injection electrovalve cylinders (4-5-6)

Y

4

-

Free

R

5

-

Free

G

6

Y

7

O

8

N

9

-

Free

P

10

-

Free

E

11

R

12

G

13

W

14

U

15

E

16

P

HD8 EURO 5

F3A-F3B function

F2B wire colour

Electronic injection electrovalve cylinder 2 Engine brake control electrovalve Engine brake control electrovalve

Engine brake control electrovalve cylinders (1-2-3) Engine brake control electrovalve cylinder 3 Electronic injection electrovalve cylinder 1 Electronic injection electrovalve cylinder 4 Electronic injection electrovalve cylinder 6 Electronic injection electrovalve cylinder 5

24

R U E

B E

102374

F2B function Injection electrovalve cylinder 1 Injection electrovalve cylinder 1 Injection electrovalve cylinder 2 Injection electrovalve cylinder 2 Injection electrovalve cylinder 3 Injection electrovalve cylinder 3 Injection electrovalve cylinder 4 Injection electrovalve cylinder 4 Injection electrovalve cylinder 5 Injection electrovalve cylinder 5 Injection electrovalve cylinder 6 Injection electrovalve cylinder 6

-

-

-

-

-

-

-

-

EURO 5 Engines


Sensors connector "C" 6

8 16

9

15

22

1

3

23 30

36

29

Colour code B R U W P G N Y O E K

black red blue white purple green brown yellow orange grey pink

nero rosso blu bianco viola verde marrone giallo arancione grigio rosa

4 5

102375

ECU Wire Function Pin colour Variable pitch turbine control electrovalve 1 N Free 2 Variable pitch turbine control electrovalve 3 B Free 4÷8 9 W Camshaft flywheel sensor 10 R Camshaft flywheel sensor 11 ÷ 14 15 K Coolant fluid temperature sensor 16 Free Free 17 18 O/B Fuel temperature sensor 19 B Flywheel sensor 20 N Turbocompressor speed sensor 21 ÷ 22 Free 23 W Flywheel sensor 24 N Engine oil/pressure sensor ground 25 W Air pressure/temperature sensor sensor power supply 26 Y Coolant fluid temperature sensor Oil temperature signal from engein oil pressure/temperature sensor 27 O/B 28 U Oil pressure signal from engein oil pressure / temperature sensor 29 Free Turbocompressor speed sensor 30 W 31 Free Engine oil pressure / temperature sensor power supply 32 O Air temperature / pressure sensor power supply supply 33 R 34 G Pressure signal from air temperature / pressure sensor 35 W/R Fuel temperature sensor Temperature signal from air pressure / temperature sensor 36 O

25

HD8 EURO 5


EURO 5 engines

Frame connector "B" 71 89

72

54

6

11

1 7 12

53

Pin ECU 2 3 5 6 8 9 10 11 12 26 27 28 29 34 35 40 55 58 68 75 85 89

35

18

Wire 7151 7151 0150 0150 7151 7151 0150 0150 0094 5173 5174 0173 5163 GN/Ve WS/Bi 8015 9966 0043 8173 9164 0163 2298

HD8 EURO 5

36

17

Function Positive +30 Positive +30 Ground Ground Positive +30 Positive +30 Ground Ground Pre-warming enable relay ground Intake air relative humidity sensor signal Intake air temperature sensor signal Intake air temperature and humidity sensor ground EDC system diagnostics power switch (fitting) CAN L ECB line CAN H ECB line +15 Engine brake and/or stop control electrovalve power supply Ground Intake air temperature and humidity sensor power supply EDC pre-warming relay activation signal EDC diagnostics switch power supply EDC diagnostics control unit K line

26

102376

EURO 5 Engines


SENSORS New sensors fitted for the EDC7 control unit

FLYWHEEL REVS SENSOR

0051582t

0051583t

CAMSHAFT REVS SENSOR

27

HD8 EURO 5


EURO 5 engines

0051581t

OIL TEMPERATURE / PRESSURE SENSOR

HD8 EURO 5

28

EURO 5 Engines


SCR SYSTEM SCHEDULED MAINTENANCE

m k y r 0 e 0 v 0 . E 0 0 1

Check on AdBlue system using diagnostics instrument Replacement of AdBlue filter/prefilter

CURSOR 8

m k y r 0 e 0 v 0 . E 0 5 1

X

m k y r 0 e 0 v 0 . E 0 0 3

X

CURSOR 10/13

X

X

CURSOR 8

X

X

CURSOR 10/13

X

X

29

HD8 EURO 5


EURO 5 engines

NOX EMISSIONS CONTROL SYSTEM (SCR) Overview To limit the emissions of nitrogen oxides (Nox) in exhaust gases to within the limits required by Euro 4, with low fuel consumption, the vehicle has been fitted with a system for post-treating these substances in exhaust gases, consisting essentially of an electronically controlled catalytic oxidiser. By means of then SCR process (Selective Catalytic Reduction) the system converts nitrogen oxies (NOX) into inert compounds: free nitrogen (N2) and water vapour (H2O). Description The system consists essentially of: - a reagent reagent solution reservoir (water – urea: urea: AdBlue) with level level indicator; - an H2O switching valve; - a pump module; - a mixing and injection module (dosing module); - a catalytic converter; - two exhaust exhaust gas temperature sensors sensors upstream upstream and downstream of the cataytic converter; converter; - a humidity sensor sensor mounted on the engine engine air intake piping downstream of the air filter. The system is electronically managed by the DCU (Dosing Control Unit) built-in to the pump module, which, according to engine speed, torque delivered, exhaust gas temperature, quantity of nitrogen oxides and intake air humidity, regulates the flow-rate of AdBlue solution injected into the system. The pump module draws the reagent solution from the reservoir and delivers it under pressure to the dosing module for injection into the exhaust pipe upstream of the catalytic converter. The first phase of the process takes place in the first part of the converter: by effect of exhaust gas temperature, the reagent solution vaporises and by hydrolysis converts into ammonia (NH3) and carbon dioxide (CO2), at the same time, evaporation of the solution causes exhaust gas temperature to drop to close to the ideal temperature for the process. The exhaust gas with added ammonia and at the correct reaction temperature enters the catalytic converter where the second phase of the process takes place: reacting with the oxygen in the exhaust gas, the ammonia transforms into free litrogen (N2) and water vapour (H2O).

HD8 EURO 5

30

EURO 5 Engines


Nox emissions control system – functional principle

31

HD8 EURO 5


EURO 5 engines

List of SCR system electrical components Name 42XXX3 47XXX 72069 78266 78267 84XXX 85140 85141 85142 85143 85144 85150 85161 72021

Description AdBlue solution pressure sensor Ad Blue solution temperature sensor 16-pin OBD coupling (On-Board Diagnostics) Dosing module electrovalve with SCR Engine water circulation electrovalve for warming UREA reservoir with SCR. Volumetri e/pump with pressure regulator and recirculation valve Electronic control for SCR sensor pump module Catalytic converter with SCR output temperature sensor UREA reservoir level and temperature sensor Catalytic converter intake temperature sensor NOX nitrogen oxide densor (if present) EDC control unit Intake air relative humidity and temperature sensor 30-pin diagnostics socket

SCR system component locations aboard vehicle (see following page) 1. 2. 3. 4. 5. 6. 7. 8. 9.

Water – urea solution reservoir: AdBlue AdBlue level indicator Pump module H2O switching valve Dosing module Catalytic converter Intake air humidity sensor Exhaust gas gas temperature sensor upstream upstream of converter Exhaust gas gas temperature sensor downstream downstream of converter

HD8 EURO 5

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EURO 5 Engines


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EURO 5 engines

SCR SYSTEM FUNCTIONAL OUTLINE

r e x i M

e l u d o m p m u P

r e t l i f n i a M

e n a r p b m m u e p M

t n e v r i o v r e s e R

s r e t l i f e r P

HD8 EURO 5

34

e l u d o m g n i s o D l l i r g h t i w r i o v r e s e r e u B d A

EURO 5 Engines


Functional logic

Components MV 1 4/2 multi-way valve MV 2 MV 3 MV 4 p1 p

t° 1 t° 2 t

t° 3 t° 4 Q

Q

NOX NOX

Function magnetic AdBlue system filling-draining

Dosing valve Cooling valve Reservoir heater valve

AdBlue dosing module Drainage AdBlue heating with engine coolant AdBlue pressure sensor AdBlue system pressure measurement AdBlue reservoir AdBlue temperature temperature measurement AdBlue dosin module AdBlue temperature temperature measurement Cat. intake temperature Catalytic converter gas temperature Cat. output temperature Catalytic converter gas temperature AdBlue reservoir level AdBlue level in reservoir sensor NOX q.ty sensor: at present Application foreseen as from not foreseen 2007

35

HD8 EURO 5


EURO 5 engines

SCR SYSTEM COMPONENTS Reservoir

1

The reservoir contains the reducing substance required by the SCR process, consisting of a solution of 35% urea and water, known as AdBlue. The reservoir has a level indicator (1) that also includes the AdBlue fluid heating coil. The AdBlue filler cap is fitted with a magnet, which when detected by the filler pistol permits opening of the piston nozzle. This prevents the possibility of mistakenly filling the fuel tank with AdBlue. On the other hand, the diameter of the AdBlue filler does not fit a fuel pump nozzle. This prevents the possibility of mistakenly filling the AdBlue tank with fuel.

HD8 EURO 5

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EURO 5 Engines


AdBlue level indicator

0051311t

1. AdBlue liquid intake pipe - 2. AdBlue fluid return pipe 3. Hot engine coolant input pipe - 4. NTC sensor5. Hot engine coolant output pipe - 6. Float 7. AdBlue liquid heating coil

102308

CIRCUIT DIAGRAM) The AdBlue level indiator consists of a series of resistors, a float, and NTC temperature sensor and a heating coil to warm the liquid in low temperature conditions. The device transmits variations in current proportional to resistance (determined by the position of the float in relation to the AdBlue liquid level) to the control unit.

37

HD8 EURO 5


EURO 5 engines

AdBlue heating system using engine coolant fluid Engine coolant is sent via the magnetic switch valve to the pump module through specific piping, then on to the dosing module and finally to the AdBlue reservoir, to prevent crystallization of the urea at low temperature. The conditions for activating the valve are defined by the engine control unit.

From cooling system

Magnetic valve Dosing module

Pump module

To cooling system Delivery AdBlue reservoir

HD8 EURO 5

38

Return

EURO 5 Engines


Switching valve

108127

1. Coolant intake - 2. Coolant output - 6. Electrical connection The NC type valve permits heating of the AdBlue reservoir and piping by hot coolant from the engine. The NTC sensor (above) controls the switching valve that, according to temperature, closes or opens delivery of hot engine coolant to the heating coil.

39

HD8 EURO 5


EURO 5 engines

Pump module

108128

1. AdBlue return piping to reservoir - 2. AdBlue return piping from dosing module - 3. AdBlue solution output - 4. AdBlue solution intake - 5. Electrical connection 6. DCY control unit connector - 7. Filter - 8. Prefilter

HD8 EURO 5

40

EURO 5 Engines


View of connector – cable input side

0051246t

Ref.

1 2 3 4 5 6 11 12 14 15 17 18 19 23 24 25 26 28 29 31 33

Description

Engine coolant circulation electrovalve positive Urea filter output heating power +30 power supply +30 power supply CAN - H line (ECB) CAN - L line (ECB) Urea dosing module control Dosing module electrovalve power supply with SCR Ground Ground Ground wire for catalytic converter input temperature sensor Urea Urea rese reserv rvoi oirr leve levell sens sensor or sign signal al cabl cable e Urea Urea reserv reservoir oir level level and temper temperatu ature re sensor sensor ground ground Urea reservoir heating electrovalve ground +15 positive Catalytic converter temperature sensor ground wire Catalytic converter output temperature sensor signal Catalytic converter input temperature sensor cable Urea reservoir temperature sensor signal cable SCR control unit diagnostics line “K” Urea filter output heating control

41

Wire colour code

7542 7546 7540 7540 Bianco Verde 9541 7541 0000 0000 0544 6543 6543 0543 0543 9542 8540 0541 6541 6544 6542 2257 9546

HD8 EURO 5


EURO 5 engines

Dosing module

108129

1. Ad Blue intake - 2. Electrical connection - 3. Ad Blue output The module doses the AdBlue solution for delivery to the exhaust pipe upstream of the catalytic converter.

HD8 EURO 5

42

EURO 5 Engines


Catalytic converter

3

1

2

With sound absorbing material, the catalytic converter (1) takes the place of the traditional exhaust muffler. Inside the converter, the nitrogen oxides in the exhaust gas react with ammonia and are converted into free nitrogen and water vapour. The catalytic converter is fitted with temperature sensors upstream (2) and downstream (3).

43

HD8 EURO 5


EURO 5 engines

Exhaust gas temperature sensor

102303

102304

CIRCUIT DIAGRAM 1. Supply voltage - 2. Variable output voltage - 3. Connector 4. Grey signal cable - 5. White ground cable - 6. Sensor This serves to transmit converter input and output exhaust gas temperature values to the control unit that calculates the quantity of urea to inject into the system.

HD8 EURO 5

44

EURO 5 Engines


Humidity sensor

102311

1. Temperature - 2. Ground - 3. Percentage humidity - 4. Power supply Located on the output from the air filter, this serves to deliver the percentage humidity value of the intake air to the control unit, to t o calculate nitrogen oxide emissions.

102312

ELECTRICAL BLOCK DIAGRAM 1. Ground - 2. Temperature Temperature - 3. Power supply supply - 4. Percentage humidity - A. Sample frequency generator - B. Reference oscillator - C. NTC temperature sensor D. Low pass filter amplifier

45

HD8 EURO 5

Ad BLUE

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