Sistema HEUI

1. Service Training
MALAGA
Large Track Type Tractors
1 ENGINE CONTROL 3400 HEUI
1. Components Layout
2. Operation
3. Testing & Adjusting
Adolfo
May 1997

2. Page:
1-2
HIGH PRESSURE OIL MANIFOLD
High Pressure
40 to 210 BAR
Oil Pump
HEUI FUEL SYSTEM
CHAPTER : 3400 HEUI
Regulator Fuel Return Line
Pressure
Large Track Type Tractors
Control
Valve
Engine System
Fuel
Filter
ECM
Oi Fuel
lS Trans
Oil Oil u Vehicle Pump
Oil
Filter Cooler Pump
m System
p
LOW PRESSURE 3 BAR Fuel Tank

3. Large Track Type Tractors
CHAPTER : 3400 HEUI
HEUI FUEL SYSTEM
The electronic components in the HEUI fuel system are very similar to those used in other EUI systems.
However, in the HEUI system, the injectors are not actuated by a camshaft
The seven major types of components in the HEUI fuel system are:
• Hydraulic Supply Pump Group containing:
- High pressure hydraulic pump
- Pump control valve
- Transfer pump
• ECM
• Throttle Control
• Speed/Timing Sensor
• Injector
• Temperature Sensor
• Pressure Sensor
Page: 1-3

4. Large Track Type Tractors
CHAPTER : 3400 HEUI
INJECTOR COMPONENTS
SPACER
SLEEVE
ARMATURE
VALVE
VALVE BODY SOLENOID
SHIM
BARREL
ADAPTER
PISTON WASHER
UPPER FUEL SEAL
PLUNGER
FUEL INLET
CHECK VALVE
PIN
SLEEVE
SPACER
LOWER FUEL SEAL
CHECK
NOZZLE
Page: 1-4

5. Large Track Type Tractors
CHAPTER : 3400 HEUI
INJECTION CYCLE
Page: 1-5

6. Large Track Type Tractors
CHAPTER : 3400 HEUI
POPPET VALVE OPEN
ARMATURE
SCREW
POPPET
SPRING
Page: 1-6

7. Large Track Type Tractors
CHAPTER : 3400 HEUI
DRAIN CYCLE
Page: 1-7

8. Large Track Type Tractors
CHAPTER : 3400 HEUI
POPPET VALVE CLOSED
POPPET VALVE
SOLENOID
ARMATURE
INLET EXHAUST
VALVE SEAT VALVE SEAT
Page: 1-8

9. Large Track Type Tractors
CHAPTER : 3400 HEUI
NOZZLE GROUP
NOZZLE GROUP
REVERSE FLOW
CHECK VALVE
CHECK VALVE
FUEL
ATOMIZATION
Page: 1-9

10. Large Track Type Tractors
CHAPTER : 3400 HEUI
PRIME RATE SHAPING
CROSS SECTION
OF PLUNGER
FINAL
START OF INJECTION PRESSURE DROP PRESSURE INCREASE
INJECTION
RATE
START OF END OF
INJECTION DURATION INJECTION
TIME (MILLISECONDS)
Page: 1-10

11. Large Track Type Tractors
CHAPTER : 3400 HEUI
VENTING INTERNAL LEAKS
INTENSIFIER
PISTON
INTENSIFIER
PISTON SEAL
BARREL
VENTING
CHECK VALVE
During the normal injection cycle, the pressure of the oil supplied to the top of the intensifier
piston can increase to 22800 kPa (3300 psi). A seal is installed to minimize leakage past the
piston.
Some oil which is necessary for lubrication of the intensifier piston may pass the seal and settle
momentarily below the piston.
Also, a small amount of fuel may leak past the plunger and barrel. This fuel will settle
momentarily in the cavity below the intensifier piston.
If the fluids which accumulate below the piston are not vented, a hydraulic lock could occur. As
the piston moves down, the fuel is ejected past the barrel ball check valve to the low pressure
inlet. The check valve then closes during the plunger and piston upstroke.
Page: 1-11

12. Large Track Type Tractors
CHAPTER : 3400 HEUI
INJECTOR CHECK VALVES
BARREL GROUP NOZZLE GROUP
FUEL INLET
CHECK VALVE
VENTING
CHECK VALVE
REVERSE FLOW
CHECK VALVE
NOZZLE
CHECK VALVE
FUEL
ATOMIZATION
The Fuel Inlet Check Valve allows fuel to fill the barrel below the plunger, but closes as the plunger
moves down and pressure increases.
The Venting Check Valve vents fluids from below the intensifier piston.
The Reverse Flow Check Valve prevents combustion gasses from flowing back through the injector
from the nozzle.
The Nozzle Check Valve controls valve opening pressure by preventing the flow of fuel through the
nozzle holes until sufficient pressure is available to lift the valve from its seat
Page: 1-12

13. Large Track Type Tractors
CHAPTER : 3400 HEUI
PRESSURE CONTROL
INJECTION PRESSURE
HEUI
MECHANICALLY ACTUATED
FUEL SYSTEM
IDLE
ENGINE SPEED
Page: 1-13

14. Page:
1-14
TO LUBE
SYSTEM HEUI
HYDRAULIC
TEMPERATURE
SENSOR
COLD START
OIL FLUID MANIFOLD
RESERVOIR OIL PRESSURE HYDRAULIC PASSAGE
SENSOR
COOL DOWN FUEL HYDRAULIC
HYDRAULIC CIRCUIT TEMPERATURE PRESSURE
SUPPLY SENSOR SENSOR
PUMP
OIL GROUP
FILTER FLUID MANIFOLD
HYDRAULIC PASSAGE
LOW PRESSURE OIL (HYDR.) SUPPLY
CHAPTER : 3400 HEUI
Large Track Type Tractors
PUMP
CONTROL HEUI
VALVE ECM
OIL
COOLER
FUEL
TRANSFER SECONDARY PRESSURE
PUMP FUEL REGULATING
LUBE OIL
PUMP FILTER VALVE
PRIMARY
FUEL FILTER
WATER
SEPARATOR
OIL
SUMP FUEL TANK

15. Page:
1-15
TO LUBE
SYSTEM HEUI
HYDRAULIC
TEMPERATURE
SENSOR
COLD START
OIL FLUID MANIFOLD
RESERVOIR OIL PRESSURE HYDRAULIC PASSAGE
SENSOR
COOL DOWN FUEL HYDRAULIC
HYDRAULIC CIRCUIT TEMPERATURE PRESSURE
SUPPLY SENSOR SENSOR
PUMP
OIL GROUP
FILTER FLUID MANIFOLD
HYDRAULIC PASSAGE
PUMP
CONTROL HEUI
VALVE ECM
OIL
COOLER
FUEL
TRANSFER
SECONDARY PRESSURE
PUMP
FUEL REGULATING
LUBE OIL
FILTER VALVE
PUMP
PRIMARY
CHAPTER : 3400 HEUI
FUEL FILTER
WATER
SEPARATOR
OIL
HIGH PRESSURE HYDRAULICS
SUMP FUEL TANK
Large Track Type Tractors

16. Large Track Type Tractors
CHAPTER : 3400 HEUI
REVERSE FLOW CHECK VALVE
(END VIEW)
SEAT
FROM
PUMP
SEAT
CHECK
SPRING
VALVE BLOCK
FITTING
INJECTORS
TO
Page: 1-16

17. Large Track Type Tractors
CHAPTER : 3400 HEUI
REVERSE FLOW CHECK VALVE
The hydraulic supply pump group has two outlet ports, each connected by steel tubes to a hydraulic
supply manifold. An integral reverse flow check valve is located in each outlet port.
This view shows that pressure surges travelling back from the injectors toward the pump will cause the
check valve to close and block any interference between the banks. In normal operation, the valve will
oscillate at high frequency as it blocks the pressure surges.
The valve check fits loosely on the shaft to allow oil flow from the reservoir during the cooling process.
If the check valves were not in the system, pressure surges between the banks would cause erratic
operation of the injectors by adversely affecting timing. The pressure surge causes the poppet valves to
open prematurely. This condition would start
fuel injection earlier than normal, thereby advancing the timing.
Page: 1-17

18. Page:
TO LUBE
1-18
SYSTEM HEUI
HYDRAULIC
TEMPERATURE
SENSOR
COLD START
OIL FLUID MANIFOLD
RESERVOIR OIL PRESSURE HYDRAULIC PASSAGE
SENSOR
COOL DOWN FUEL HYDRAULIC
HYDRAULIC CIRCUIT TEMPERATURE PRESSURE
SUPPLY SENSOR SENSOR
PUMP
OIL GROUP
FILTER FLUID MANIFOLD
HYDRAULIC PASSAGE
PUMP
CONTROL HEUI
VALVE ECM
OIL
COOLER
FUEL
TRANSFER
SECONDARY
CHAPTER : 3400 HEUI
PUMP PRESSURE
LUBE FUEL FILTER REGULATING
OIL
PUMP (2 MICRON) VALVE
PRIMARY
FUEL FILTER
LOW PRESSURE FUEL SUPPLY
WATER
SEPARATOR
Large Track Type Tractors
OIL
SUMP FUEL TANK

19. Large Track Type Tractors
CHAPTER : 3400 HEUI
LOW PRESSURE FUEL SUPPLY
On a HEUI equipped engine, the lubrication pump has two functions:
1. Provides lubrication to the engine
2. Provides low pressure charge oil to the HEUI hydraulic pump
The engine lubrication pump has been enlarged to provide the required increase in flow.
During normal operation conditions, oil is pressurized between 5000 and 21500 kPa (725 and 3100 psi)
by the high pressure hydraulic pump to actuate the injectors.
The pressure regulating valve regulates fuel pressure between 310 and 415 kPa (45 and 60 psi).
The ratio of fuel between combustion and fuel return to the tank is about 1:3 (i.e. four times the volume
required for combustion is supplied to the system for combustion and injector cooling purposes).
Page: 1-19

20. Page:
HIGH PRESSURE
HYDRAULIC OIL
1-20
INJECTOR OIL INJECTOR CLAMP
ADAPTER
JUMPER TUBE
ROCKER ARM BASE
INJECTOR
LUBE OIL PASSAGE
HIGH PRESSURE
HYDRAULIC PASSAGE
CHAPTER : 3400 HEUI
FLUID SUPPLY
INJECTOR FLUID FLOW
MANIFOLD
Large Track Type Tractors
CYLINDER HEAD
INJECTOR SLEEVE
CYLINDER HEAD
LOW PRESSURE
FUEL SUPPLY
COOLANT
CYLINDER BLOCK
METAL WASHER

21. Page:
1-21
INJECTOR
UPPER INJECTOR UPPER SLEEVE
O-RING SEAL O-RING SEAL
CYLINDER HEAD
INJECTOR SLEEVE
FLUID SUPPLY
MANIFOLD LOWER SLEEVE
O-RING SEAL
INJECTOR FUEL SUPPLY
CHAPTER : 3400 HEUI
Large Track Type Tractors
LOW PRESSURE
FUEL SUPPLY
CYLINDER
HEAD
METAL-TO- METAL
LOWER INJECTOR CONTACT
O-RING SEAL

22. Page:
COMPENSATOR
1-22
PRIMING PORT VALVE
ORIFICE VALVE BASE
DRAIN PASSAGE
TRANSFER PUMP
RESERVOIR
HEUI PUMP
CHAPTER : 3400 HEUI
Large Track Type Tractors
SWASHPLATE

23. Page:
1-23
TO LEFT OIL TO RIGHT OIL
TO LUBE COLD START MANIFOLD
RESERVIOR MANIFOLD
SYSTEM
DISPLACEMENT
CONTROL PISTON
CHECK VALVE
PRESSURE
LIMITER
SUPPLY PUMP SPOOL
START-UP
CHAPTER : 3400 HEUI
SOLENOID LOAD
Large Track Type Tractors
(ENERGIZED) SENSING
SPOOL
OIL SUMP
PUMP
CONTROL
VALVE
PUMP
CASE DRAIN

24. Page:
PRESSURE LIMITER SPOOL
1-24
ORIFICE
PUMP CONTROL
VALVE LOAD SENSING SPOOL
CHECK VALVE
FROM DISPLACEMENT
CONTROL PISTON
START-UP
CHAPTER : 3400 HEUI
DRAIN ORIFICE
Large Track Type Tractors
TO CASE DRAIN
TO
CASE
DRAIN
REVERSE FLOW
CHECK VALVES

25. Large Track Type Tractors
CHAPTER : 3400 HEUI
START-UP
The displacement of the pump is controlled to maintain the desired operating pressure at the flow rate
required by the injectors. The displacement is regulated by an electro-hydraulic control.
Displacement of the pump is varied by pivoting the swashplate from
0 degrees to a maximum angle of 15.5 degrees. When the engine is not running, the swashplate is at the
maximum angle. During operation, the displacement control piston adjusts the swashplate position to
meet the system flow demand.
During initial cranking, the swashplate is at full displacement until the supply pressure increases to 6200
kPa (900 psi). The spring at the end of the load sensing spool regulates this pressure. Then, the
specification programmed into the ECM for normal cranking will override this pressure. Until this point,
the control valve solenoid is fully energized for the pressure increase.
During START-UP, pressure from the pump enters the compensator assembly. The Pump Control Valve
is energized for quick pressure build-up.
Pressure is felt at both ends of the Load Sensing Spool. The spool is shifted to the right and oil from the
Displacement Control Piston is vented to case drain. The swashplate is at maximum angle.
The drain orifice below the Pump Control Valve provides a small amount of restriction to improve valve
stability
Page: 1-25

26. Page:
1-26
TO LEFT OIL TO RIGHT OIL
TO LUBE COLD START MANIFOLD
RESERVIOR MANIFOLD
SYSTEM
DISPLACEMENT
CONTROL PISTON
CHECK VALVE
PRESSURE
LIMITER
SUPPLY PUMP SPOOL
DESTROKE
CHAPTER : 3400 HEUI
LOAD
SOLENOID SENSING
Large Track Type Tractors
(DE-ENERGIZED) SPOOL
OIL SUMP
PUMP
CONTROL
VALVE
PUMP
CASE DRAIN

27. Page:
1-27
PRESSURE
LIMITER SPOOL
ORIFICE
PUMP
CONTROL VALVE
LOAD SENSING
SPOOL
DESTROKE
CHAPTER : 3400 HEUI
CHECK VALVE
Large Track Type Tractors
TO DISPLACEMENT
CONTROL PISTON
DRAIN ORIFICE
TO CASE DRAIN

28. Large Track Type Tractors
CHAPTER : 3400 HEUI
DESTROKE
After the engine starts and pressure increases, the ECM will signal the control valve to match the actual
with the desired pressure by momentarily de-energizing and then regulating the current flow to the pump
control valve solenoid.
The decrease in current applied to the pump control valve solenoid lowers the pressure required to
initiate flow through the pump control valve. This lower cracking pressure on the pump control valve
creates a force imbalance on the load sensing spool, causing the spool to move toward the spring end of
the compensator. This spool motion connects the displacement control piston to pump output flow,
allowing the swashplate to decrease the displacement of the pump. The decreased displacement lowers
the pump output to the pressure level required by the ECM.
During DESTROKE, the ECM momentarily de-energizes the Pump Control Valve causing a pressure
drop in the spring chamber of the Load Sensing Spool.
Unbalanced pressures force the spool to the left, allowing the oil to enter the Displacement Control
Piston and move the swashplate toward minimum angle.
Page: 1-28

29. Page:
1-29
TO LEFT OIL TO RIGHT OIL
TO LUBE COLD START MANIFOLD MANIFOLD
SYSTEM RESERVIOR
DISPLACEMENT
CONTROL PISTON
CHECK VALVE
PRESSURE
LIMITER
SUPPLY PUMP SPOOL
UPSTROKE
CHAPTER : 3400 HEUI
LOAD
SOLENOID SENSING
Large Track Type Tractors
(ENERGIZED) SPOOL
OIL SUMP
PUMP
CONTROL
VALVE
PUMP
CASE DRAIN

30. Page:
1-30
PRESSURE
LIMITER SPOOL
ORIFICE
PUMP
CONTROL VALVE
LOAD SENSING
SPOOL
CHECK VALVE
UPSTROKE
CHAPTER : 3400 HEUI
Large Track Type Tractors
FROM
DISPLACEMENT
CONTROL PISTON
DRAIN ORIFICE
TO CASE DRAIN

31. Large Track Type Tractors
CHAPTER : 3400 HEUI
UPSTROKE
As the load on the engine increases and higher pressure is required, the ECM will signal the control
valve to increase pressure by increasing the current flow to the pump control valve solenoid.
The increase in current applied to the pump control valve solenoid raises the pressure setting of the
pump control valve. This higher pressure at the pump control valve creates a force imbalance on the
load sensing spool, causing the spool to move toward the supply signal line end of the compensator.
This spool motion vents the displacement control piston to case drain, allowing the spring to move the
swashplate to increase the displacement of the pump. The increased displacement raises the pump
output to the desired pressure level required by the ECM.
As the load is applied to the engine, the ECM increases current to the Pump Control Valve.
Pressure is felt at both ends of the Load Sensing Spool. The spool moves to the right (due to spring
force) and oil from the Displacement Control Piston is vented to case drain, which allows the swashplate
to momentarily go to maximum angle and build pressure quickly.
Page: 1-31

32. Page:
1-32
TO LEFT OIL TO RIGHT OIL
TO LUBE COLD START MANIFOLD
RESERVIOR MANIFOLD
SYSTEM
DISPLACEMENT
CONTROL PISTON
PRESSURE
LIMITER
SUPPLY PUMP SPOOL
PRESSURE LIMITER OPERATION
CHAPTER : 3400 HEUI
LOAD
SOLENOID SENSING
Large Track Type Tractors
(DE-ENERGIZED) SPOOL
PLUGGED
ORIFICE
OIL SUMP
PUMP
CONTROL
VALVE
PUMP
CASE DRAIN

33. Page:
1-33
PRESSURE LIMITER
SPOOL
PUMP
CONTROL VALVE ORIFICE
RESTRICTION
LOAD SENSING
SPOOL
PRESSURE LIMITER OPERATION
CHAPTER : 3400 HEUI
CHECK VALVE
Large Track Type Tractors
TO
DISPLACEMENT
CONTROL PISTON
DRAIN ORIFICE
TO CASE DRAIN

34. Large Track Type Tractors
CHAPTER : 3400 HEUI
PRESSURE LIMITER OPERATION
If the load sensing spool or pump control valve sticks or otherwise malfunctions to create higher than
desired operating pressures, the maximum pressure limiter spool is utilized. In this schematic, a plugged
orifice is simulated. (This example represents an actual condition which was caused by debris being
introduced during a field replacement of the compensator valve.)
The Pressure Limiter Spool directs pump outlet flow to the displacement control piston and reduces the
stroke of the pump if the system pressure exceeds 25600 kPa (3700 psi).
During these conditions, the pump will develop 24800 to 25600 kPa (3600 to 3700 psi) maximum
pressure, regardless of the desired hydraulic pressure. The Check Engine Lamp will be ON, indicating a
fault.
A Pump Control Valve Test will verify the control valve operation. This test enables the technician to
manually ramp the pressure up and down using the ET service tool. This procedure will also be useful
when evaluating the condition of the hydraulic system.
If the supply pressure exceeds 25600 kPa (3700 psi), the force acts on the Pressure Limiter Spool and
shifts it to the left. This movement compresses the spring and allows oil to unseat the check valve and
pressurize the displacement control piston. The swashplate moves to minimum angle to decrease flow
and limit system pressure.
Page: 1-34

35. Page:
1-35
NO CURRENT FLOW
FROM LOAD
COIL POPPET SENSING SPOOL
ASSEMBLY VALVE ADAPTER SEAL SEAT CAGE VALVE
EDGE
FILTER
STOP STATOR
PUMP CONTROL VALVE
CHAPTER : 3400 HEUI
Large Track Type Tractors
VALVE TO SPRING
ARMATURE SOLENOID PIN SHELL RING BLOCK CASE DRAIN RETAINER

36. Page:
1-36
HIGH CURRENT FLOW
FROM LOAD
COIL POPPET SENSING SPOOL
ASSEMBLY VALVE ADAPTER SEAL SEAT CAGE VALVE
EDGE
FILTER
STOP STATOR
PUMP CONTROL VALVE
CHAPTER : 3400 HEUI
Large Track Type Tractors
VALVE TO SPRING
ARMATURE SOLENOID PIN SHELL RING BLOCK CASE DRAIN RETAINER

37. Page:
1-37
8 OR 12
INJECTORS
ADEM II
ELECTRONIC
CONTROL
ENGINE MODULE DISCONNECT SWITCH
(ECM) GROUND
HARNESS BOLT
24 V
MAIN KEY
MACHINE 15 AMP POWER RELAY SWITCH
HARNESS BREAKER
PUMP
CONTROL VALVE
MACHINE
HYDRAULIC INTERFACE
PRESSURE SENSOR CONNECTOR
TDC SERVICE
PRIMARY PROBE ACCESS THROTTLE
SPEED/TIMING SENSOR ACCELERATOR
SENSOR PEDAL
SECONDARY
COMPONENTS DIAGRAM
CHAPTER : 3400 HEUI
SPEED/TIMING SENSOR THROTTLE BACK-UP, ELEVATED LOW IDLE ENABLE,
AND GROUND LEVEL SHUTDOWN (2) SWITCHES
Large Track Type Tractors
COOLANT TEMP. SENSOR TURBO INLET PRESSURE SENSOR
FAN CONTROL VALVE
TURBO OUTLET PRESS. SENSOR
FAN SPEED SENSOR
FAN
ATMOSPHERIC PRESS. SENSOR
CAT DATA LINK
OIL PRESSURE SENSOR ELECTRONIC SERVICE TOOL
EPTC II TRANSMISSION CONTROL
HYDRAULIC TEMP. SENSOR
AUTO RETARDER CONTROL
FUEL TEMPERATURE SENSOR
INSTRUMENT
PANEL
COOLANT FLOW SWITCH

38. Large Track Type Tractors
CHAPTER : 3400 HEUI
SENSORS - ANALOG & DIGITAL
ANALOG SENSORS
- HYDRAULIC PRESSURE
- COOLANT TEMPERATURE
- ATMOSPHERIC PRESSURE
- TURBOCHARGER INLET PRESSURE
- TURBOCHARGER OUTLET PRESSURE
- LUB. OIL PRESSURE
- HYDRAULIC TEMPERATURE
- FUEL TEMPERATURE
DIGITAL SENSORS
- THROTTLE POSITION
- PUMP CONTROL VALVE SIGNAL
- EXHAUST TEMPERATURE (not
installed on machine engines at
this time)
Page: 1-38

39. Large Track Type Tractors
CHAPTER : 3400 HEUI
SYSTEM POWER SUPPLIES
The HEUI system has six power supplies with various voltages as shown.
EXTERNAL POWER SUPPLY
ECM power supply 24 Volts
INTERNAL POWER SUPPLIES
Speed/Timing Sensor power supply 12.5 Volts
Injector power supply 105 Volts
Analog Sensor power supply 5 Volts
Digital Sensor power supply 8 Volts
Pump Control Valve power supply 0 to 24 Volts
The power supply to the ECM and the system is drawn from the 24-Volt machine battery. The principle
components in this circuit are:
- Battery
- Key Start Switch
- Main Power Relay
- 15 Amp Breaker
- Ground Bolt
- ECM Connector (P1/JI)
- Machine Interface Connector (J3/P3)
If the supply voltage exceeds 32.5 Volts or is less than 9.0 Volts, a diagnostic code is logged. (See the
Troubleshooting Guide for complete details on voltage event logging.)
NOTE: The ground bolt is the only power supply component mounted on the engine.
Page: 1-39

40. Large Track Type Tractors
CHAPTER : 3400 HEUI
LOGGED EVENTS
Logged events are abnormal to the operation of the engine (for example: high temperature, low pressure
or excessive engine speed). These conditions would not normally be caused by an electronic problem.
Some of the parameters listed in this presentation are used in the ET events list. They are:
- High coolant temperature above 107°C (225°F)
- Loss of coolant flow
- Low (lubrication) oil pressure (according to the oil pressure map)
- Abnormal injection actuation hydraulic pressure (low or high)
- Injection actuation pressure system fault
- User defined shutdown (if installed)
- Air inlet restriction (if installed)
- Engine overspeed histogram
- Low fuel pressure (industrial engine only)
Events are not logged if an electronic fault is detected.
Passwords are required to clear events. This process would normally be performed during an engine
overhaul. At other times, the events would be left as a record of the engine history prior to overhaul time.
Page: 1-40

41. Large Track Type Tractors
CHAPTER : 3400 HEUI
SYSTEM LIMITS & DERATE
FUEL SYSTEM LIMITS
MAXIMUM HORSEPOWER
TORQUE LIMIT ( Determines torque rise characteristics)
FUEL RATIO CONTROL ( Limits fuel until sufficient boost )
COLD MODE ( Limits fuel to control white smoke )
CRANKING FUEL ( Limits fuel during cranking )
FUEL SYSTEM DERATES
FUEL SYSTEM DERATES
AUTOMATIC ALTITUDE COMPENSATION
AUTOMATIC ALTITUDE COMPENSATION
( Altitude derate)
( Altitude derate)
AUTOMATIC FILTER COMPENSATION
AUTOMATIC FILTER COMPENSATION
( Derate for air filter restriction installed )
( Derate for air filter restriction if if insatalled
At 6.25 kPa (30 inc of water) the engine will
ENGINE 2% of its powerDERATE until a maxi 20%
derate WARNING per 1 kPa
Event is logged if exeeds 30 inch of water )
( Derates for LOW OIL PRESSURE, HIGH COOLANT TEMP
not install in HEUI at the time)
ENGINE WARNING DERATE
( Derates for LOW OIL PRESSURE , HIGH COOLANT TEMP
not installed yet on HEUI)
Page: 1-41

42. Page:
REF
1-42
TDC
SECONDARY REF TDC SINGLE
4 50/50 TOOTH
SPEED/TIMING
SENSOR
TDC CYLINDER No. 1
3 8
REF PRIMARY
SPEED/TIMING
SENSOR
TDC
REF
TIMING
TIMING WHEEL
CHAPTER : 3400 HEUI
1 CALIBRATION
6 RANGE ± 10°
Large Track Type Tractors
TDC REF
TIMING WHEEL
ROTATION TDC
REF
5 2
7 REF
TDC
REF TDC

43. Page:
1-43
TIMING GEAR TOOTH TABLE
TABLE PWM DUTY CYLINDER
ENTRY CYCLE REFERENCE
A 80 % NONE IDENTIFIED
B 80 %
C 80 %
D 80 %
E 80 %
F 80 %
G 80 %
H 50 %
CRANKING
CHAPTER : 3400 HEUI
Large Track Type Tractors
80/20 % 80/20 % 80/20 % 80/20 % 80/20 % 80/20 % 50/50%
A B C D E F G H
TIMING WHEEL ROTATION

44. Page:
1-44
TIMING GEAR TOOTH TABLE
TABLE PWM DUTY CYLINDER
ENTRY CYCLE REFERENCE
A 80 % NO
B 80 % CYL NO. 3
C 80 % NO
D 80 % NO
E 80 % CYL NO. 4
F 80 % NO
G 80 % NO
H 50 % CYL NO. 8
AFTER PATTERN RECOGNITION
CHAPTER : 3400 HEUI
Large Track Type Tractors
TIMING WHEEL ROTATION
A B C D E F G H
CYL NO. 3 CYL NO. 3 CYL NO. 4 CYL NO. 4 CYL NO. 8
REFERENCE TDC REFERENCE TDC REFERENCE
EDGE EDGE EDGE

45. Page:
TIMING GEAR TOOTH TABLE
1-45
TABLE PWM DUTY CYLINDER
ENTRY CYCLE REFERENCE
A 80 % NO
B 80 % CYL NO. 3
C 80 % NO
D 80 % NO
E 80 % CYL NO. 4
F 80 % NO
G 80 % NO
H 50 % CYL NO. 8
TIMING WHEEL ROTATION
NORMAL OPERATION
CHAPTER : 3400 HEUI
Large Track Type Tractors
A B C D E F G H
62° BTDC (EEPROM) 62° BTDC (EEPROM)
DES TIMING DES TIMING
DELAY NO. 3 DELAY NO. 4
INJECTION INJECTION
ASSUMED ASSUMED
TDC TDC
CYL NO. 3 CYL NO. 4
CYL NO. 3 ACTUAL TDC CYL NO. 4 ACTUAL TDC
(REFERENCE) (CALIBRATED) (REFERENCE) (CALIBRATED)

46. Page:
1-46
TIMING
WHEEL
REFERENCE EDGE TO TDC DISTANCE
REFERENCE
EDGE ASSUMED ACTUAL
TIMING CALIBRATION
CHAPTER : 3400 HEUI
CYL. NO. 1 TDC CYL. NO. 1 TDC
Large Track Type Tractors
-10° +10° TIMING
REFERENCE
TIMING CALIBRATION ± 10° OFFSET
SENSOR SIGNAL
MAXIMUM TIMING REFERENCE OFFSET ± 10 DEGREES

47. Large Track Type Tractors
CHAPTER : 3400 HEUI
INJECTION CURRENT WAVEFORM
5
4
TIME (MILLISECONDS)
HOLD-IN PEAK CURRENT
3
ONE CYCLE
2
PULL-IN PEAK CURRENT
1
0
CURRENT FLOW
Page: 1-47

48. Large Track Type Tractors
CHAPTER : 3400 HEUI
POPPET VALVE MOVEMENT
5
4
CURRENT
TIME (MILLISECONDS)
3
2
POPPET
1
LIFT
0
CURRENT FLOW
Page: 1-48

49. Page:
1-49
POPPET INJECTION
LIFT RATE
CURRENT FLOW
CURRENT
WAVEFORM & RESP. CHARACTERISTICS
CHAPTER : 3400 HEUI
Large Track Type Tractors
DURATION
0 1 2 3 4 5
START OF TIME (MILLISECONDS) END OF
INJECTION INJECTION