Systems Operation

Testing and Adjusting

2206D-E13TA Industrial Engine

Table of Contents

Piston Ring Groove - Inspect............. ............. 53

Connecting Rod Bearings - Inspect........ ........ 53

Main Bearings - Inspect................. ................. 53

Cylinder Block - Inspect................. ................. 53

Cylinder Liner Projection - Inspect......... ......... 53

Flywheel - Inspect...................... ..................... 56

Flywheel Housing - Inspect .............. .............. 57

Vibration Damper - Check ............... ............... 59

Systems Operation Section

General Information..................... ..................... 4

Electronic Control System Components...... ..... 6

Cleanliness of Fuel System Components..... .... 8

Fuel System........................... ........................... 9

Air Inlet and Exhaust System............. ............. 16

Lubrication System..................... .................... 19

Cooling System ....................... ....................... 20

Basic Engine.......................... ......................... 24

Electrical System...................... ...................... 25

Electrical System

Battery - Test.......................... ......................... 60

Charging System - Test ................. ................. 60

Electric Starting System - Test............ ............ 61

Index Section

Testing and Adjusting Section

Index................................ ............................... 62

Fuel System

Fuel System - Inspect................... .................. 28

Air in Fuel - Test....................... ....................... 28

Electronic Unit Injector - Adjust............ ........... 29

Electronic Unit Injector - Test............. ............. 30

Finding Top Center Position for No. 1 Piston. . 31

Fuel Quality - Test...................... ..................... 31

Fuel System - Prime.................... ................... 32

Fuel System Pressure - Test.............. ............. 33

Gear Group (Front) - Time............... ............... 35

Air Inlet and Exhaust System

Air Inlet and Exhaust System - Inspect...... ..... 36

Turbocharger - Inspect .................. ................. 37

Exhaust Temperature - Test.............. .............. 39

Engine Crankcase Pressure (Blowby) - Test. . 39

Compression - Test..................... .................... 40

Engine Valve Lash - Inspect/Adjust........ ........ 40

Lubrication System

Engine Oil Pressure - Test............... ............... 42

Engine Oil Pump - Inspect............... ............... 44

Excessive Bearing Wear - Inspect......... ......... 44

Excessive Engine Oil Consumption - Inspect. 45

Increased Engine Oil Temperature - Inspect . . 45

Cooling System

Cooling System - Check (Overheating)..... ..... 46

Cooling System - Inspect................ ................ 48

Cooling System - Test................... .................. 49

Water Temperature Regulator - Test........ ....... 51

Water Pump - Test..................... ..................... 51

Basic Engine

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Systems Operation Section

i06196289

General Information

The following model views show typical features of

the engine. Due to individual applications, your

engine may appear different from the illustrations.

Illustration 1

g03812155

Typical example

(1) Refrigerant compressor

(2) Alternator

(3) Belt tensioner

(5) Vibration damper

(6) Coolant intake

(7) Oil cooler

(9) Engine oil filter

(10) Turbocharger

(4) Fuel transfer pump

(8) Secondary fuel filter

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Systems Operation Section

Illustration 2

g03812156

Typical example

(11) Engine front lifting eye

(12) Coolant outlet

(16) Flywheel housing

(17) Flywheel

(21) Oil gauge (dipstick)

(22) Air compressor

(13) Water temperatureregulator housing

(14) Engine rear lifting eye

(18) Starting motor

(19) Air intake

(23) Location for oil filler

(24) Crankcase breather

(15) Electronic Control Module (ECM)

(20) Oil drain valve

The Electronic Unit Injector (EUI) provides increased

control of the timing and increased control of the fuel

air mixture. Engine rpm is controlled by adjusting the

injection duration. Engine timing is controlled by the

precise control of fuel injection timing.

Starting the Engine

The engines ECM will automatically provide the

correct amount of fuel in order to start the engine. Do

not hold the throttle down while the engine is

cranking. If the engine fails to start in 30 seconds,

release the starting switch. Allow the starting motor to

cool for 2 minutes before the starting motor is used

again.

The Electronic Control Module (ECM) monitors the

components of the engine during operation. In the

event of a component failure, an event code will be

logged in the ECM. The electronic service tool can be

connected to the engine in order to read any logged

faults. Intermittent faults are logged and stored in

memory.

Cold Mode Operation

The ECM will set the cold start strategy when the

coolant temperature is below 18 °C (64 °F).

When the cold start strategy is activated, low idle rpm

will be increased to 1000 rpm and the power of the

engine will be limited.

Cold mode operation will be deactivated when any of

the following conditions have been met:

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•   Coolant temperature reaches 18 °C (64 °F).

•   The engine has been running for 14 minutes.

Cold mode operation varies the fuel injection amount

and the timing for white smoke cleanup. The engine

operating temperature is usually reached before the

walk-around inspection is completed. The engine will

idle at the programmed low idle rpm in order to be put

in gear.

After the cold mode is completed, the engine should

be operated at low rpm until normal operating

temperature is reached. The engine will reach normal

operating temperature faster when the engine is

operated at low rpm and low-power demand.

i06196504

Electronic Control System

Components

The illustrations within the following sections are

typical location of the sensors or electrical

components for an industrial engine. Specific engines

may appear different due to differences in

applications.

Illustration 3

g03863738

Typical example

(1) Coolant temperature sensor

(2) Inlet manifold pressure sensor

(3) Inlet air temperature sensor

(4) Electronic Control Module (ECM)

(5) Oil pressure sensor

(6) Camshaft speed timing sensor

(7) Atmospheric pressure sensor

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Systems Operation Section

Illustration 4

g03863739

Typical example

(8) Crankshaft speed timing sensor

(9) Fuel temperature sensor

(10) Fuel pressure sensor

The electronic control system is integrally designed

into the fuel system and the air inlet and exhaust

system of the engine in order to electronically control

the fuel delivery and the injection timing. The

electronic control system provides increased timing

control and fuel air ratio control in comparison to

conventional mechanical engines. Injection timing is

achieved by precise control of injector firing time, and

engine rpm is controlled by adjusting the firing

duration. The Electronic Control Module (ECM)

energizes the solenoid in the unit injector in order to

start the injection of fuel. Also, the ECM de-energizes

the unit injector solenoids in order to stop injection of

fuel. Refer to Systems Operation, Testing and

Adjusting, “Fuel System” for a complete explanation

of the fuel injection process.

•   Voltage

•   Frequency

•   Pulse width

The variation of the signal is in response to a change

in some specific system of the equipment. The ECM

sees the input sensor signal as information about the

condition, environment, or operation of the

equipment.

An electronic control module (ECM) receives the

input signals. Electronic circuits inside the control

component evaluate the signals from the input

components. These electronic circuits also supply

electrical energy to the output components of the

system. The electrical energy that is supplied to the

output components is based on predetermined

combinations of input signal values.

The engine uses the following types of electronic

components:

•   Inputs

An output component is one that is operated by a

control module. The output component receives

electrical energy from the control component. The

output component uses that electrical energy in one

of two ways. The output component can use that

electrical energy in order to perform work. The output

component can use that electrical energy in order to

provide information.

•   Controls

•   Outputs

An input component is one that sends an electrical

signal to the ECM. The signal that is sent varies in

one of the following ways:

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i06196634

Only use fuel that is free from contamination, that

conforms to the specifications in the Operation and

Maintenance Manual, “Fluid Recommendations” Fuel

Specifications.

Cleanliness of Fuel System

Components

Cleanliness of the Engine

NOTICE

It is important  to maintain extreme cleanliness when

working on the fuel  system, since even tiny particles

can cause engine or fuel system problems.

The entire engine should be washed with a high-

pressure water system. Washing the engine will

remove dirt and loose debris before a repair on the

fuel system is started. Ensure that no high-pressure

water is directed at the seals for the injectors or any

electrical connector.

Environment

When possible, the service area should be positively

pressurized. Ensure that the components are not

exposed to contamination from airborne dirt and

debris. When a component is removed from the

system, the exposed fuel connections must be closed

off immediately with suitable sealing plugs. The

sealing plugs should only be removed when the

component is reconnected. The sealing plugs must

not be reused. Dispose of the sealing plugs

immediately after use. Contact your nearest Perkins

distributor in order to obtain the correct sealing plugs.

New Components

High-pressure lines are not reusable. New high-

pressure lines are manufactured for installation in one

position only. When a high-pressure line is replaced,

do not bend or distort the new line. Internal damage

to the pipe may cause metallic particles to be

introduced to the fuel.

All new fuel filters, high-pressure lines, tube

assemblies, and components are supplied with

sealing plugs. These sealing plugs should only be

removed in order to install the new part. If the new

component is not supplied with sealing plugs then the

component should not be used.

The technician must wear suitable rubber gloves. The

rubber gloves should be disposed of immediately

after completion of the repair in order to prevent

contamination of the system.

Refueling

In order to refuel the diesel fuel tank, the refueling

pump and the fuel tank cap assembly must be clean

and free from dirt and debris. Refueling should take

place only when the ambient conditions are free from

dust, wind, and rain.

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i06196641

Fuel System  

Illustration 5

g01721176

Typical example

(1) Primary speed/timing sensor

(2) Secondary speed/timing sensor

(3) Injectors

(10) Engine oil pressure sensor

(11) Engine coolant temperature sensor

(12) Inlet air temperature sensor

(13) Fuel temperaturesensor

(14) Engine coolant level sensor

(15) Power Take Off (PTO) ON/OFF switch

(16) PTO SET/RESUME switch

(17) Timing calibration connector

(18) Throttle position sensor

(19) SAE J1939 Data Link

(20) Warning lamp

(21) Diagnostic lamp

(22) Programmableoutputs

(23) Keyswitch

(24) Battery

(25) Electronic Control Module (ECM)

(26) Fuel manifold (rail)

(4) Fuel pump

(5) Secondary fuel filter

(6) Primary fuel filter and water separator

(7) Fuel tank

(8) Fuel pressure regulator

(9) Atmospheric pressure sensor

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Systems Operation Section

The Electronic Unit Injector system consists of the

following systems: the mechanical system and the

electronic system. The mechanical system is made

up of the low-pressure fuel supply system and the

electronic unit injectors. The electronic system

provides complete electronic control of all engine

functions. The electronic control system consists of

the following three types of components: input,

control and output.

There are five major components of the Electronic

Unit Injector fuel system:

•   Electronic unit injectors

•   Fuel transfer pump

•   ECM

•   Sensors

•   Solenoids

The Electronic Unit Injectors produce fuel injection

pressures up to 207000 kPa (30000 psi). The

Electronic Unit Injectors also fire up to 19 times per

second at rated speed. The fuel transfer pump

supplies the injectors by drawing fuel from the tank

and by pressurizing the system between 60 and 125

PSI. The ECM is a powerful computer which controls

all major engine functions. Sensors are electronic

devices which monitor engine performance

parameters. Engine performance parameters

measure pressure, temperature, and speed. This

information is sent to the ECM via a signal. Solenoids

are electronic devices which use electronic currents

from the ECM to change engine performance. An

example of a solenoid is the Injector solenoid.

Low Pressure Fuel System

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Illustration 6

g01721234

(4) Fuel pump

(5) Secondary fuel filter

(6) Primary fuel filter and water separator

(7) Fuel tank

(8) Fuel pressure regulator

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Systems Operation Section

The low-pressure fuel system supplies fuel from the

fuel tank to the injectors. The low-pressure fuel

system has four basic functions:

information to the ECM by a signal voltage. Actuators

are electronic devices which use electrical currents

from the ECM to change engine performance. An

example of an actuator is an injector solenoid.

•   Supply fuel for combustion

Temperature Regulator for the fuel (If

Equipped)

•   Supply fuel in order to cool the injectors.

•   Remove air from the fuel.

Later models will not have a temperature regulator for

the fuel.

•   Warm the fuel in the fuel tank.

The major parts in a low-pressure fuel system consist

of the following components:

The fuel regulator valve is located in one of the return

fuel lines. The fuel line runs from the fuel filter base to

the fuel transfer pump. The fuel regulator valve is

controlled by the temperature of the fuel. The valve is

in the open position at temperatures below 21 °C

(70 °F). The valve closes at temperatures above

27 °C (80 °F).

•   Fuel tank

•   Fuel transfer lines

•   Primary fuel filter or water separator

•   Fuel transfer pump

The temperature regulator for the fuel is used to

supply the injectors with warm fuel during cold

operation. Fuel is delivered to the injectors by a fuel

passage in the cylinder head. The injectors are

supplied with an excess of fuel. The excess fuel

removes heat from the injectors. This heated fuel will

mix with the cold fuel in the fuel tank. The fuel

regulator valve in the return fuel line mixes fuel from

the fuel tank with the excess fuel that is returning to

the fuel tank. The warm fuel increases injector life.

•   Secondary fuel filter

•   Fuel priming pump

•   Fuel pressure regulator valve

•   Fuel regulator valve

The electronic unit injectors, the fuel transfer pump,

the ECM, sensors, and solenoids are part of the low-

pressure fuel system.

Electronic Controls

The electronic control system provides complete

electronic control of all engine functions. The

In the low-pressure fuel system, the fuel is pulled from

the fuel tank to the primary fuel filter or to the water

separator. The primary fuel filter removes large debris

from the fuel before the fuel flows into the transfer

pump. The fuel transfer pump is a gear pump that

contains a pressure relief valve. Fuel flows from the

outlet port of the transfer pump to the secondary fuel

filter. The 2 micron filter removes small abrasive

contaminants from the fuel system, which can cause

damage to the unit injectors.

electronic control system consists of the following

three types of components: input, control and output.

Sensors monitor engine operating conditions. This

information is sent to the ECM. The ECM has three

main functions. The ECM provides power for the

engine electronics and monitors input signals from

the engine sensors. The ECM also acts as a governor

to control engine rpm. The ECM stores active faults,

logged faults, and logged events. The Personality

Module is the software in the ECM which contains the

specific maps that define power, torque, and RPM of

the engine. The ECM sends electrical current to the

output components in order to control engine

operation. The ECM has the following connectors:

two 70 pin harness connectors, one engine harness

connector and one vehicle harness connector. The

vehicle harness connects the ECM to the engine

control portion of the vehicle harness. The engine

control portion includes the following components.

The fuel filter base contains a hand operated fuel

priming pump. The fuel priming pump removes air

from the system when a fuel filter has been changed

or a unit injector has been changed. The priming

pump pulls fuel from the tank, around the transfer

pump and into the filter. The transfer pump pushes

fuel through the supply passage in the cylinder head

and back to the tank.

The fuel pressure regulator consists of a check valve

that is spring loaded. The pressure relief valve opens

at approximately 414 to 862 kPa (60 to 125 psi).

When the engine is in the off position and the fuel

pressure drops below 414 kPa (60 psi), the check

valve closes. The check valve closes in order to

prevent the fuel in the cylinder head from draining

back into the fuel tank. Retaining the fuel in the head

maintains a supply of fuel for the injectors during

start-up.

•   Transmission

•   Brake

•   Clutch switches

•   PTO switch

•   Data links

•   Check engine light

•   Warning light

The ECM controls major engine functions. Sensors

are electronic devices that monitor engine

performance parameters. The pressure sensor, the

temperature sensor, and the speed sensor provide

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Systems Operation Section

•   Engine retarder switch

•   Speedometer

energized. The ECM sends a 90 V signal to the

solenoid for energizing the solenoid. By controlling

the timing of the 90 V signal, the ECM controls

injection timing. By controlling the duration of the 90 V

signal, the ECM controls the injected fuel amount.

•   Tachometer

•   Cooling fan solenoid

Injection timing is determined by engine rpm, and

other engine data. The ECM senses the top center

position of cylinder number 1 from the signal that is

provided by the engine speed sensor. The ECM

decides when the injection should occur relative to

the top center position. The ECM provides the signal

to the unit injector at the desired time.

The following features are part of the electronic

control system:

•   Cold start strategy

•   Oil pressure

Unit Injector Mechanism

•   Coolant temperature warning indicator

•   Automatic altitude compensation

•   Variable injection timing

•   Electronic engine speed governing

These features result in the following items: precise

engine speed control, very little smoke, faster cold

starting and built-in engine protection.

The ECM consists of the following two main

components: the ECM and the personality module.

The ECM is a computer and the personality module is

the software for the computer. The personality

module contains the operating maps. The operating

maps define the following characteristics of the

engine:

•   Horsepower

•   Torque curves

•   Rpm

Illustration 7

g01451028

Typical examples of electronic unit injector fuel

systems.

•   Other characteristics

(27) Unit injector

The ECM, the personality module, the sensors, and

the unit injectors work together in order to control the

engine. The ECM, the personality module, the

sensors, and the unit injectors cannot control the

engine alone.

(28) Adjusting nut

(29) Rocker arm assembly

(30) Pushrod

The unit injector pressurizes the fuel. The correct

amount of fuel is then injected into the cylinder block

at precise times. The ECM determines the injection

timing and the amount of fuel that is delivered. The

unit injector is operated by a camshaft lobe and a

rocker arm. The camshaft has three camshaft lobes

for each cylinder. Two lobes operate the inlet and

exhaust valves, and the other lobe operates the unit

injector mechanism. Force is transferred from the unit

injector lobe on the camshaft through the lifter to the

pushrod (30). The force of the pushrod is transferred

through rocker arm assembly (29) and to the top of

the unit injector. The adjusting nut (28) allows setting

of the unit injector adjustment. Refer to Systems

Operation/Testing and Adjusting, “Electronic Unit

Injector - Adjust” for the proper setting of the unit

injector adjustment.

The ECM determines a desired rpm that is based on

the following criteria:

•   Throttle signal

•   Certain diagnostic codes

•   Vehicle speed signal

The ECM maintains the desired engine rpm by

sensing the actual engine rpm. The ECM calculates

the fuel amount that needs to be injected in order to

achieve the desired rpm.

Fuel Injection Timing and Delivery

Unit Injector

The ECM controls the injected fuel amount by varying

the signals to the unit injectors. The unit injectors will

inject fuel ONLY if the unit injector solenoid is

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Illustration 8

g01451031

(31) Solenoid

(32) Tappet

(33) Plunger

(34) Barrel

(35) Nozzle assembly

Operation of the Electronic Unit Injector

Illustration 9

g00942799

Pre-injection

The operation of the Electronic Control Unit (EUI)

consists of the following four stages: Pre-injection,

Injection, End of injection and Fill. Unit injectors use a

plunger and barrel to pump high-pressure fuel into the

combustion chamber. Components of the injector

include the tappet, the plunger, the barrel, and nozzle

assembly. Components of the nozzle assembly

include the spring, the nozzle check, and a nozzle tip.

The cartridge valve is made up of the following

components: solenoid, armature, poppet valve and

poppet spring.

(A) Fuel supply pressure

(B) Injection pressure

(C) Moving parts

(D) Mechanical movement

(E) Fuel movement.

Pre-injection metering starts with the injector plunger

and the injector tappet at the top of the fuel injection

stroke. When the plunger cavity is full of fuel, the

poppet valve is in the open position and the nozzle

check is in the open position. Fuel leaves the plunger

cavity when the rocker arm pushes down on the

tappet and the plunger. Fuel flow that is blocked by

the closed nozzle check valve flows past the open

poppet valve to the fuel supply passage in the

The injector is mounted in an injector bore in the

cylinder head which has an integral fuel supply

passage. The injector sleeve separates the injector

from the engine coolant in the water jacket. Some

engines use a stainless steel sleeve. The stainless

steel sleeve fits into the cylinder head with a light

press fit.

cylinder head. If the solenoid is energized, the poppet

valve remains open and the fuel from the plunger

cavity continues flowing into the fuel supply passage.

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Systems Operation Section

Illustration 10

g00942798

Illustration 11

g00942801

Injection

End of injection

(A) Fuel supply pressure.

(B) Injection pressure

(C) Moving parts

(A) Fuel supply pressure

(C) Moving parts

(D) Mechanical movement

(E) Fuel movement.

Injection is continuous while the injector plunger

moves in a downward motion and the energized

solenoid holds the poppet valve closed. When

injection pressure is no longer required, the ECM

stops current flow to the solenoid. When the current

flow to the solenoid stops, the poppet valve opens.

The poppet valve is opened by the fuel injector spring

and the fuel pressure. High-pressure fuel can now

flow around the open poppet valve and into the fuel

supply passage. This results in a rapid drop in

injection pressure. When the injection pressure drops

to approximately 24 MPa (3500 psi), the nozzle

check closes and injection stops. This is the end of

injection.

To start injection, the ECM sends a current to the

solenoid on the cartridge valve. The solenoid creates

a magnetic field which attracts the armature. When

the solenoid is energized, the armature assembly will

lift the poppet valve so the poppet valve contacts the

poppet seat. This is the closed position. Once the

poppet valve closes, the flow path for the fuel that is

leaving the plunger cavity is blocked. The plunger

continues to push fuel from the plunger cavity and the

fuel pressure builds up. When the fuel pressure

reaches approximately 34.5 MPa (5000 psi), the

force of the high-pressure fuel overcomes the spring

force. This holds the nozzle check in the closed

position. The nozzle check moves off the nozzle seat

and the fuel flows out of the injector tip. This is the

start of injection.

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i06196481

Air Inlet and Exhaust System  

Illustration 13

g01046036

Air inlet and exhaust system schematic

(1) Inlet to the engine

(2) Aftercooler core

(3) Inlet air line

(4) Exhaust outlet from turbocharger

(5) Turbine side of turbocharger

(6) Compressor side of turbocharger

(7) Air cleaner

The engine components of the air inlet and exhaust

system control the quality of air and the amount of air

that is available for combustion. The components of

the air inlet and exhaust system are the following

components:

•   Air cleaner

•   Turbocharger

•   Aftercooler

Illustration 12

g00942802

•   Cylinder head

Fill

•   Valves and valve system components

•   Piston and cylinder

•   Exhaust manifold

(A) Moving parts

(B) Mechanical movement

(C) Fuel movement.

When the plunger reaches the bottom of the barrel,

fuel is no longer forced from the plunger cavity. The

plunger is pulled up by the tappet and the tappet

spring. The upward movement of the plunger causes

the pressure in the plunger cavity to drop below fuel

supply pressure. Fuel flows from the fuel supply

passage around the open poppet and into the plunger

cavity as the plunger travels upward. When the

plunger reaches the top of the stroke, the plunger

cavity is full of fuel and fuel flow into the plunger

cavity stops. This is the beginning of pre-injection.

The turbocharger compressor wheel pulls inlet air

through the air cleaner and into the air inlet. The air is

compressed and this causes the air to become hot.

The air flows through aftercooler core (2) and the

temperature of the compressed air lowers. This helps

to provide increased horsepower output. Aftercooler

core (2) is a separate cooler core that is mounted in

front of the engine radiator. The engine fan causes

ambient air to move across both cores. This cools the

turbocharged inlet air and the engine coolant.

Air is forced from the aftercooler into inlet manifold

(1). The air flow from the inlet port into the cylinders is

controlled by inlet valves.

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Turbocharger

Illustration 14

g00615497

Air inlet and exhaust system

(2) Aftercooler core

(4) Exhaust outlet

(5) Turbine side of turbocharger

(6) Compressor side of turbocharger

(8) Exhaust manifold

(9) Exhaust valve

(10) Inlet valve

(11) Air inlet

Illustration 15

g00291085

Turbocharger

Each cylinder has two inlet valves (10) and two

exhaust valves (9) in the cylinder head. The inlet

valves open on the inlet stroke. When the inlet valves

open, compressed air from the inlet port within the

inlet manifold is pushed into the cylinder. The inlet

valves close when the piston begins the compression

stroke. The air in the cylinder is compressed and the

fuel is injected into the cylinder when the piston is

near the top of the compression stroke. Combustion

begins when the fuel mixes with the air. The force of

combustion pushes the piston on the power stroke.

The exhaust valves open and the exhaust gases are

pushed through the exhaust port into exhaust

manifold (8). After the piston finishes the exhaust

stroke, the exhaust valves close and the cycle begins

again.

(4) Air inlet

(5) Compressor housing

(6) Compressor wheel

(7) Bearing

(8) Oil inlet port

(9) Bearing

(10) Turbine housing

(11) Turbine wheel

(12) Exhaust outlet

(13) Oil outlet port

(14) Exhaust inlet

Turbocharger (3) is mounted to exhaust manifold (2)

of the engine. All of the exhaust gases go from the

exhaust manifold through the turbocharger.

The exhaust gases enter the turbocharger and the

turbine wheel is turned. Because the turbocharger

turbine wheel is connected by a shaft to the

turbocharger compressor wheel, the turbine wheel

and the compressor wheel turn at very high speeds.

The rotation of the compressor wheel pulls clean air

through the compressor housing air inlet. The action

of the compressor wheel blades causes a

compression of the inlet air. This compression allows

a larger amount of air to enter the engine. With more

air in the engine, the engine is able to burn more fuel.

The overall effect is an increase in power.

Exhaust gases from the exhaust manifold flow into

the turbine side of turbocharger (5). The high

temperature exhaust gases cause the turbocharger

turbine wheel to turn. The turbine wheel is connected

to the shaft that drives the compressor wheel.

Exhaust gases from the turbocharger pass through

exhaust outlet (4), through a muffler, and through an

exhaust stack.

Bearing (7) and bearing (9) in the turbocharger use

engine oil that is under pressure for lubrication. The

lubrication for the bearings flows through oil inlet port

(8) and into the inlet port in the center section of the

turbocharger cartridge. The oil exits the turbocharger

through oil outlet port (13). The oil then returns to the

engine oil pan through the oil drain line for the

turbocharger.

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18

UENR0632

Systems Operation Section

Valve System Components

Illustration 16

g01086490

(1) Rocker arm

(2) Pushrod

(3) Valve bridge

(4) Valve spring

(5) Valve

(6) Lifter

The valve system components control the flow of inlet

air into the cylinders and out of the cylinders during

engine operation. The valve mechanism also

operates the fuel injector.

The camshaft must be timed to the crankshaft in

order to get the correct relation between the piston

movement and the valve movement.

The camshaft has two camshaft lobes for each

cylinder. The lobes operate the inlet and exhaust

valves. As the camshaft turns, lobes on the camshaft

cause lifters (6) to move pushrods (2) up and down.

Upward movement of the pushrods against rocker

arms (1) results in downward movement (opening) of

valves (5).

Each cylinder has two inlet valves and two exhaust

valves. The valves are actuated at the same time by

a valve bridge (3). Valve springs (4) close the valves

when the lifters move down.

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UENR0632

19

Systems Operation Section

i06196479

Lubrication System  

Illustration 17

g01417920

Lubrication system schematic

(1) Piston cooling jets

(6) Oil filter bypass valve

(7) Main bearings

(8) Signal line

(9) Primary engine oil filter

(10) Engine oil pump

(11) Oil cooler bypass valve

(12) Engine oil cooler

(13) Oil pan

(14) High-pressurerelief valve

(15) Oil pump bypass valve

(2) Main oil gallery in cylinder block

(3) Engine pressure sensor

(4) Oil flow to valve mechanism

(5) Camshaft journals

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20

UENR0632

Systems Operation Section

i02918835

Cooling System  

Coolant Flow

Illustration 18

g01417942

Right side view of engine

(9) Primary engine oil filter

(10) Engine oil pump

(12) Engine oil cooler

The lubrication system supplies 110 °C (230 °F)

filtered oil at approximately 275 kPa (40 psi) at rated

engine operating conditions. Oil pump bypass valve

(15) is controlled by the engine oil manifold pressure,

rather than the oil pump pressure. The engine oil

manifold pressure is independent of the pressure

drop that is caused by the engine oil filter and the

engine oil cooler.

Illustration 19

g01085911

Cooling system schematic

(1) Cylinder head

(2) Expansion tank

(3) Return manifold

(4) Cylinder liners

(5) Temperatureregulator housing

(6) Radiator

Oil cooler bypass valve (11) maintains the engine oil

temperature to 110 °C (230 °F). High-pressure relief

valve (14), which is located in the filter base, protects

the filters and other components during cold starts.

The opening pressure of the high-pressure relief

valve is 695 kPa (100 psi). The opening pressure of

the oil filter bypass valve is 170 kPa  (25 psi). Engine

oil pressure sensor (3) is part of the engine protection

system.

(7) Water pump

(8) Engine oil cooler

The water pump is gear-driven. The water pump is

located on the right hand side of the engine. The

water pump supplies the coolant for the engine

cooling system. The coolant is supplied to the

following components:

•   Cylinder head (1)

The turbocharger cartridge bearings are lubricated by

the oil supply line from the main oil gallery, and the oil

drain line returns the oil flow to the sump.

•   Cylinder liners (4)

•   Engine oil cooler (8)

•   Air compressor (not shown)

•   Coolant conditioner element (not shown)

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UENR0632

21

Systems Operation Section

The coolant is pumped through engine oil cooler (9).

The coolant then flows to the supply manifold. The

supply manifold, which is located in the cylinder

block, distributes coolant around the upper portion of

the cylinder liners. At each cylinder, the coolant flows

from the cylinder liner to the cylinder head. The

cylinder head is divided into single cylinder cooling

sections. In the cylinder head, the coolant flows

across the center of the cylinder and across the

injector seat boss. At the center of the cylinder, the

coolant flows around the injector sleeve over the

exhaust port. The coolant then exits into return

manifold (3). The return manifold collects the coolant

from each cylinder and the return manifold directs the

flow to temperature regulator housing (5). When the

coolant temperature regulator is in the closed

position, the coolant flows through the coolant

temperature regulator. This allows the coolant to flow

directly back to the water pump for recirculation by

bypassing the radiator. When the coolant temperature

regulator is in the open position, the coolant is

directed through the radiator and back to the water

pump inlet.

Supply Manifold

Cooling is provided for only the portion of the cylinder

liner above the seal in the cylinder block. The coolant

enters the cylinder block at each cylinder through slits

in the supply manifold. The supply manifold is an

integral casting in the cylinder block. The coolant

flows around the circumference of the cylinder liner

and into the cylinder head through a single drilled

passage for each liner. The coolant flow is split at

each cylinder liner so that 60 percent flows around

the cylinder liner and the remainder flows directly to

the cylinder head.

Illustration 20

g01098799

Right side view of engine

(3) Return manifold

(5) Temperature regulator housing

(7) Water pump

(8) Engine oil cooler

Water pump (8) pulls the coolant from the bottom of

radiator. The water pump is located on the right hand

side of the front timing gear housing.

Temperature Reg, ulator Housing

The water pump impeller rotates at 1.37 times the

engine speed. The water pump is driven by an idler

gear. The idler gear is turned by the crankshaft gear.

The water pump shaft is supported by two ball

bearings. One ball bearing is located in the water

pump housing. The other ball bearing is located in the

front timing gear housing. The water pump impeller

face is open. The impeller is made out of cast iron.

The rear cover is an aluminum die casting. The water

pump seal is a cartridge seal that is located on the

inlet side of the water pump in order to provide good

water flow around the seal for cooling.

Illustration 21

g01451074

Section view of the temperature regulator housing

(9) Temperatureregulator housing

(10) Coolant temperature sensor

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22

UENR0632

Systems Operation Section

The coolant temperature regulator is a full flow

bypass type that is used to control the outlet

temperature of the coolant. When the engine is cold,

the coolant temperature regulator is in the closed

position. This allows the coolant to flow through the

coolant temperature regulator from the return

manifold. This allows the coolant to bypass the

radiator. The coolant goes directly to the water pump

for recirculation. As the coolant temperature

increases, the coolant temperature regulator begins

to open directing some of the coolant to the radiator

and bypassing the remainder to the water pump inlet.

At the full operating temperature of the engine, the

coolant temperature regulator moves to the open

position. This allows all the coolant flow to be directed

to the radiator. The coolant then goes to the water

pump. This route provides the maximum heat release

from the coolant. A vent line is recommended from

the manifold to the radiator overflow tank in order to

provide venting for the cooling system.

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UENR0632

23

Systems Operation Section

Coolant Conditioner (If Equipped)

Illustration 22

g01451075

(8) Engine oil cooler

(13) Outlet hose

(16) Coolant conditioner base

(11) Engine oil cooler elbow

(12) Coolant flow to the cylinder head

(14) Coolant flow from the water pump

(15) Coolant conditioner element

(17) Inlet hose

Some conditions of operation can cause pitting on

critical engine components. This pitting is caused by

corrosion or by cavitation erosion. The addition of a

corrosion inhibitor can keep this type of damage to a

minimum.

The precharge coolant conditioner element has more

than the normal amount of corrosion inhibitor. The

precharge coolant conditioner element is used when

a system is first filled with new coolant. This element

must add enough corrosion inhibitor in order to bring

the complete cooling system up to the correct

concentration.

Coolant conditioner element (15) is a spin-on element

that is similar to the fuel filter and to the engine oil

filter elements. The coolant conditioner element

attaches to coolant conditioner base (16) that is

mounted on the engine. Coolant flows from the water

pump through inlet hose (17) and into the coolant

conditioner base. The coolant that is conditioned then

flows through outlet hose (13) into engine oil cooler

elbow (11). There is a constant flow through the

coolant conditioner element.

The maintenance elements have a normal amount of

inhibitor and the maintenance elements are installed

at each change interval. The maintenance elements

provide enough inhibitor in order to keep the

corrosion protection at an acceptable level. In order to

provide the cooling system with protection,

maintenance elements are installed at specific

intervals.

The element has a specific amount of inhibitor for

acceptable cooling system protection. As the coolant

flows through the element, the corrosion inhibitor,

which is a dry material, disperses into the coolant.

The coolant and the inhibitor are mixed to the correct

concentration. Two basic types of elements are used

for the cooling system, the precharge and the

maintenance elements. Each type of element has a

specific use. Each type of element must be used

correctly to get the necessary concentration for

cooling system protection. The elements also contain

a filter. Even after the conditioner material is

dispersed, the elements should be left in the system

so the coolant flows through the filter.

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24

UENR0632

Systems Operation Section

Coolant for Air Compressor

•   Camshaft bearings

•   Valve mechanism

The manifold on the right supplies oil to the manifold

on the left. The oil travels through the cut above the

number one main bearing and the cut above the

number four main bearing.

Illustration 24

g00762739

Illustration 23

g01451179

Cylinder liners (1) are seated on a ridge (4) in the

middle of the cylinder wall between the crankcase

and the coolant jacket. The ridge is created by a

counterbore in the cylinder block. The cylinder liners

have a lip (2) which rests on the ridge. The seals of

the coolant jacket are located in the upper regions

and middle regions of the cylinder liners. The lower

barrier uses a D-ring seal (3) that is located above the

seating surface of the cylinder liner. The upper barrier

is the head gasket which is above the coolant jacket.

(13) Outlet hose

(17) Inlet hose

(18) Air compressor

The coolant that is used for air compressor (3) comes

from the cylinder head through inlet hose (2). The

coolant exits the air compressor through outlet hose

(1) and flows back to the cylinder head.

i02773143

The cylinder block has seven main bearings in order

to support the crankshaft. Each main bearing cap is

fastened to the cylinder block with two bolts.

Basic Engine

Pistons, Rings, and Connecting

Rods

Cylinder Block

The cylinder block is a unique design with a deep

counterbore that supports the cylinder liner. The

cylinder block also forms the coolant jacket. Two oil

manifolds are provided in the cylinder block for

engine lubrication. The manifold on the lower right

side of the cylinder block provides oil to the following

components:

The high compression ratio of the engine requires the

use of steel one piece pistons.

The pistons have three rings:

•   Compression ring

•   Intermediate ring

•   Oil ring

•   Piston cooling jets

•   Crankshaft bearings

•   Oil filter base

The manifold on the upper left side of the cylinder

block provides oil to the following components:

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UENR0632

25

Systems Operation Section

The rings are located in grooves in the piston. The

rings seal the crankcase from the combustion gases

and the rings also provide control of the engine oil.

The design of the compression ring is a barrel face

with a plasma face coating. The design of the

intermediate ring is a tapered shape and a chrome

finish. The oil ring is double railed with a coil spring

expander. The oil ring has a ground profile and a

chrome finish.

Camshaft

The connecting rod is a conventional design. The cap

is fastened to the shank by two bolts that are

threaded into the shank. Each side of the small end of

the connecting rod is machined at an angle of 12

degrees in order to fit within the piston cavity. This

allows a larger surface area on the piston, and

connecting rod in order to minimize bearing load.

Crankshaft

Illustration 25

g00762808

The crankshaft converts the linear motion of the

pistons into rotational motion. The crankshaft drives a

group of gears (front gear train) on the front of the

engine. The front gear train provides power for the

following components:

The camshaft has three lobes at each cylinder in

order to operate the unit injector, the exhaust valves,

and the inlet valves. Seven bearings support the

camshaft. The camshaft is driven by an idler gear that

is turned by the crankshaft in the front gear train.

Each bearing journal is lubricated from the oil

manifold in the cylinder block. A thrust pin that is

located at the rear of the block positions the camshaft

through a circumferential groove. The groove is

machined at the rear of the camshaft. Timing of the

camshaft is accomplished by aligning marks on the

crankshaft gear, idler gear, and camshaft gear with

each other.

•   Camshaft

•   Water pump

•   Engine oil pump

•   Air compressor

•   Fuel transfer pump

•   Accessory drive

The injector lobe on the camshaft has a modified

profile. The modified profile produces multiple

injections.

The crankshaft is held in place by seven main

bearings. The oil holes and the oil grooves in the shell

of the upper bearing supply oil to the connecting rod

bearings. The oil holes for the connecting rod

bearings are located at the following main bearing

journals: 2, 3, 5 and 6.

Vibration Damper

The force from combustion in the cylinders and from

driveline components will cause the crankshaft to

twist. This is called torsional vibration. If the vibration

is too great, the crankshaft will be damaged. Driveline

components can excite torsional stress. This stress

will cause damage to components. The vibration

damper limits the torsional vibrations to an acceptable

amount in order to prevent damage to the crankshaft.

Hydrodynamic seals are used at both ends of the

crankshaft to control oil leakage. The hydrodynamic

grooves in the seal lip move lubrication oil back into

the crankcase as the crankshaft turns. The front seal

is located in the front housing. The rear seal is

installed in the flywheel housing.

The viscous vibration damper is installed on the front

of the crankshaft. The viscous vibration damper has a

weight in a case. The space between the weight and

the case is filled with a viscous fluid. The weight

moves in the case in order to limit the torsional

vibration.

i06137706

Electrical System  

Engine Electrical System

The electrical system has the following separate

circuits:

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26

UENR0632

Systems Operation Section

•   Charging

The voltage regulator is a solid-state electronic

switch. The voltage regulator senses the voltage in

the system. The voltage regulator switches ON and

OFF many times per second in order to control the

field current for the alternator. The alternator uses the

field current in order to generate the required voltage

output.

•   Starting (If equipped)

•   Accessories with low amperage

The charging circuit is in operation when the engine is

running. An alternator makes electricity for the

charging circuit. A voltage regulator in the circuit

controls the electrical output in order to keep the

battery at full charge.

NOTICE

Never operate the alternator without the battery in the

circuit. Making  or breaking  an alternator connection

with heavy load  on the circuit can  cause damage to

the regulator.

The starting circuit is activated only when the start

switch is activated.

Charging System Components

Alternator

The alternator is driven by a belt from the crankshaft

pulley. This alternator is a three-phase, self-rectifying

charging unit, and the regulator is part of the

alternator.

The alternator design has no need for slip rings and

the only part that has movement is the rotor

assembly. All conductors that carry current are

stationary. The following conductors are in the circuit:

•   Field winding

•   Stator windings

Illustration 26

g00425518

Typical alternator components

•   Six rectifying diodes

•   Regulator circuit components

(1) Regulator

(2) Roller bearing

(3) Stator winding

(4) Ball bearing

(5) Rectifier bridge

(6) Field winding

(7) Rotor assembly

(8) Fan

The rotor assembly has many magnetic poles that

look like fingers with air space between each of the

opposite poles. The poles have residual magnetism.

The residual magnetism produces a small magnetic

field between the poles. As the rotor assembly begins

to turn between the field winding and the stator

windings, a small amount of alternating current (AC)

is produced. The AC current is produced in the stator

windings from the small magnetic field. The AC

current is changed to direct current (DC) when the AC

current passes through the diodes of the rectifier

bridge. The current is used for the following

applications:

Starting System Components

Starting Solenoid

•   Charging the battery

•   Supplying the accessory circuit that has the low

amperage

•   Strengthening the magnetic field

The first two applications use the majority of the

current. As the DC current increases through the field

windings, the strength of the magnetic field is

increased. As the magnetic field becomes stronger,

more AC current is produced in the stator windings.

The increased speed of the rotor assembly also

increases the current and voltage output of the

alternator.

Illustration 27

g00317613

Typical starting solenoid

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UENR0632

27

Systems Operation Section

When two sets of solenoid windings are used, the

windings are called the hold-in winding and the pull-in

winding. Both sets of windings have the same

number of turns around the cylinder, but the pull-in

winding uses a wire with a larger diameter. The wire

with a larger diameter produces a greater magnetic

field (1). When the start switch is closed, part of the

current flows from the battery through the hold-in

windings. The rest of the current flows through the

pull-in windings to the motor terminal. The current

then flows through the motor to ground. Solenoid (2)

is fully activated when the connection across the

battery and the motor terminal is complete. When

solenoid (2) is fully activated, the current is shut off

through the pull-in windings. At this point, only the

smaller hold-in windings are in operation. The hold-in

windings operate for the duration of time that is

required in order to start the engine. Solenoid (2) will

now draw less current from the battery, and the heat

that is generated by solenoid (2) will be kept at an

acceptable level.

Illustration 28

g00425521

Typical starting motor components

(1) Field

(2) Solenoid

(3) Clutch

(4) Pinion

(5) Commutator

(6) Brush assembly

(7) Armature

The starting solenoid (2) is an electromagnetic switch

that performs the following basic operations:

•   The starting solenoid (2) closes the high current

starting motor circuit with a low current start switch

circuit.

•   The starting solenoid (2) engages the pinion of the

starting motor (4) with the ring gear.

Solenoid (2) has windings (one or two sets) around a

hollow cylinder. A plunger that is spring loaded is

inside the cylinder. The plunger can move forward

and backward. When the start switch is closed and

electricity is sent through the windings, a magnetic

field (1) is made. The magnetic field (1) pulls the

plunger forward in the cylinder. This moves the shift

lever in order to engage the pinion drive gear with the

ring gear. The front end of the plunger then makes

contact across the battery and motor terminals of

solenoid (2). Next, the starting motor begins to turn

the flywheel of the engine.

When the start switch is opened, current no longer

flows through the windings. The spring now pushes

the plunger back to the original position. At the same

time, the spring moves the pinion gear away from the

flywheel.

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28

UENR0632

Fuel System

Testing And Adjusting

Section

2. Install a suitable fuel flow tube with a visual sight

gauge in the fuel return line. When possible, install

the sight gauge in a straight section of the fuel line

that is at least 304.8 mm (12 inches) long. Do not

install the sight gauge near the following devices

that create turbulence:

Fuel System

•   Elbows

•   Relief valves

•   Check valves

i02773147

Fuel System - Inspect

Observe the fuel flow during engine cranking. Look

for air bubbles in the fuel. If there is no fuel in the

sight gauge, prime the fuel system. Refer to

System Operation, Testing and Adjusting, “Fuel

System - Prime” for more information. If the engine

starts, check for air in the fuel at varying engine

speeds. When possible, operate the engine under

the conditions which have been suspect of air in

the fuel.

A problem with the components that send fuel to the

engine can cause low fuel pressure. This can

decrease engine performance.

1. Check the fuel level in the fuel tank. Ensure that

the vent in the fuel cap is not filled with dirt.

2. Check all fuel lines for fuel leakage. The fuel lines

must be free from restrictions and faulty bends.

Verify that the fuel return line is not collapsed.

3. Install a new fuel filter.

4. Cut the old filter open with a suitable filter cutter.

Inspect the filter for excess contamination.

Determine the source of the contamination. Make

the necessary repairs.

5. Service the primary fuel filter (if equipped).

6. Operate the hand priming pump (if equipped). If

excessive resistance is felt, inspect the fuel

pressure regulating valve. If uneven resistance is

felt, test for air in the fuel. Refer to Systems

Operation, Testing and Adjusting, “Air in Fuel -

Test” for more information.

7. Remove any air that may be in the fuel system.

Refer to Systems Operation, Testing and

Adjusting, “Fuel System - Prime”.

Illustration 29

g01096678

(1) A steady stream of small bubbles with a diameter of

approximately 1.60 mm (0.063 inch) is an acceptable amount

of air in the fuel.

(2) Bubbles with a diameter of approximately 6.35 mm  (0.250 inch)

are also acceptable if there is two seconds to three seconds

intervals between bubbles.

i02773148

Air in Fuel - Test  

(3) Excessive air bubbles in the fuel are not acceptable.

3. If excessive air is seen in the sight gauge in the fuel

return line, install a second sight gauge at the inlet

to the fuel transfer pump. If a second sight gauge

is not available, move the sight gauge from the fuel

return line and install the sight gauge at the inlet to

the fuel transfer pump. Observe the fuel flow

during engine cranking. Look for air bubbles in the

fuel. If the engine starts, check for air in the fuel at

varying engine speeds.

This procedure checks for air in the fuel. This

procedure also assists in finding the source of the air.

1. Examine the fuel system for leaks. Ensure that the

fuel line fittings are properly tightened. Check the

fuel level in the fuel tank. Air can enter the fuel

system on the suction side between the fuel

transfer pump and the fuel tank.

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UENR0632

29

Fuel System

If excessive air is not seen at the inlet to the fuel

transfer pump, the air is entering the system after

the fuel transfer pump. Proceed to Step 6.

i06196492

Electronic Unit Injector - Adjust  

If excessive air is seen at the inlet to the fuel

transfer pump, air is entering through the suction

side of the fuel system.

To  avoid personal  injury,  always  wear  eye and

face protection when using pressurized air.

4. Pressurize the fuel tank to the recommendations of

the OEM in order to avoid damage to the fuel tank.

Check for leaks in the fuel lines between the fuel

tank and the fuel transfer pump. Repair any leaks

that are found. Check the fuel pressure in order to

ensure that the fuel transfer pump is operating

properly. For information about checking the fuel

pressure, see System Operation, Testing and

Adjusting, “Fuel System Pressure - Test”.

5. If the source of the air is not found, disconnect the

supply line from the fuel tank and connect an

external fuel supply to the inlet of the fuel transfer

pump. If this corrects the problem, repair the fuel

tank or the stand pipe in the fuel tank.

Illustration 30

g01126970

Injector Mechanism

(1) Rocker arm

(2) Adjustment screw

(3) Locknut

6. If the injector sleeve is worn or damaged,

combustion gases may be leaking into the fuel

system. Also, if the O-rings on the injector sleeves

are worn, missing, or damaged, combustion gases

may leak into the fuel system.

Follow the procedure in order to adjust the electronic

unit injectors:

1. Put the No. 1 piston at the top center position on

the compression stroke. Refer to Systems

Operation, Testing and Adjusting, “Finding Top

Center Position for No. 1 Piston”.

a.

Cylinders 3, 5, and 6 can be adjusted with

cylinder 1 at Top Center compression stroke.

b.

c.

Loosen the locknut.

Turn the adjustment screw until the screw

contacts the electronic unit injector.

d.

e.

f.

Tighten the adjustment screw to an additional

two turns.

Turn the adjustment screw counterclockwise

for 2.5 turns.

Turn the adjustment screw until the screw

contacts the electronic unit injector.

g.

h.

Turn the adjustment screw through 180

degrees in a clockwise direction.

Tighten the locknut to a torque of 55 N·m

(41 lb ft).

This document has been printed from SPI2. NOT FOR RESALE