BASIC DIESEL ENGINE TECHNOLOGY

TRI-CO. YOUNG FARMERS

DECEMBER 4, 2001

Original Power Point created By Joey Wells

Modified by Georgia Agricultural Education

Curriculum Office

June 2002

INTRODUCTION

• THE DIESEL ENGINE IS USED AS A SOURCE OF POWER FOR THOUSANDS OF APPLICATIONS.

WHO INVENTED THE DIESEL ENGINE?

• 1895 – RUDOLPH DIESEL SUCCESSFULLY INVENTED AN ENGINE THAT BURNED COAL DUST INJECTED BY PRESSURIZED AIR. THE DIESEL ENGINE WAS BORN.

WHO DEVELOPED THE FIRST MASS PRODUCED

INJECTION PUMP?

• ROBERT BOSCH IN 1927

USES OF DIESEL ENGINES

TODAY, DIESEL ENGINES ARE USED TO PROVIDE POWER IN A VARIETY OF APPLICATIONS IN

MANY INDUSTRIES

THERE ARE SIX MAJOR USES OF DIESEL ENGINES

AGRICULTURE/FARM

TRANSPORTATION

CONSTRUCTION

FORESTRY

MARINE

ELECTRICAL GENERATION PLANTS

SEVEN ADVANTAGES OF DIESEL ENGINES

• MORE EFFICIENT AND ECONOMICAL TO USE

• FUEL VAPOR IS NOT EXPLOSIVE• EXHAUST GASES ARE LESS

POISONOUS – LESS CARBON MONOXIDE

• GREATER LUGGING POWER AND TORQUE

ADVANTAGES CONTINUED

• ENGINES ARE DURABLE AND IF PROPERLY CARED FOR WILL MAINTAIN THEIR ECONOMY

• FUEL IS LESS VOLATILE – NO VAPOR LOCK PROBLEMS

• CAN USE A VARIETY OF FUELS AND MIXTURES

FIVE DISADVANTAGES OF DIESEL ENGINES

• ENGINES MUST BE STONGER AND HEAVIER BECAUSE OF HIGHER COMPRESSION RATES

• INITIALLY MORE EXPENSIVE• FUEL COULD GEL IN COLDER

CLIMATES• GENERALLY NOISER OPERATION• VERY PUNGENT EXHAUST ODOR

INTERNAL COMBUSTION ENGINE:

AN ENGINE THAT PRODUCES POWER BY BURNING FUEL INSIDE A COMBUSTION CHAMBER WITHIN THE ENGINE

TWO TYPES OF INTERNAL COMBUSTION ENGINES

SPARK IGNITION ENGINE

COMPRESSION IGNITION ENGINE

TRUE OR FALSE: SPARK PLUGS SHOULD BE CHANGED MORE OFTEN IN DIESEL ENGINES THAN IN GASOLINE ENGINES?

FALSE

BASICALLY, HOW DOES A SPARK-IGNITION ENGINE

WORK?

• LIQUID FUEL BROKEN DOWN INTO A FINE SPRAY AND MIXED WITH AIR IN THE CARBURETOR.

• FUEL-AIR MIXTURE PIPED TO THE CYLINDER WHERE IT IS IGNITED BY AN ELECTRIC SPARK FROM THE SPARK PLUG.

HOW DOES A COMPRESSION-IGNITION

ENGINE WORK?

• NO SPARK IS NEEDED• LIQUID FUEL UNDER VERY HIGH

PRESSURE IS INJECTED DIRECTLY INTO THE CYLINDER WHICH IS FILLED WITH HIGHLY COMPRESSED AIR.

• IGNITION BEGINS WHEN THE FUEL HITS THE AIR THAT IS AT A TEMPERATURE OF 777 DEGREES F.

WHAT DOES A COMPRESSION RATIO OF

16:1 MEAN?

THE AIR IN A CYLINDER IS COMPRESSED INTO 1/16 THE

SPACE AT THE TOP OF THE STROKE AS COMPARED TO THE

BOTTOM OF THE STROKE

TRUE OR FALSE: DIESEL ENGINES USE GREATER COMPRESSION RATIOS

THAN GASOLINE ENGINES?

TRUE

DIESEL ENGINES – 16:1 TO 22:1

GASOLINE ENGINES – 8:1

TRUE OR FALSE: DIESEL ENGINES REQUIRE MORE

AIR THAN GASOLINE ENGINES

TRUE

TRUE OR FALSE: DIESEL ENGINES HAVE NO IGNITION SYSTEM

COMPONENTS

TRUE

NO SPARK PLUGS, COIL, MAGNETO, DISTRIBUTOR, OR

WIRING

TRUE OR FALSE: DIESEL ENGINES, LIKE GASOLINE ENGINES, DRAW IN FUEL AND AIR ON THE INTAKE

STROKE?

FALSE

ONLY AIR IN A DIESEL ENGINE

WHAT IS THE PURPOSE OF A TURBOCHARGER ON A

DIESEL ENGINE?

TO INCREASE THE AIR INTAKE INTO THE CYLINDERS

TRUE OR FALSE: DIESEL ENGINES REQUIRE A HIGH

PRESSURE PUMP TO INJECT THE FUEL INTO THE

COMPRESSED AIR IN THE CYLINDER?

TRUE

WHAT IS THE NAME OF THE ENGINE PART THAT SPRAYS FUEL INTO THE CYLINDER

OF A DIESEL ENGINE?

INJECTOR NOZZEL

WHAT TYPE MATERIAL ARE FUEL LINES MADE OF IN A

DIESEL ENGINE? WHY?

STEEL

PRESSURES FROM 5,000 TO 20,000 PSI ARE INVOLVED

TRUE OR FALSE: GASOLINE IS LESS VOLATILE THAN

DIESEL FUELS

FALSE

GASOLINE EVAPORATES READILY AND IS VERY

EXPLOSIVE

TRUE OR FALSE: GASOLINE ENGINES ARE HEAVIER

THAN DIESEL ENGINES OF THE SAME HORSEPOWER?

FALSE

HIGH DIESEL CYLINDER PRESSURES REQUIRE HEAVIER

MATERIALS

HOW IS ENGINE SPEED CONTROLLED IN A DIESEL

ENGINE?

• THE THROTTLE CONTROL REGULATES ONLY THE AMOUNT OF FUEL INJECTED INTO THE CYLINDER

• THE THROTTLE CONTROL IN A GASOLINE ENGINE REGULATES THE AMOUNT OF AIR/FUEL MIXTURE ALLOWED INTO THE CYLINDER

HOW ARE DIESEL ENGINES STOPPED?

• BY SHUTTING OFF THE FUEL TO THE CYLINDERS BY A MANUAL CONTROL OR SOLENOID SWITCH

• GASOLINE ENGINES ARE STOPPED BY CUTTING OFF THE SPARK FROM THE SPARK PLUGS TO THE CYLINDERS

HOW AN ENGINE WORKS

WHAT ARE THE FIVE BASIC PARTS OF ANY ENGINE?

NAME THE TWO BASIC TYPES OF ENGINES

• FOUR STROKE CYCLE ENGINE

• TWO STROKE CYCLE ENGINE

WHAT SEQUENCE OF EVENTS MAKE UP A

CYCLE?• INTAKE

• COMPRESSION

• POWER

• EXHAUST

• WHAT IS A STROKE?

• ONE MOVEMENT OF THE PISTON

FOUR STROKES OF AN ENGINE

HOW MANY TIMES DOES THE CRANKSHAFT

REVOLVE DURING A CYCLE IN A FOUR STROKE CYCLE

ENGINE?

TWO

WHAT ARE THE MAJOR DIFFERENCES IN EACH

STROKE WHEN COMPARING A DIESEL

ENGINE WITH A GASOLINE ENGINE?

• INTAKE – AIR VS. AIR/FUEL MIXTURE

DIFFERENCES CONTINUED

• COMPRESSION STROKE– COMPRESSION RATIO

• POWER STROKE– SPARK PLUG VS. HEAT OF

COMPRESSION

• EXHAUST STROKE– SAME FOR BOTH

TWO-STROKE CYCLE ENGINES

HOW MANY STROKES OF THE PISTON ARE REQUIRED

FOR A CYCLE TO BE COMPLETED IN A TWO

STROKE CYCLE ENGINE?

TWO

WHAT HAPPENS DURING STROKE 1 IN A TWO

STROKE CYCLE GASOLINE ENGINE?

• THE UPSTROKE OF THE PISTON COMPRESSES THE AIR/FUEL MIXTURE. (COMPRESSION STROKE)

• AT THE SAME TIME, A NEW AIR-FUEL MIXTURE IS DRAWN INTO THE CRANKCASE. (INTAKE STROKE)

WHAT HAPPENS DURING STROKE 2 OF A TWO

STROKE CYCLE GASOLINE ENGINE?

• THE DOWNWARD STROKE (POWER STROKE) OF THE PISTON CAUSES THE BURNED GASES TO ESCAPE THROUGH THE EXHAUST PORT. (EXHAUST STROKE)

• NEW FUEL-AIR IS FORCED INTO THE CYLINDER

TWO-STROKE CYCLE GASOLINE ENGINES

WHAT ARE THE DIFFERENCES BETWEEN A

DIESEL AND GASOLINE TWO-STROKE CYCLE

ENGINE?• DIESEL ENGINES INJECT FUEL INTO THE

CYLINDER THROUGH A FUEL INJECTOR• A BLOWER IS OFTEN USED TO FORCE AIR INTO

THE CYLINDER• DIESEL ENGINES HAVE EXHAUST VALVES, GAS

ENGINES HAVE A PORT

TWO-STROKE DIESEL ENGINE

THE DIESEL AIR SYSTEM

BASIC PARTS OF THE DIESEL AIR SYSTEM

WHAT IS A TURBOCHARGER ON A DIESEL ENGINE?

A CENTRIFUGAL BLOWER THAT IS DRIVEN BY EXHAUST GASES WHICH FORCES MORE

AIR INTO THE CYLINDER. INCREASES POWER

HOW IMPORTANT IS KEEPING AIR FILTERS

CLEAN?

VERY IMPORTANT

A DIESEL ENGINE USES 12-15,000 GALLONS OF AIR TO

EACH GALLON OF FUEL

NAME THREE TYPES OF AIR CLEANERS

• OIL-BATH TYPE CLEANER

• PRE-CLEANER

• DRY-TYPE AIR CLEANER

THE DIESEL FUEL SYSTEM

WHAT ARE THE FIVE BASIC PARTS OF A DIESEL FUEL

SYSTEM?

• INJECTION NOZZLES

• INJECTION PUMP

• FILTERS

• TRANSFER PUMP

• FUEL TANK

THE DIESEL FUEL SYSTEM

DIESEL FUEL, LIKE GASOLINE IS A PRODUCT OF

THE DISTILLATION OF-

CRUDE OIL

100 GALLONS OF CRUDE OIL WILL YIELD WHAT

PRODUCTS?

• GASOLINE = 44 GALLONS

• DIESEL FUEL = 36 GALLONS

• MISC. = 9 GALLONS

• KEROSENE = 6 GALLONS

• LUBRICANTS = 3 GALLONS

• LOSS = 3 GALLONS

WHAT ARE THE THREE GRADES OF DIESEL FUEL?

• NUMBER 1 DIESEL FUEL (NO. 1-D)– RECOMMENDED FOR COLD WEATHER.

REMAINS FLUID FOR EASIER STARTING– BUSES, CARS, TRUCKS, FARM TRACTORS

• NUMBER 2 DIESEL FUEL (NO. 2-D)– HEAVY WORK LOADS. BUSES, TRUCKS,

FARM EQUIPMENT

• NUMBER 4 DIESEL FUEL (NO. 4-D)– OCEAN GOING VESSELS WITH LOW-MEDIUM

SPEED ENGINES

THE DIESEL COOLING SYSTEM

WHAT ARE TWO PRIMARY TYPES OF COOLING

SYSTEMS FOR DIESEL ENGINES?

LIQUID COOLING

AIR-COOLING

LIQUID COOLING ENGINE

AIR-COOLED DIESEL ENGINE

WHAT IS THE IDEAL OPERATING TEMPERATURE

FOR MOST DIESEL ENGINES?

165 – 185 DEGREES F.

WHAT ARE SOME EFFECTS OF ENGINE OVERHEATING?

• CYLINDER HEAD AND BLOCK CAN CRACK OR WARP

• RINGS AND VALVES MAY SEIZE OR STICK DUE TO GUMS, LAQUERS, AND VARNISHES FORMING FROM OVERHEATED OIL AND CARBON FORMATION

• BEARINGS MAY BE DAMAGED CAUSING EXCESSIVE WEAR

WHAT ARE SOME EFFECTS OF OVERCOOLING?

• INCREASED ENGINE WEAR

• IMPROPER LUBRICATION

• INCREASED FUEL CONSUMPTION

• INCREASED SLUDGE FORMATION

• INCREASED ENGINE CORROSION– MOISTURE CONDENSES IF BELOW 140

DEGREES IN THE ENGINE CRANKCASE

WHAT ARE SOME ADVANTAGES OF AIR-

COOLED ENGINES• LESS WEIGHT• LESS MAINTENANCE• LESS DOWN-TIME• NO CAVITATION EROSION• NO COOLANT CONCERNS• MORE EFFICIENT USE OF POWER• LESS VULNERABLE TO DAMAGE• LESS BULK• QUICKER WARM-UP

WHAT ARE SOME DISADVANTAGES TO AIR-

COOLED ENGINES?

• LENGTH OF THE ENGINE

• LESS TEMPERATURE CONTROL

• HIGHER OPERATING TEMPERATURES

• GREATER NOISE

• MORE FREQUENT CLEANING

THE DIESEL LUBRICATION SYSTEM

WHAT ARE THE FUNCTIONS FOR THE LUBRICATION

SYSTEM?

• REDUCES SHOCK, WEAR, AND FRICTION

• SEALS COMPRESSION• PROVIDES SOME CLEANING• HELPS COOL THE ENGINE• QUIETS THE ENGINE OPERATION

TRUE OR FALSE: MOST OF THE LUBRICANTS USED IN

DIESEL ENGINES COME FROM PETROLEUM?

TRUE

WHAT ARE LUBRICANTS DERIVED FROM ANIMAL OR VEGETABLE OILS CALLED?

SYNTHETIC OILS

WHAT TWO CHARACTERISTICS ARE

MOST IMPORTANT IN CHOOSING PROPER OIL?

VISCOSITY

SERVICE CLASSIFICATION

WHAT IS VISCOSITY?

• A MEASURE OF A LIQUID’S RESISTANCE TO FLOW

• HIGHER TEMPERATURE – DECREASE IN VISCOSITY

• SOCIETY OF AUTOMOTIVE ENGINEERS (SAE) DEVELOPED NUMBERING SYSTEM

WHAT ARE THE VISCOSITY GRADES?

API ENGINE OIL SERVICE CATEGORIES

AMERICAN PETROLEUM INSTITUTE

TABLE 1: (HANDOUT)

WHAT ARE THE THREE MOST COMMON OIL

ADDITIVES?• OXIDATION INHIBITORS

• CORROSION AND RUST INHIBITORS

• DETERGENT DISPERSANTS

HOW DO DETERGENT ADDITIVES WORK?

PRINCIPLES OF FLUID HYDRAULICS

HYDRAULIC SYSTEMS ON A TRACTOR

WHAT IS PASCAL’S LAW OF HYDRAULICS?

• PRESSURE ON A LIQUID IN A CONTAINER IS TRANSFERRED EQUALLY TO ALL SURFACES

PASCAL’S LAW

PRESSURE TRANSFER IN HYDRAULIC BRAKES

CHANGING THE PRESSURE IN A HYDRAULIC SYSTEM