Systems Operation Testing and Adjusting

108 Pages·2013·7.63 MB·English

RENR1271-11
February 2006
Systems Operation
Testing and Adjusting
3126B and 3126E Truck Engine
BKD1-Up (Engine)
G3E1-Up (Engine)
DPF1-Up (Engine)
1AJ1-Up (Engine)
8YL1-Up (Engine)
CKM1-Up (Engine)
CRP1-Up (Engine)
7AS1-Up (Engine)
8SZ1-Up (Engine)
9SZ1-Up (Engine)
i01658146
Important Safety Information
Mostaccidentsthatinvolveproductoperation,maintenanceandrepairarecausedbyfailuretoobserve
basicsafetyrulesorprecautions.Anaccidentcanoftenbeavoidedbyrecognizingpotentiallyhazardous
situationsbeforeanaccidentoccurs.Apersonmustbealerttopotentialhazards.Thispersonshouldalso
havethenecessary training,skillsandtoolstoperformthesefunctionsproperly.
Improper operation,lubrication, maintenance or repair of this product can be dangerous and
could result in injury or death.
Donotoperateorperformanylubrication,maintenanceorrepaironthisproduct,untilyouhave
readandunderstoodtheoperation,lubrication,maintenanceandrepairinformation.
Safetyprecautionsandwarningsareprovidedinthismanualandontheproduct.Ifthesehazardwarnings
arenotheeded,bodilyinjuryor deathcouldoccurtoyouor tootherpersons.
The hazards are identified by the “Safety Alert Symbol” and followed by a “Signal Word” such as
“DANGER”,“WARNING”or“CAUTION”.TheSafetyAlert“WARNING”labelisshownbelow.
The meaning of this safety alert symbol is as follows:
Attention! Become Alert! Your Safety is Involved.
Themessagethatappearsunderthewarningexplainsthehazardandcanbeeitherwrittenorpictorially
presented.
Operations that may cause product damage are identified by “NOTICE” labels on theproduct and in
this publication.
Caterpillarcannot anticipateeverypossiblecircumstancethat mightinvolveapotentialhazard.
The warnings in this publication and on the product are, therefore, not all inclusive. If a tool,
procedure,workmethodoroperatingtechniquethatisnotspecificallyrecommendedbyCaterpillar
isused,youmustsatisfyyourselfthatitissafeforyouandforothers.Youshouldalsoensurethat
theproductwillnotbedamagedorbemadeunsafebytheoperation,lubrication,maintenanceor
repair procedures that you choose.
The information,specifications, and illustrations in this publicationare onthebasis of informationthat
was available at the time that the publication was written. The specifications, torques, pressures,
measurements,adjustments,illustrations,andotheritemscanchangeatanytime.Thesechangescan
affecttheservicethatisgiventotheproduct.Obtainthecompleteandmostcurrentinformationbeforeyou
startany job.Caterpillar dealers havethemostcurrentinformationavailable.
When replacement parts are required for this
product Caterpillar recommends using Caterpil-
lar replacement parts or parts with equivalent
specificationsincluding,butnotlimitedto,phys-
icaldimensions,type,strengthandmaterial.
Failure to heed this warning can lead to prema-
turefailures,productdamage,personalinjuryor
death.
RENR1271-11 3
Table of Contents
Table of Contents
ChargingSystem-Test ........................................ 98
ElectricStartingSystem-Test.............................. 99
EngineOilPressureSensor-Test...................... 100
Exhaust Particulate Filter Diagnostic Module -
Systems Operation Section
Test ................................................................... 100
PinionClearance-Adjust ................................... 102
GeneralInformation ................................................ 4
PinionClearance-Adjust ................................... 102
FuelSystem ........................................................... 7
AirInletandExhaustSystem ............................... 36
Index Section
LubricationSystem .............................................. 40
CoolingSystem .................................................... 42
Index ................................................................... 104
BasicEngine......................................................... 45
ElectricalSystem ................................................. 48
Testing and Adjusting Section
Fuel System
FuelSystem-Inspect ........................................... 52
AirinFuel-Test.................................................... 53
EngineSpeed-Check.......................................... 54
FindingTopCenterPositionforNo.1Piston........ 55
FuelQuality-Test................................................. 56
FuelSystem-Prime ............................................. 57
FuelSystemPressure-Test................................. 58
GearGroup(Front)-Time .................................... 60
UnitInjector-Test................................................. 60
Air Inlet and Exhaust System
AirInletandExhaustSystem-Inspect................. 62
Turbocharger-Inspect.......................................... 65
InletManifoldPressure-Test ............................... 68
ExhaustTemperature-Test.................................. 69
Aftercooler-Test................................................... 69
EngineCrankcasePressure(Blowby)-Test ........ 72
Compression-Test............................................... 73
EngineValveLash-Inspect/Adjust ...................... 73
Lubrication System
EngineOilPressure-Test .................................... 76
EngineOilPump-Inspect .................................... 79
ExcessiveBearingWear-Inspect ........................ 79
ExcessiveEngineOilConsumption-Inspect ....... 79
IncreasedEngineOilTemperature-Inspect ........ 80
Cooling System
CoolingSystem-Check(Overheating) ................ 81
CoolingSystem-Inspect...................................... 83
CoolingSystem-Test........................................... 84
WaterTemperatureRegulator-Test..................... 88
WaterPump-Test ................................................ 89
Basic Engine
PistonRingGroove-Inspect................................ 90
ConnectingRodBearings-Inspect ...................... 90
MainBearings-Inspect ........................................ 90
CylinderBlock-Inspect ........................................ 90
Flywheel-Inspect................................................. 91
FlywheelHousing-Inspect................................... 92
VibrationDamper-Check .................................... 94
VibrationDamper-Check .................................... 95
Electrical System
Battery-Test......................................................... 97
4 RENR1271-11
Systems Operation Section
Systems Operation Section
i02497376
General Information
SMCS Code: 1000
g00608514
Illustration1
Rightsideview
(1)Liftingeye (6)Belttensioner
(2)Enginecrankcasebreather (7)Waterdrainplug
(3)Turbocharger (8)Crankshaftvibrationdamper
(4)Oilfiller (9)Oilfilter
(5)Watertemperatureregulatorhousing (10)Jacketwaterpump
RENR1271-11 5
Systems Operation Section
g00608515
Illustration2
Leftsideview
(11)Oilfiller (14)Fuelprimingpump(ifequipped) (17)Aircompressor
(12)Liftingeye (15)Oillevelgauge(typicalexample) (18)Cylinderheadgroundingstud
(13)Fuelfilter (16)EngineControlModule(ECM) (19)Oildrainplug
The3126Band3126Eenginesarein-linesixcylinder Theenginehasbuilt-indiagnosticsinordertoensure
arrangements. The firing order of the engine is thatallofthecomponentsareoperatingproperly.In
1-5-3-6-2-4.Theengine’srotationiscounterclockwise theeventofasystemcomponentfailure,theoperator
whentheengineisviewedfromtheflywheelendof willbealertedtotheconditionviathecheck engine
theengine.The engineutilizes aturbocharger and lightthatislocatedonthedashboard.Anelectronic
anair-to-airaftercooler.Theengineshaveaboreof servicetoolcanbeusedtoreadthenumericalcode
110mm(4.3inch)andastrokeof127mm(5.0inch). ofthefaultycomponentorcondition.Also,thecruise
Thedisplacementis 7.25L(442cuin). controlswitchescanbeusedtoflashthecodeonthe
checkenginelight.Intermittentfaultsareloggedand
Thehydraulicelectronicunitinjectorsystem(HEUI) stored in memory.
eliminates many of the mechanical components
thatareusedinapump-and-linesystem.TheHEUI Starting The Engine
also provides increased control of the timing and
increased control ofthe fuel airmixture. Thetiming
The engine’s ECM will automatically provide the
advance is achieved by precise control of the unit
correct amount of fuel in order to start the engine.
injectortiming.Enginerpmiscontrolledbyadjusting
Do not hold the throttle down while the engine is
theinjectionduration.Aspecialpulsewheelprovides
cranking.Iftheenginefailstostartintwentyseconds,
informationtotheEngineControlModule(ECM)for
releasethestartingswitch.Allow thestartingmotor
detectionofcylinderpositionandenginerpm.
to cool for twominutes before the starting motor is
used again.
6 RENR1271-11
Systems Operation Section
NOTICE
Excessive ether (starting fluid) can cause piston and
ringdamage.Useetherforcoldweatherstartingpur-
poses only.
Cold Mode Operation
Starting the engine and operation in cold weather
isdependentonthetypeoffuelthatisused,theoil
viscosity,andother optionalstartingaids.For more
information,refertotheOperationandMaintenance
Manual,“ColdWeatherOperation” topic(Operation
Section).
i01750138
Fuel System
SMCS Code: 1250
RENR1271-11 7
Systems Operation Section
Introduction
g00457847
Illustration3
DiagramofcomponentsfortheHEUIfuelsystem
8 RENR1271-11
Systems Operation Section
(1)Unitinjectorhydraulicpump (14)Speed/timingsensors (27)Inletairheaterlamp
(2)Oilflowtoengine (15)ECM (28)Fastidlelamp
(3)Oilfilter (16)Boostpressuresensor (29)Checkenginelamp
(4)Engineoilpump (17)Acceleratorpedal (30)Speedometerandtachometer
(5)Oilcooler (18)Acceleratorpedalpositionsensor (31)CruiseON/OFFswitchandCruise
(6)IAPsensor (19)Batteries SET/RESUMEswitch
(7)Injectors (20)Coolanttemperaturesensor (32)PTOON/OFFswitchandSET/RESUME
(8)Fuelsupplyrail (21)Datalink switch
(9)Fuelpressureregulator (22)Exhaustbrakerelay (33)Servicebrakeswitches
(10)IAPcontrolvalve (23)Inletairtemperaturesensor (34)Neutralandclutchswitches
(11)Fuelfilter (24)Transmissionrelay (35)Fueltransferpump
(12)Fueltank (25)Vehiclespeedsensor
(13)Backofcamgear (26)Inletairheaterrelay
The operation of the Hydraulic Electronic Unit The HEUI uses engine lubrication oil that is
Injector (HEUI) fuel system is completely different pressurized from 6 MPa (870 psi) to 27.5 MPa
fromany other typeoffuel system that is actuated (4000 psi) in order to pump fuel from the injector.
mechanically. The HEUI fuel system is completely TheHEUIoperatesinthesameway asahydraulic
freeofadjustment.Adjustments tothecomponents cylinder in order to multiply the force of the high
that are mechanical can not be made.Changes in pressure oil. By multiplying the force of the high
performancearemadebyinstallingdifferentsoftware pressure oil, the HEUI can produce injection
inEngineControlModule(ECM)(15). pressures that are very high. This multiplication of
pressureisachievedbyapplyingtheforceofthehigh
Thisfuelsystemconsistsofsixbasiccomponents: pressureoiltoapiston.Thepistonislargerthanthe
plungerbyapproximatelysixtimes.Thepistonthatis
• HydraulicElectronicUnitInjector(HEUI)(7) poweredbyenginelubricationoilunderhighpressure
pushes on the plunger. This engine lubrication oil
• EngineControlModule(ECM) (15) underhighpressureiscalledtheactuationpressure
oftheoil.Theactuationpressureoftheoilgenerates
• Unitinjector hydraulic pump (1) the injection pressure that is delivered by the unit
injector.Injectionpressureisgreaterthanactuation
• InjectionActuationPressureControlValve(10) pressureoftheoilbyapproximatelysixtimes.
• Fuel Transfer Pump (35) Low actuation pressure of the oil results in low
injectionpressureofthefuel.Duringconditionsoflow
• InjectionActuationPressureSensor(6) speedsuchasidleandstart,lowinjectionpressureis
utilized.
Note: The components of the HEUI fuel system
arenotserviceable.Thesefuelsystemcomponents High actuation pressure of the oil results in high
mustnotbedisassembled.Disassemblywilldamage injection pressure of the fuel. During conditions of
the components. If the components have been highspeedsuchashighidleandacceleration,high
disassembled,Caterpillarmaynotallow awarranty injection pressure is utilized.
claimorCaterpillarmayreducethewarrantyclaim.
Therearemanyotheroperatingconditionswhenthe
Component Description injectionpressureisbetweentheminimum andthe
maximum. Regardless of the speed of the engine,
the HEUI fuel system provides infinite control of
Hydraulic Electronic Unit Injector
injection pressure.
TheHEUIfuelsystemutilizesahydraulicallyactuated
Engine Control Module (ECM)
electronicallycontrolledunitinjector(7).
Engine Control Module (ECM) (15) is located on
All fuel systems for diesel engines use a plunger
the left side of the engine. The ECM is a powerful
andbarrelinordertopumpfuelunderhighpressure
computer that provides total electronic control of
into the combustion chamber. This fuel is pumped
engine performance. The ECM uses data from
intothecombustionchamber inpreciseamountsin
engine performance that is gathered by several
ordertocontrolengineperformance.TheHEUIuses
sensors. Then, the ECM uses this data in order
engineoilunderhighpressureinordertopowerthe
to make adjustments to the fuel delivery, injection
plunger. All other fuel systems use a fuel injection
pressure and injection timing. The ECM contains
pump camshaftlobe in order topower theplunger.
programmedperformancemaps(software)inorder
Because the HEUI is much different, a technician
to define horsepower,torquecurves andrpm.This
mustusedifferenttroubleshootingmethods.
softwareiscommonlycalledthepersonalitymodule.
RENR1271-11 9
Systems Operation Section
Some engines use Engine Control Modules Fuel transfer pump (35) is a single piston pump
(ECM) (15) with a replaceable computer chip. that is spring loaded. The shaft of the unit injector
The software has already been installed in the hydraulicpumpprovidespowertothetransferpump
replaceablecomputer chip.The 3126B and3126E throughanoff-centerbearing.There aretwocheck
diesel truck engines do not have a replaceable valves in the fuel transfer pump. The inlet check
personality module. The 3126B and 3126E diesel valveopens inordertoallow fuelfromthetank into
truck engine’s personality modulearea permanent the pump. The inlet check valve closes in order
partoftheECM.The3126Band3126Edieseltruck to prevent fuel leakage back to the fuel tank. The
engine’spersonalitymodulecanbereprogrammed. outlet check valve opens in order to supply fuel to
Reprogramming ofthepersonality module requires thefuelsupplypassage.Thefuelsupplypassageis
theuseofCaterpillarElectronicTechnician(CatET). locatedinthecylinderhead.Thefuelsupplypassage
TheflashfunctionofCatET willbeusedduringthe suppliesfueltoinjectors (7).Theoutletcheckvalve
reprogramming. closes inorder topreventpressurizedfuelleakage
back through the pump.
ECM (15) logs faults of engine performance. Also,
the ECM is capable of running several diagnostic Injection Actuation Pressure Sensor
tests automatically when the ECM is used with an
(IAP)
electronicservicetoolsuchastheCatET.
IAP Sensor (6) is installed in the high pressure oil
Unit injector hydraulic pump
manifold. The high pressure oil manifold supplies
actuationoilinordertopowertheunitinjectors.The
Unit injector hydraulic pump (1) (high pressure oil IAP Sensor monitors injection actuation pressure.
pump)islocatedattheleftfrontcorneroftheengine. The IAP Sensor sendsa continuous voltage signal
Theunitinjectorhydraulicpumpisapistonpumpthat back to ECM (15). The ECM interprets the signal.
hasafixeddisplacement.Theunitinjectorhydraulic TheECMisawareoftheinjectionactuationpressure
pumpusesanaxialpiston.Theunitinjectorhydraulic at all times.
pumpusesaportionoftheenginelubricationoil.The
unitinjector hydraulicpump pressurizestheengine
lubricationoiltotheinjectionactuationpressurethat
isrequiredinordertopowertheHEUIinjectors.
Injection Actuation Pressure Control
Valve (IAP Control Valve)
Injection actuationpressurecontrolvalve(10) (IAP
Control Valve) is locatedonthe sideofunitinjector
hydraulic pump (1). Under most conditions, the
pump is producingexcessoil flow.The IAP Control
Valve discharges excess pump flow to the drain in
order to control injection actuation pressure to the
desiredlevel.TheIAPControlValveisavalveofhigh
precisionthatcontrolstheactualactuationpressure.
The performance maps of ECM (15) contain a
desiredactuationpressureforeveryengineoperating
condition. The ECM sends a control current to the
IAPControlValve.Thecontrolcurrentshouldmake
the actual actuation pressure equal to the desired
actuation pressure.
IAPControlValve(10)isanactuator.TheIAPControl
ValveconvertsanelectricalsignalfromECM(15)to
the mechanical control of aspool valve in order to
control pump outlet pressure.
Fuel Transfer Pump
Fuel transfer pump(35) is mounted on the back of
unit injector hydraulic pump (1). The fuel transfer
pump is used in order to draw fuel from fuel tank
(12). Also, the fuel transfer pump is used in order
to pressurize the fuel to 450 kPa (65 psi). The
pressurizedfuelissuppliedtoinjectors(7).
10 RENR1271-11
Systems Operation Section
HEUI Fuel System Operation
Low Pressure Fuel System
g00458217
Illustration4
Lowpressurefuelsystem