Navistar N13 User manual

ENGINESERVICEMANUAL0000003823 Navistar®N13withSCRRevision1 EPA10-US,Canada,MexicoApril2014
ENGINESERVICEMANUAL
Navistar®N13withSCR
Navistar,Inc.
2701NavistarDrive,Lisle,IL60532USA
©2014Navistar,Inc.Allrightsreserved.Allmarksaretrademarksoftheirrespectiveowners.

SummaryofChanges
SectionUpdatedDescription
EngineSystemsInsertedupdatedEngineSystemssectiontakenfrom0000002161R9
InletAirHeaterSystem•InstallationprocedureupdatedtoreectcorrectinstallationoftheIAHFI
intheairintakethrottleduct.
EngineElectricalAddedfollowingnewsections:
•NOxINsensormodule
•AFTPAV
•AFTFI
•AFTFP1
•AFTFSV
RemoveMAFsensorprocedures.
AftertreatmentSystemNeworupdatedprocedures:
•Aftertreatment(AFT)FuelDoserModule
•AftertreatmentPurgeAirValve(AFTPAV)Assembly
•AftertreatmentFuelInjector(AFTFI)Assembly
•AFTICoolantReturnTubeAssembly
•AFTICoolantSupplyTubeAssembly
•AFTIFuelTubeAssembly
RemovePDOCsections
Changenamingof“meteringunit”to“AFTfueldosermodule”
FuelSystemNeworupdatedprocedures:
•FuelSupplyandDrain(Return)Lines
•FuelFilterHousingAssembly
AppendixDInsertedAppendixD:ComponentLocator—copiedfrom0000002161R9

ENGINESERVICEMANUALI
TABLEOFCONTENTS
Foreword...................................................................................................................1
ServiceDiagnosis........................................................................................................2
SafetyInformation........................................................................................................3
EngineSystems...........................................................................................................5
MountingEngineonStand............................................................................................53
EngineElectrical.........................................................................................................61
InletAirHeaterSystem...............................................................................................107
AftertreatmentSystem................................................................................................119
ExhaustBackPressureControl.....................................................................................143
Turbochargers..........................................................................................................157
AirCompressorandPowerSteering...............................................................................207
FuelSystem.............................................................................................................221
OilCooler,FilterHousing,andCrankcaseVentilation..........................................................277
ExhaustGasRecirculation(EGR)System.........................................................................295
AirIntakeThrottleDuctandExhaustManifold...................................................................331
FrontCover,FanDrive,CoolingSystem,andRelatedComponents.........................................353
Navistar®N13EngineBrakebyJacobs............................................................................383
CylinderHead,CamshaftandValveTrain.........................................................................399
FlywheelandFlywheelHousing.....................................................................................435
OilPanandOilPickupTube.........................................................................................453
OilPumpandTimingGears..........................................................................................469
PowerCylinders........................................................................................................485
CrankcaseandCrankshaft...........................................................................................505
AbbreviationsandAcronyms........................................................................................519
Terminology.............................................................................................................525

IIENGINESERVICEMANUAL
AppendixA–Specications.........................................................................................537
AppendixB–Torques.................................................................................................543
AppendixC–SpecialServiceTools................................................................................561
AppendixD:ComponentLocator...................................................................................577

ENGINESERVICEMANUAL1
Foreword
Navistar,Inc.iscommittedtocontinuousresearch
anddevelopmenttoimproveproductsandintroduce
technologicaladvances.Procedures,specications,
andpartsdenedinpublishedtechnicalservice
literaturemaybealtered.
ThisEngineServiceManualprovidesageneral
sequenceofproceduresforout-of-chassisengine
overhaul(removal,inspection,andinstallation).For
in-chassisserviceofpartsandassemblies,the
sequencemayvary.
NOTE:Photoillustrationsidentifyspecicparts
orassembliesthatsupporttextandprocedures;
otherareasinaphotoillustrationmaynotbe
exact.
SeevehiclemanualsandTechnicalService
Information(TSI)bulletinsforadditionalinformation.
Navistar®N13withSCREngineOperationand
MaintenanceManual
Navistar®N13withSCREngineServiceManual
(EPA10)
Navistar®N13withSCREngineDiagnosticManual
(EPA10)
Navistar®N13withSCRHardStartandNoStart
DiagnosticsForm(EPA10)
N13withSCRPerformanceDiagnosticsForm
(EPA10)
Navistar®N13withSCRElectronicControlSystem
DiagnosticsForm(EPA10)
TechnicalServiceLiteratureisrevisedperiodically.If
atechnicalpublicationisordered,thelatestrevision
willbesupplied.
NOTE:Toordertechnicalserviceliterature,
contactyourInternationaldealer.
Allmarksaretrademarksoftheirrespectiveowners.

2ENGINESERVICEMANUAL
ServiceDiagnosis
Servicediagnosisisaninvestigativeprocedurethat
mustbefollowedtondandcorrectanengine
applicationproblemoranengineproblem.
Iftheproblemisengineapplication,seespecic
vehiclemanualsforfurtherdiagnosticinformation.
Iftheproblemistheengine,seespecicEngine
DiagnosticManualforfurtherdiagnosticinformation.
PrerequisitesforEffectiveDiagnosis
•Availabilityofgauges,diagnostictestequipment,
anddiagnosticsoftware.
•Availabilityofcurrentinformationforengine
applicationandenginesystems.
•Knowledgeoftheprinciplesofoperationfor
engineapplicationandenginesystems.
•Knowledgetounderstandanddoproceduresin
diagnosticandservicepublications.
TechnicalServiceLiteraturerequiredforEffective
Diagnosis
•EngineServiceManual
•EngineDiagnosticManual
•DiagnosticsForms
•ElectronicControlSystemsDiagnosticsForms
•ServiceBulletins

ENGINESERVICEMANUAL3
SafetyInformation
Thismanualprovidesgeneralandspecic
maintenanceproceduresessentialforreliableengine
operationandyoursafety.Sincemanyvariationsin
procedures,tools,andservicepartsareinvolved,
adviceforallpossiblesafetyconditionsandhazards
cannotbestated.
Readsafetyinstructionsbeforedoinganyserviceand
testproceduresfortheengineorvehicle.Seerelated
applicationmanualsformoreinformation.
ObeySafetyInstructions,Warnings,Cautions,and
Notesinthismanual.Notfollowingwarnings,
cautions,andnotescanleadtoinjury,deathor
damagetotheengineorvehicle.
SafetyTerminology
Threetermsareusedtostressyoursafetyandsafe
operationoftheengine:Warning,Caution,andNote
Warning:Awarningdescribesactionsnecessaryto
preventoreliminateconditions,hazards,andunsafe
practicesthatcancausepersonalinjuryordeath.
Caution:Acautiondescribesactionsnecessary
topreventoreliminateconditionsthatcancause
damagetotheengineorvehicle.
Note:Anotedescribesactionsnecessaryforcorrect,
efcientengineoperation.
SafetyInstructions
WorkArea
•Keepworkareaclean,dry,andorganized.
•Keeptoolsandpartsofftheoor.
•Makesuretheworkareaisventilatedandwelllit.
•MakesureaFirstAidKitisavailable.
SafetyEquipment
•Usecorrectliftingdevices.
•Usesafetyblocksandstands.
ProtectiveMeasures
•Wearprotectivesafetyglassesandshoes.
•Wearcorrecthearingprotection.
•Wearcottonworkclothing.
•Wearsleevedheatprotectivegloves.
•Donotwearrings,watchesorotherjewelry.
•Restrainlonghair.
Vehicle
•Shifttransmissiontoparkorneutral,setparking
brake,andblockwheelsbeforedoingdiagnostic
orserviceprocedures.
•Cleartheareabeforestartingtheengine.
Engine
•Theengineshouldbeoperatedorservicedonly
byqualiedindividuals.
•Providenecessaryventilationwhenoperating
engineinaclosedarea.
•Keepcombustiblematerialawayfromengine
exhaustsystemandexhaustmanifolds.
•Installallshields,guards,andaccesscovers
beforeoperatingengine.
•Donotrunenginewithunprotectedairinletsor
exhaustopenings.Ifunavoidableforservice
reasons,putprotectivescreensoverallopenings
beforeservicingengine.
•Shutengineoffandrelieveallpressureinthe
systembeforeremovingpanels,housingcovers,
andcaps.
•Ifanengineisnotsafetooperate,tagtheengine
andignitionkey.
FirePrevention
•Makesurechargedreextinguishersareinthe
workarea.
NOTE:Checktheclassicationofeachre
extinguishertoensurethatthefollowingre
typescanbeextinguished.
1.TypeA—Wood,paper,textiles,andrubbish
2.TypeB—Flammableliquids
3.TypeC—Electricalequipment
Batteries
•Alwaysdisconnectthemainnegativebattery
cablerst.
•Alwaysconnectthemainnegativebatterycable
last.
•Avoidleaningoverbatteries.

4ENGINESERVICEMANUAL
•Protectyoureyes.
•Donotexposebatteriestoamesorsparks.
•Donotsmokeinworkplace.
CompressedAir
•UseanOSHAapprovedblowgunratedat207
kPa(30psi).
•Limitairpressureto207kPa(30psi).
•Wearsafetyglassesorgoggles.
•Wearhearingprotection.
•Useshieldingtoprotectothersintheworkarea.
•Donotdirectcompressedairatbodyorclothing.
Tools
•Makesurealltoolsareingoodcondition.
•Makesureallstandardelectricaltoolsare
grounded.
•Checkforfrayedordamagedpowercordsbefore
usingpowertools.
FluidsUnderPressure
•Useextremecautionwhenworkingonsystems
underpressure.
•Followapprovedproceduresonly.
Fuel
•Donotoverllthefueltank.Overllcreatesare
hazard.
•Donotsmokeintheworkarea.
•Donotrefuelthetankwhentheengineisrunning.
RemovalofTools,Parts,andEquipment
•Reinstallallsafetyguards,shields,andcovers
afterservicingtheengine.
•Makesurealltools,parts,andserviceequipment
areremovedfromtheengineandvehicleafterall
workisdone.

ENGINESYSTEMS5
TableofContents
EngineIdentication.....................................................................................................7
EngineSerialNumber..........................................................................................7
EngineEmissionLabel........................................................................................7
EngineAccessoryLabelsandIdenticationPlates.......................................................8
EngineSpecications..........................................................................................8
HeavyDutyOnBoardDiagnostics(HD-OBD)...................................................10
EngineDescription...................................................................................10
OptionalEquipment..................................................................................11
ChassisMountedEquipment.......................................................................11
AirManagementSystem...............................................................................................12
Airow...........................................................................................................13
Turbochargers..................................................................................................14
AirControlValve(ACV).......................................................................................15
BoostControl...................................................................................................15
LowPressureChargeAirCooler(LPCAC)................................................................16
HighPressureChargeAirCooler(HPCAC)...............................................................16
IntakeManifoldPressure(IMP)Sensor...................................................................16
IntakeManifoldTemperature(IMT)Sensor...............................................................16
Turbocharger2CompressorInletSensor(TC2IS)......................................................16
ExhaustGasRecirculation(EGR)System................................................................17
Aftertreatment(AFT)System................................................................................20
DecompositionReactorTube......................................................................21
DieselParticulateFilter(DPF)......................................................................21
DieselOxidationCatalyst(DOC)...................................................................21
SelectiveCatalystReduction(SCR)Catalyst...................................................21
Aftertreatment(AFT)SystemConditionsandResponses....................................21
DieselExhaustFluid(DEF)Injection.............................................................22
AftertreatmentFuelInjection.......................................................................23
CrankcaseOilSeparator......................................................................................25
FuelManagementSystem.............................................................................................27
FuelSystemComponents....................................................................................27
FuelFlow........................................................................................................28
LowPressureFuelSystem...................................................................................29
HighPressureFuelSystem..................................................................................31
InletAirHeaterSystem.................................................................................................32
InletAirHeaterSystemComponents......................................................................32
InletAirHeaterSystemOperation..........................................................................33
OilFlowandComponents.............................................................................................34
EngineCoolingSystem................................................................................................38
CoolingSystemFlow..........................................................................................38
ThermostatOperation.........................................................................................40

6ENGINESYSTEMS
CoolantControlValve(CCV)assemblyoperation.......................................................40
EngineBrakeSystem...................................................................................................41
EngineBrakeControlSystemComponents..............................................................41
EngineBrakeSystemDescription..........................................................................42
EngineBrakeSystemOperation............................................................................42
ElectronicControlSystem.............................................................................................43
ElectronicControlSystemComponents..................................................................43
OperationandFunction.............................................................................43
ReferenceVoltage(VREF)..........................................................................43
SignalConditioner...................................................................................43
Microprocessor.......................................................................................43
DiagnosticTroubleCodes..........................................................................43
MicroprocessorMemory............................................................................43
ActuatorControl......................................................................................44
Actuators........................................................................................................44
CoolantControlValve(CCV).......................................................................44
ExhaustBackPressureValve(EBPV)Control..................................................44
ExhaustGasRecirculation(EGR)Valve.........................................................44
AirControlValve(ACV).............................................................................45
InletAirHeaterRelay(IAHR).......................................................................45
InletAirHeaterFuelSolenoid(IAHFS)Valve....................................................45
EngineThrottleValve(ETV)........................................................................45
FuelPressureControlValve(FPCV)..............................................................45
AftertreatmentFuelShutoffValve(AFTFSV)....................................................45
AftertreatmentPurgeAirValve(AFTPAV)........................................................45
DieselExhaustFluidDosingUnitHeater(DEFDUH)...........................................45
DieselExhaustFluidDoserValve(DEFDV)......................................................46
DieselExhaustFluidLineHeaterRelay(DEFLHR).............................................46
DieselExhaustFluidPressureLineHeater(DEFPLH).........................................46
DieselExhaustFluidReturnLineHeater(DEFRLH)...........................................46
DieselExhaustFluidReturnValve(DEFRV).....................................................46
DieselExhaustFluidSuctionLineHeater(DEFSLH)..........................................46
DieselExhaustFluidSupplyPump(DEFSP)andTemperatureSensor....................46
DieselExhaustFluidTankHeaterValve(DEFTHV).............................................46
DieselExhaustFluidUnitHeaterRelay(DEFUHR).............................................46
EngineandVehicleSensors.................................................................................46
ThermistorSensors..................................................................................46
VariableCapacitanceSensors.....................................................................48
MagneticPickupSensors...........................................................................50
PotentiometerSensors..............................................................................51
Switches...............................................................................................51
AdditionalSensors............................................................................................52
Ammonia(NH3)SensorModule....................................................................52
HumiditySensor(HS)................................................................................52
NitrogenOxides(NOx)INSensorModule.......................................................52
NitrogenOxides(NOx)OUTSensorModule....................................................52
OxygenSensor(O2S)................................................................................52

ENGINESYSTEMS7
EngineIdentication
EngineSerialNumber
Figure1Engineserialnumber
1.EngineSerialNumber(ESN)location
2.Engineemissionlabel
3.Cylinderhead
4.Flywheelhousing
5.Crankcase
TheEngineSerialNumber(ESN)islocatedonthe
frontofthecrankcase(leftside),belowthecylinder
head.
EngineSerialNumberExamples
Navistar®N13:126HM2YXXXXXXX
EngineSerialNumberCodes
126–N13withSCRengines
H–Diesel,turbocharged,ChargeAirCooler(CAC),
andelectronicallycontrolled
M2–Motortruck
Y–Huntsville,Alabama
7digitsufx–Engineserialnumbersequence
EngineEmissionLabel
Figure22010U.S.EnvironmentalProtection
Agency(EPA)exhaustemissionlabel(example)
TheU.S.EnvironmentalProtectionAgency(EPA)
exhaustemissionlabelisontopofthevalvecover
(frontleftside).TheEPAlabeltypicallyincludesthe
following:
•Modelyear
•Enginefamily,model,anddisplacement
•Advertisedbrakehorsepowerandtorquerating
•Emissionfamilyandcontrolsystems
•Valvelashspecications
•EngineSerialNumber(ESN)
•EPA,OnboardDiagnostics(OBD),EURO,and
reservedeldsforspecicapplications

8ENGINESYSTEMS
EngineAccessoryLabelsandIdentication
Plates
Thefollowingengineaccessoriesmayhave
manufacturer'slabelsoridenticationplates:
•AftertreatmentControlModule(ACM)
•AftertreatmentPurgeAirValve(AFTPAV)
•Aircompressor
•Airconditioningcompressor
•Alternator
•Coolingfanclutch
•DieselOxidationCatalyst(DOC)
•DieselParticulateFilter(DPF)
•EngineControlModule(ECM)
•HighPressure(HP)fuelpump
•Powersteeringpump
•SelectiveCatalystReduction(SCR)catalyst
•Startermotor
•Turbochargers
EngineSpecications
Navistar®N13DieselEngine
EngineConguration4stroke,inlinesixcylinderdiesel
Advertisedbrakehorsepower@rpm
•Navistar®N13SeeEPAexhaustemissionlabel
Peaktorque@rpm
•Navistar®N13SeeEPAexhaustemissionlabel
Displacement
•Navistar®N1312.4L(758in³)
Compressionratio
•Navistar®N1317.0:1
Stroke
•Navistar®N13166mm(6.54in)
Bore(sleevediameter)
•Navistar®N13126mm(4.96in)
Totalengineweight(dryweightwithouttrimoraccessories)

ENGINESYSTEMS9
•Navistar®N131087kgs(2392lbs)
Firingorder1-5-3-6-2-4
Enginerotationdirection(facingywheel)Counterclockwise
AspirationDualturbochargedandchargeaircooled
CombustionsystemDirectinjectionturbocharged
FuelsystemHigh-pressurecommonrail
Lubesystemcapacity(includinglter)40L(42qts)
•Navistar®N13
Lubesystemcapacity(overhaulonly,withlter)44L(46qts)
•Navistar®N13
EngineoilpressureatoperatingtemperaturewithSAE15W-40oil
•Lowidle
•Highidle
69kPa(10psi)min.
276-483kPa(40-70psi)
Idlespeed(noload)600rpm,nominal
Thermostatoperatingtemperature
•Primary
•Secondary
83°C-95°C(181°F-203°F)
87°C-102°C(189°F-216°F)

10ENGINESYSTEMS
HeavyDutyOnBoardDiagnostics(HD-OBD)
TheEPAhasaddednewregulationsfor2010to
reduceheavydutyvehicleemissions.TheHD-OBD
systemisdesignedspecicallyforelectronically
controlledheavydutyengines.ThegoalforHD-OBD
regulationistokeepengineemissionsinspecication
foraslongasagivenvehicleisinuse.
HD-OBDislegislatedtobeimplementedinthree
phases:
•2010:FirstengineforeachOriginalEquipment
Manufacture(OEM)becomesfullycertied.
•Theleadengineisdeterminedbyalegislated
equationbasedonprojectedsalesvolume&
usefullifeoftheengine.
•ForNavistar®,thisistheEPA2010®N13
engine.
•2013:Oneengineineachenginefamilybecomes
fullycertied.
•Thiswillbethelargeststepofthethree
phases.
•2016:AllenginesmustbefullyHD-OBDcertied.
TheHD-OBDsystemcontinuouslymonitorsforproper
engineoperation,andwillalertthevehicleoperatorto
emission-relatedfaultsusingtheMalfunctionIndicator
Lamp(MIL).
TheMILisinstalledintheElectronicInstrument
Cluster.Whenadetectedemissionsfaultoccurs,
theMILwillbeilluminated.Diagnosticinformationis
alsostoredintheEngineControlModule(ECM),and
maybeaccessedbythetechnicianfordiagnosisand
repairofthemalfunction.Diagnosticinformationis
accessedbyconnectingtheElectronicServiceT ool
(EST)tothein-cabDiagnosticConnector.
EngineDescription
TheNavistar®N13dieselengineisdesigned
forincreaseddurability,reliability,andeaseof
maintenance.
Thecylinderheadhasfourvalvespercylinderfor
increasedairow.Theoverheadvalvetrainincludes
rockerarmsandvalvebridgestooperatethefour
valves.Thefuelinjectoriscentrallylocatedbetween
thefourvalves,directingfueloverthepistonfor
improvedperformanceandreducedemissions.
Theoverheadcamshaftissupportedbyseven
bearingsinthecylinderhead.Thecamshaftgear
isdrivenfromtherearoftheengine.Theoverhead
valvetrainincludesrollerrockerarmsanddualvalves
thatopen,usingavalvebridge.
Navistar®N13enginesuseone-piecesteelpistons.
Allpistonsuseanoffsetpistonaxisandcentered
combustionbowls.Crownmarkingsshowcorrect
pistonorientationinthecrankcase.
Theone-piececrankcaseusesreplaceablewet
cylinderlinersthataresealedbydualcreviceseals.
Thecrankshafthassevenmainbearingswithfore
andaftthrustcontrolledatthesixthbearing.One
fracturedcapconnectingrodisattachedateach
crankshaftjournal.Thepistonpinmovesfreelyinside
theconnectingrodandpiston.Pistonpinretaining
ringssecurethepistonpininthepiston.Therearoil
sealcarrierispartoftheywheelhousing.
Agerotorlubeoilpumpismountedbehindthefront
coverandisdrivenbythecrankshaft.Pressurized
oilissuppliedtovariousenginecomponents.All
Navistar®N13enginesalsouseanengineoilcooler
andacartridge-styleengineoillter,whichare
installedintheenginelubeoilmodule.
Thelow-pressurefuelpumpdrawsfuelfromthe
fueltank(s)throughachassismountedlter/water
separator.Thelow-pressurefuelpumpprovidesfuel
fortheenginemountedfuelmodule.Conditioned
low-pressurefuelissuppliedfromtheenginemounted
fuelmoduletothehigh-pressurefuelpump,InletAir
Heaterfuelsolenoid,andtheAFTfueldosermodule.
Thehigh-pressurefuelsystemisadirectfuelinjected
common-railsystem.Thecommon-railincludesa
high-pressurefuelpump,twofuelrailsupplylines,
fuelrail,sixfuelinjectors,andpressurereliefvalve.
Thefuelinjectorsareinstalledinthecylinderhead
underthevalvecoverandareelectronicallyactuated
bytheECM.
Navistar®N13enginesuseadualstage,xed
geometryturbochargerassembly.Eachstage
includesaChargeAirCooler(CAC).TheHigh
Pressure(HP)turbochargerincludesapneumatically
operatedwastegate.TheLowPressureChargeAir
Cooler(LPCAC)ismountedonthelowerrightside
oftheengine,andusestheenginecoolingsystemto
regulatechargeairtemperatures.TheHighPressure
ChargeAirCooler(HPCAC)ismountedinfront

ENGINESYSTEMS11
oftheenginecoolingpackage.TheHPCACisan
air-to-airtypecooler,andrequiresnoconnectionsto
theengine'scoolingsystem.
TheExhaustGasRecirculation(EGR)system
circulatescooledexhaustintotheairinletduct.The
dualstageEGRcoolerprovidesregulatedcoolingof
theEGRgasesbeforeenteringtheairinletduct.This
coolsthecombustionprocess,andreducesNitrogen
Oxides(NOX)emissions.
Theopencrankcasebreathersystemusesa
centrifugalCrankcaseOilSeparator(CCOS)toreturn
oilmisttothecrankcase,andventthecleaned
crankcasegassestotheatmosphere.TheCCOSis
partoftheoilmodule.Thebreathersystemhasbeen
redesigned,andusesnocrankcasebreatherlter
orexternalpiping.BlowbygasesentertheCCOS
throughthesideofthecrankcase.
TheInletAirHeatersystemwarmstheincomingair
supplyduringenginecrankingandseveralminutes
aftercoldenginestartuptohelpreduceemissions.
TheNavistar®EngineBrakebyJacobs®isoptional
forNavistar®N13enginedisplacements.Theengine
brakeisacompressionreleasesystemthatprovides
additionalvehiclebrakingperformance.Theoperator
cancontroltheenginebrakefordifferentoperating
conditions.
OptionalEquipment
Optionalcoldclimatefeaturesavailableareanoilpan
heaterandacoolantheater.Bothheatersusean
electricelementtowarmengineuidsincoldweather.
Theoilpanheaterwarmsengineoiltoensure
optimumoilowtoenginecomponents.
Thecoolantheaterwarmstheenginecoolant
surroundingthecylinders.Warmedenginecoolant
increasesfueleconomyandaidsstart-upincold
weather.
ChassisMountedEquipment
•Thechassismountedfuellter/waterseparator
removesamajorityofthewaterandforeign
particlesthatmayenterthefuelsystemfromthe
supplytank(s).Thislterworkswiththeengine
mountedfuelmoduletoeliminateforeignmatter
andmoisturefromthefuelbeforeenteringthe
fuelinjectionsystem.
•TheLowTemperatureRadiator(LTR)regulates
thetemperatureoftheLPCACandthe
low-temperaturestageoftheEGRcooler.The
LTRismountedinfrontoftheradiatorcooling
package,andrequiresconnectionstotheengine
coolingsystem.
•TheHPCAClowerstemperatureaftertheairis
compressedbytheturbochargers,andhasno
connectionstotheenginecoolingsystem.The
HPCACisanair-to-aircooler.TheHPCACis
mountedinfrontoftheradiatorcoolingpackage.
•TheDieselOxidationCatalyst(DOC)oxidizes
hydrocarbonsandcarbonmonoxide,provides
heatforexhaustsystemwarm-up,aidsin
temperaturemanagementfortheDiesel
ParticulateFilter(DPF),andoxidizesNOinto
NO2forpassiveDPFregeneration.TheDOCis
monitoredbytheAftertreatmentControlModule
(ACM)usingoneDieselOxidationCatalystInlet
Temperature(DOCIT)sensorpositionedatthe
DOCinlet,andoneDieselParticulateFilterInlet
Temperature(DPFIT)sensorpositionedatthe
DPFinlet.
•TheDPFtemporarilystorescarbon-based
particulates,oxidizesstoredparticulates,stores
non-combustibleash,andprovidesrequired
exhaustbackpressureforproperengine
performance.TheDPFismonitoredbytheACM
usingtheDOC/DPFtemperaturesensormodule
installedontheDPF,andtheDieselParticulate
FilterDifferentialPressure(DPFDP)/outlet
pressuresensorinstalledonorneartheDPF .
•TheSelectiveCatalystReduction(SCR)catalyst
oxidizesNitrogenOxides(NOx)intoNitrogengas
andwater.TheSCRcatalystismonitoredby
theACMusingaNOxINsensormoduleinstalled
aftertheHPturbochargeroutletpipe,andaNOx
OUTsensormoduleinstalledaftertheoutletofthe
SCRcatalyst.Anammonia(NH3)sensorprovides
feedbacktotheACMrelatedtoDieselExhaust
Fluid(DEF)injectionintotheSCRcatalyst.

12ENGINESYSTEMS
AirManagementSystem
Figure3AirManagementSystem
1.ExhaustGasRecirculation
Temperature(EGRT)sensor
2.IntakeManifoldPressure(IMP)
sensor
3.EngineThrottleValve(ETV)
4.ChargeAirCoolerOutlet
Temperature(CACOT)Sensor
5.EGRcooler
6.IntakeManifoldT emperature
(IMT)sensor
7.EGRvalve
8.Turbocharger2Compressor
InletSensor(TC2IS)
9.Airlterhousing
10.HumiditySensor(HS)/InletAir
Temperature(IAT)sensor
11.LowPressure(LP)turbocharger
12.ExhaustBackPressureValve
(EBPV)
13.OxygenSensor(O2S)
14.HighPressure(HP)turbocharger
15.HPturbochargerwastegate
16.Exhaustmanifold
17.Cylinderhead

ENGINESYSTEMS13
Airow
Airowsthroughtheairlterassemblyandenters
theLow-Pressure(LP)turbocharger.TheLP
turbochargerincreasesairpressureandtemperature
beforeenteringtheLowPressureChargeAirCooler
(LPCAC).Cooledandcompressedairthenowsfrom
theLPCACintotheHighPressure(HP)turbocharger
(compressorinlet).Hotandhighlycompressedair
owsfromtheHPturbocharger(compressoroutlet)
intotheHighPressureChargeAirCooler(HPCAC)
whereitiscooled,andintotheintakethrottleduct,
andcontinuesthroughtheEngineThrottleValve
(ETV).TheHPandLPturbochargerscanincrease
pressuresupto345kPa(50psi).
IftheExhaustGasRecirculationValve(EGRV)is
open,exhaustgasespassthroughtheEGRcooler
andintotheintakethrottleductwhereitismixedwith
lteredair.Thismixtureowsintotheintakemanifold,
andthenthecylinderhead.Theintakemanifoldisan
integralpartofthecylinderheadcasting.
Duringcoldweather,theInletAirHeatersystem
activatestheheaterelement,vaporizingandigniting
smallquantitiesoffuelintotheairinletduct.
Aftercombustion,exhaustgasesexitthroughthe
cylinderheadexhaustvalvesandports.Theexhaust
gasisforcedthroughtheexhaustmanifoldwhere,
dependingonEGRVposition,itissplitbetween
theEGRsystemandtheexitpaththroughtheHP
turbocharger,LPturbocharger,andExhaustBack
PressureValve(EBPV).
TheEBPVisoperatedbytheAirControlValve(ACV),
apneumaticactuator.WhentheACVisapplied,
theEBPVrestrictsowandincreasesexhaustback
pressure.OperationoftheEBPViscontrolledbythe
ECMusingtheACVandtheTurbocharger1Turbine
OutletPressure(TC1TOP)sensor.WhentheEBPV
isopened,exhaustbackpressureisreleased.
Exhaustgasesexitingtheengineowthroughthe
EBPV,thenthroughthevehicleAftertreatment(AFT)
system,andouttheexhausttailpipe.

14ENGINESYSTEMS
Turbochargers
Figure4HighandLowPressureTurbochargerComponents–InnerandOuterviews
1.HighPressure(HP)turbocharger
compressorinlet
2.HPturbochargerturbineinlet
3.LPturbochargerturbineoutlet
4.HPturbocharger
5.HPturbochargerwastegate
actuator
6.LowPressure(LP)turbocharger
7.Turbochargeroilsupplytube
8.LPturbochargercompressor
outlet
9.Oilreturntube
10.LPturbochargercompressor
inlet
11.HPturbochargercompressor
outlet
Navistar®N13enginesareequippedwitha
pneumaticallyregulatedtwo-stageturbocharger
system.TheHighPressure(HP)andLowPressure
(LP)turbochargersareinstalledinparallelontheright
sideoftheengine.
Intakeairow:FilteredairenterstheLPcompressor,
whereitiscompressedanddirectedtotheLow
PressureChargeAirCooler(LPCAC).Cooled
compressedairthenenterstheHPcompressor,
whereitisfurthercompressedanddirectedinto
theHighPressureChargeAirCooler(HPCAC).
CompressedairthengoesthroughtheEngine
ThrottleValve(ETV)andtheintakethrottleduct.This
systemprovideshighchargeairpressuretoimprove
engineperformanceandtohelpreduceemissions.
Exhaustgasow:TheHPturbochargeris
connectedtotheexhaustmanifoldthroughtheHP
turbineinlet.ExhaustgasesexittheHPturbine
outletandaredirectedtotheLPturbineinlet.The
HPturbochargerisequippedwithawastegate,
whichiscontrolledbyapneumaticactuator.TheHP
turbochargerwastegateisusedtoregulateboostby
controllingtheamountofexhaustgasthatbypasses
theturbineoftheturbocharger.Whenboostdemand