Navistar MaxxForce DT - Engine Description and Features

SECTION1–ENGINESYSTEMS
EngineDescription
MaxxForce
®
DT,9,&10enginesareinlinesixcylinderdiesel
engineswhichhavebeendesignedforincreaseddurability,
reliability,andeaseofmaintenance.
AirManagementSystem
MaxxForce
®
DT,9,&10enginesuseanelectronicallycontrolled
twostageturbochargingsystemconsistingofahigh-pressure
andlow-pressureturbocharger.Thehighandlow-pressure
turbochargersareinstalledasanassemblyontheexhaust
manifold.
AChargeAirCooler(CAC)isanair-to-airheatexchangerwhich
coolsandincreasesthedensityoftheaircharge.Inaddition
totheCAC,theMaxxForce
®
DT,9,&10dieselengineshave
anenginemountedinterstagecooler.Thecoolerhasalow
temperatureradiatorandalowtemperaturethermostat.
TheExhaustGasRecirculation(EGR)systemcirculatescooled
exhaustintotheintakeairstreamintheintakemanifold.This
coolsthecombustionprocessandreducestheformationofNO
X
engineemissions.
ColdStartAssist
TheInletAirHeater(IAH)systemwarmstheincomingairsupply
toaidcoldenginestartingandreducewhitesmokeduring
warm-up.TheIAHsystemwillinitiallyilluminatetheWAITTO
STARTlamp.Whenthelampturnsoff,theenginecanbe
started.
CrankcaseAssembly
Thecamshaftissupportedbyfourinsertbushingspressedinto
thecrankcase.Thecamshaftgearisdrivenfromthefrontofthe
engine.Athrustangeislocatedbetweenthecamshaftandthe
drivegear.Theoverheadvalvetrainincludesmechanicalroller
lifters,pushrods,rockerarms,anddualvalvesthatopenusing
avalvebridge.
Agerotorlubeoilpumpismountedonthefrontcoverandis
drivenbythecrankshaft.Pressurizedoilissuppliedtoengine
componentsandthehigh-pressureinjectionsystem.AllNavistar
DT,9,and10enginesuseanengineoilcoolerandspin-on
engineoillter.
MaxxForce
®
DTenginesuseaonepiecealuminumalloypiston.
TheMaxxForce
®
DT,9,&10enginesuseaonepiecesteel
piston.Thepistonshavea0.0offsetandarefullysymmetric.
Theonepiececrankcaseusesreplaceablewetcylindersleeves
thataresealedbyasinglecreviceseal.Someapplications
includeacrankcaseladderwhichisdesignedtoabsorbheavier
loadsandreduceenginenoise.
Aclosedcrankcasebreathersystemusesanenginemounted
oilseparatortoreturnoiltothecrankcaseandventcrankcase
pressureintotheintakesystem.
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