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Fuel Supply System Features

HorizontalFuelConditioningModule(HFCM)

(1)ChassisMounted10MicronFuelFilter

(1)EngineMounted4MicronFuelFilter

WaterSeparator

FuelCooler

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Fuel supply system

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Fuel Supply System Features

ThefuelsupplysystemusesanewHorizontalFuelConditioningModule(HFCM).TheHFCMfiltersfuel,separateswater,senseswater,andrecirculateswarmfuelthroughthepumpduringcoolfuelconditions.

The6.4LPowerStrokeDieselalsouses2fuelfiltersandastandalonefuelcoolersystem.

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Fuel supply system

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Fuel FlOW

Engine Fuel Flow

Thefuelpump,locatedintheHorizontalFuelConditioningModule(HFCM),drawsfuelfromthefueltankandthrougha10micronfuelfilter.

TheHFCMcontainsthefuelpump,filter,waterseparator,waterinfuelswitch,fueldrain,anddieselthermorecirculationvalve(DTRM).

TheDTRMcontrolstheflowoffuelreturnedfromtheenginemountedfilterthroughtheHFCM.Ifthefuelbeingdrawnfromthefueltankiscoolerthanaspecifiedtemperaturethenreturnfuelfromtheengineisrecirculatedintotheinletofthepump.

AfterthefuelisconditionedbytheHFCM,thecleanpressurizedfuelissenttotheenginemountedfuelfilterassemblywhereparticleslargerthan4micronarefilteredoutofthefuel.

TheenginemountedfuelfilterassemblyalsoregulatesfuelpressurebyreleasingexcesspressureviaareturnfuellinebacktotheHFCM.Theenginemountedfuelfilteralsocontainsairbleedorificestoremoveairandreturnittothetank.

AfterthefuelisfiltereditisroutedtotheInternalTransferPump(ITP).

TheITPislocatedinsidethehighpressurefuelinjectionpumpandisusedtoincreasethefuelpressuresuppliedtothehighpressurefuelinjectionpumpsthree(3)internalpistons.

Afterthefuelispressurizeditisroutedtothehighpressurefuelrailsandtothefuelinjectorsviahighpressurefuelsupplytubes.

APressureControlValve(PCV)locatedintheoutletsideofthehighpressurefuelinjectionpumpcontrolsthefuelpressurebydumpingexcessfuelintothefuelreturnline.

AFuelRailPressure(FRP)sensorlocatedintherightsidefuelrailmonitorsthefuelpressure.

Returnfuelfromtheinjectorsisroutedthroughadrilledpassagefromeachcylinderheadwhereitisthenunitedwithreturnfuelfromthehighpressurefuelinjectionpumpbeforebeingsenttothefuelcoolerandbacktotheenginemountedfuelfilter.

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Fuel Supplyto HFCM

Fuel Returnto Tank

Fuel Returnto HFCM

Fuel Supplyto Engine

To Filter/Pump(suction side)NOTE: Drilled Passage Hidden

Pump Outlet

Fuel Return Directed via DTRM to Tank or Back Through Pump

Fuel Cap Fuel Filter Fuel Pump

Fuel InletCheck Valve

DTRM

Manifold

Drain Valve

Fuel PumpPower

Water In Fuel Sensor51

Fuel supply system

HFCM (Horizontal Fuel Conditioning Module) TheHFCMismountedtotheframerailonthedriversside.

TheHFCMisasinglemodulethatperformsmultipletasks.Itseparateswaterfromthefuel,senseswhenwaterispresentinthefuel,filtersparticulatesfromthefuel,andcreatesthefuelflowneededtosupplyfueltotheenginemountedfuelfilter.

ADTRM(DieselThermoRecirculationModule)isalsopartoftheHFCM.Itrecirculatesfuelthatreturnsfromtheenginemountedfuelfilterbackintothefuelfilterinsteadofbacktothetank.

HFCM Fuel Flow FuelisdrawnintotheHFCMfromthefueltankviaa

supplyline.

Fuelentersthefilterhousingviaaone-waycheckvalve.

Onceinthefilterhousing,waterisseparatedfromthefuel.Iflargeamountsofwaterarefoundinthefuel,asensorintheseparatorwarnstheoperatorofthisconditionbyilluminatingalightonthedash.

Fuelisthendrawnthroughthe10micronfuelfilterandintothefuelpump.

Conditionedpressurizedfuelisthensuppliedtotheenginemountedfuelfilterviaafuelsupplyline.Thepumphasaninternalregulatorthatlimitsfuelpressureto24psi.

FuelreturningfromthepressureregulatorontheenginemountedfuelfiltercomesintotheHFCMandaDTRMeitherallowsthefueltoreturntothetankorreturnsittotheunfilteredsideofthefuelfilterintheHFCM.TheDTRMstartstoopen(recirculatingfuelbackintothepump)at80F(27C)andisfullyopenat50F(10C).

HFCM Components

TheHFCMiscomposedofsix(6)maincomponents:

- Housing

- FuelFilter(10micron)

- FuelCap

- ElectricFuelPump

- Manifold(containsthefuelinletcheckvalve)

- DieselThermoRecirculationModule(DTRM) isalsopartoftheHFCM.Itrecirculatesfuelthat returnsfromtheenginemountedfuelfilterback intothefuelfilterinsteadofbacktothetank.

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Fuel Return Banjo Bolt

Filter Housing

Engine Mounted Fuel Filter

Filter Cap

Fuel Supply

Fuel PressureRegulator LocatedInside StandpipeAssembly

Fuel Return to Tank

Fuel Returnfrom Cooler

Filtered FuelOutlet

Fuel Temperature Sensor (FTS)

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fuel supply system

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Engine Mounted Fuel Filter

Anenginemountedfuelfilterismountedtotheintakemanifold.

Theenginemountedfuelfilterisa4microncartridgestylefilter.

Italsoincorporatesafuelpressureregulator(inthestandpipe)andanairbleed.FuelfromtheregulatorisreturnedtotheHFCM.

NOTE: Please exercise extreme cleanliness when servicing the fuel filter.

Fuel Pressure Regulator

Thefuelpressureregulatorislocatedinsidetheenginemountedfuelfilterhousinginthestandpipe.

ItregulatesfuelpressurebyroutingunfilteredfuelfromthefilterhousingtotheHFCMviaaspringloadedpoppetstylevalve.

Thecrackingpressure(pressureatwhichthevalvebeginstoopen)ofthevalveis2psi+\-0.5psi.Actualfuelpressuremaybeaboveorbelowthisspecification.

Theregulatedpressureofthevalveis3psi+/-0.5psi.Actualfuelpressuremaybeaboveorbelowthisspecification.

NOTE: The fuel pressure regulator is NOT serviceable separate from the housing! If the regulator needs to be replaced, then the entire housing must be replaced.

Fuel Return Banjo Fittings

Thefuelreturnlines(locatedonthefrontofeachcylinderhead)utilizeabanjobolttoroutethereturnfuelbacktothefuelsystem.

NOTE: The 6.0L Power Stroke Diesel utilized a banjo bolt with a check valve inside. Do not interchange the 6.0L banjo bolt with the 6.4L banjo bolt.

NOTE: The 6.4L Power Stroke Diesel uses an open banjo bolt with no check valve. The check valves are no longer needed since the drilled passages in the cylinder heads are now utilized as fuel return passages.

Fuel supply system

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