2003 DODGE RAM water pump

FUEL DELIVERY - DIESEL
TABLE OF CONTENTS
page page
FUEL DELIVERY - DIESEL
DESCRIPTION - DIESEL FUEL SYSTEM.....57
STANDARD PROCEDURE
STANDARD PROCEDURES - WATER
DRAINING AT FUEL FILTER..............57
STANDARD PROCEDURES - CLEANING
FUEL SYSTEM PARTS.................58
STANDARD PROCEDURE - FUEL SYSTEM
PRIMING............................59
SPECIFICATIONS
FUEL SYSTEM PRESSURE - DIESEL......60
FUEL INJECTOR FIRING ORDER - DIESEL . 60
SPECIAL TOOLS
DIESEL FUEL SYSTEM.................60
FUEL FILTER / WATER SEPARATOR
DESCRIPTION.........................61
OPERATION...........................61
REMOVAL.............................61
INSTALLATION.........................62
FUEL HEATER
DESCRIPTION.........................63
OPERATION...........................63
DIAGNOSIS AND TESTING - FUEL HEATER . . . 63
REMOVAL
REMOVAL/INSTALLATION...............64
FUEL HEATER RELAY
DESCRIPTION.........................64
OPERATION...........................64
REMOVAL.............................64
INSTALLATION.........................64
FUEL INJECTION PUMP
DESCRIPTION.........................64
OPERATION...........................64
DIAGNOSIS AND TESTING - FUEL INJECTION
PUMP TIMING........................65
REMOVAL.............................65
INSTALLATION.........................67
FUEL LEVEL SENDING UNIT / SENSOR
DESCRIPTION.........................68
OPERATION...........................68
REMOVAL
REMOVAL/INSTALLATION...............68FUEL LINES
DESCRIPTION.........................69
OPERATION...........................69
DIAGNOSIS AND TESTING - HIGH-
PRESSURE FUEL LINE LEAKS...........69
REMOVAL.............................69
INSTALLATION.........................71
FUEL PRESSURE SENSOR
DESCRIPTION.........................72
OPERATION...........................72
REMOVAL.............................72
INSTALLATION.........................72
FUEL PRESSURE LIMITING VALVE
DESCRIPTION.........................72
OPERATION...........................72
REMOVAL.............................72
INSTALLATION.........................73
FUEL TANK
DESCRIPTION - DIESEL..................73
REMOVAL - DIESEL.....................73
INSTALLATION - DIESEL.................74
FUEL TANK MODULE
DESCRIPTION.........................75
OPERATION...........................75
REMOVAL.............................75
INSTALLATION.........................75
FUEL TRANSFER PUMP
DESCRIPTION.........................75
OPERATION...........................76
REMOVAL.............................76
INSTALLATION.........................76
CASCADE OVERFLOW VALVE
DESCRIPTION.........................77
OPERATION...........................77
REMOVAL
REMOVAL/INSTALLATION...............77
WATER IN FUEL SENSOR
DESCRIPTION.........................77
OPERATION...........................78
REMOVAL.............................78
FUEL DRAIN CIRCUIT
OPERATION...........................78
14 - 56 FUEL DELIVERY - DIESELDR

FUEL DELIVERY - DIESEL
DESCRIPTION - DIESEL FUEL SYSTEM
The fuel system used on the Cummins engine is an
electronically controlled, Bosch HPCR (High-Pressure
Common Rail) system. The HPCR system consists of
five main components:
²Electric Fuel Transfer (lift) Pump
²Fuel Pump/Gear Pump (attached to fuel injec-
tion pump)
²High-Pressure Fuel Injection Pump
²Fuel Injection Rail
²Fuel Injectors
Also to be considered as part of the overall fuel
system are:
²Accelerator Pedal
²Air Cleaner Housing/Element
²Fuel Drain Manifold (passage)
²Fuel Drain Valve (at filter)
²Fuel Filter/Water Separator
²Fuel Heater
²Fuel Heater Relay
²Fuel Level (gauge) Sending Unit
²Fuel Tank
²Fuel Tank Module (containing fuel gauge send-
ing unit and separate fuel filter located at bottom of
tank module)
²Fuel Tank Filler/Vent Tube Assembly
²Fuel Tank Filler Tube Cap
²Fuel Tubes/Lines/Hoses
²High-Pressure Fuel Injector Lines
²In-Tank Fuel Filter (at bottom of fuel tank mod-
ule)
²Low-Pressure Fuel Supply Lines
²Low-Pressure Fuel Return Line
²Overflow Valve
²Quick-Connect Fuel Line Fittings
²Throttle Cable
²Water Draining (maintenance)
²Water-In-Fuel (WIF) Sensor
The fuel injection pump supplies high pressure to
the fuel rail independent of engine speed. This high
pressure is then accumulated in the fuel rail. High
pressure fuel is constantly supplied to the injectors
by the fuel rail. The Engine Control Module (ECM)
controls the fueling and timing of the engine by actu-
ating the injectors.Fuel enters the system from the electric fuel trans-
fer (lift) pump, which is attached to the fuel filter
assembly. Fuel is forced through the fuel filter ele-
ment and then enters the Fuel Pump/Gear Pump,
which is attached to the rear of the fuel injection
pump. The Fuel Pump/Gear Pump is a low-pressure
pump and produce pressures ranging from 551.5 kpa
(80 psi) to 1241 kpa (180) psi. Fuel then enters the
fuel injection pump. Low pressure fuel is then sup-
plied to the FCA (Fuel Control Actuator).
The FCA is an electronically controlled solenoid
valve. The ECM controls the amount of fuel that
enters the high-pressure pumping chambers by open-
ing and closing the FCA based on a demanded fuel
pressure. The FPS (Fuel Pressure Sensor) on the fuel
rail provides the actual fuel pressure. When the
actuator is opened, the maximum amount of fuel is
being supplied to the fuel injection pump. Any fuel
that does not enter the injection pump is directed to
the overflow valve. The overflow valve regulates how
much excess fuel is used for lubrication of the pump
and how much is returned to the tank through the
drain manifold.
Fuel entering the injection pump is pressurized to
between 300 - 1600 bar by three radial pumping
chambers. The pressurized fuel is then supplied to
the fuel rail.
Some fuel system components are shown in.
WARNING: HIGH-PRESSURE FUEL LINES DELIVER
DIESEL FUEL UNDER EXTREME PRESSURE FROM
THE INJECTION PUMP TO THE FUEL INJECTORS.
THIS MAY BE AS HIGH AS 160,000 KPA (23,206
PSI). USE EXTREME CAUTION WHEN INSPECTING
FOR HIGH-PRESSURE FUEL LEAKS. INSPECT FOR
HIGH-PRESSURE FUEL LEAKS WITH A SHEET OF
CARDBOARD. HIGH FUEL INJECTION PRESSURE
CAN CAUSE PERSONAL INJURY IF CONTACT IS
MADE WITH THE SKIN.
Certain fuel system components can be found in
(Fig. 1), or (Fig. 2).
STANDARD PROCEDURE
STANDARD PROCEDURES - WATER DRAINING
AT FUEL FILTER
Refer to Fuel Filter/Water Separator removal/in-
stallation for procedures.
DRFUEL DELIVERY - DIESEL 14 - 57

STANDARD PROCEDURES - CLEANING FUEL
SYSTEM PARTS
CAUTION: Cleanliness cannot be overemphasized
when handling or replacing diesel fuel system com-
ponents. This especially includes the fuel injectors,
high-pressure fuel lines and fuel injection pump.
Very tight tolerances are used with these parts. Dirt
contamination could cause rapid part wear and pos-
sible plugging of fuel injector nozzle tip holes. This
in turn could lead to possible engine misfire.Always wash/clean any fuel system component
thoroughly before disassembly and then air dry.
Cap or cover any open part after disassembly.
Before assembly, examine each part for dirt, grease
or other contaminants and clean if necessary. When
installing new parts, lubricate them with clean
engine oil or clean diesel fuel only.
Fig. 1 DIESEL FUEL SYSTEM COMPONENTS
1 - ENGINE COOLANT TEMPERATURE (ECT) SENSOR 14 - FUEL SUPPLY LINE (LOW-PRESSURE, TO ENGINE)
2 - THROTTLE LEVER BELLCRANK AND APPS (ACCELERATOR
PEDAL POSITION SENSOR)15 - FUEL RETURN LINE CONNECTION (TO FUEL TANK)
3 - INTAKE MANIFOLD AIR HEATER/ELEMENTS 16 - FUEL DRAIN TUBE
4 - FUEL PRESSURE SENSOR 17 - OIL PRESSURE SENSOR
5 - FUEL LIMITING VALVE 18 - ENGINE CONTROL MODULE (ECM)
6 - HIGH-PRESSURE FUEL LINES 19 - FUEL INJECTION PUMP
7 - FUEL HEATER 20 - CRANKSHAFT POSITION (ENGINE SPEED) SENSOR
8 - HIGH-PRESSURE FUEL INJECTOR RAIL 21 - CAMSHAFT POSITION SENSOR (CMP)
9 - FUEL HEATER TEMPERATURE SENSOR (THERMOSTAT) 22 - FUEL CONTROL ACTUATOR (FCA)
10 - FUEL FILTER/WATER SEPARATOR 23 - CASCADE OVERFLOW VALVE
11 - FUEL TRANSFER (LIFT) PUMP
12 - FUEL DRAIN MANIFOLD
13 - DRAIN VALVE
14 - 58 FUEL DELIVERY - DIESELDR
FUEL DELIVERY - DIESEL (Continued)

FUEL FILTER / WATER
SEPARATOR
DESCRIPTION
The fuel filter/water separator assembly is located
on left side of engine above starter motor. The assem-
bly also includes the fuel heater and Water-In-Fuel
(WIF) sensor, and fuel transfer pump.
OPERATION
The fuel filter/water separator protects the fuel
injection pump by removing water and contaminants
from the fuel. The construction of the filter/separator
allows fuel to pass through it, but helps prevent
moisture (water) from doing so. Moisture collects at
the bottom of the canister.
Refer to the maintenance schedules for the recom-
mended fuel filter replacement intervals.
For draining of water from canister, refer to Fuel
Filter/Water Separator Removal/Installation section.A Water-In-Fuel (WIF) sensor is attached to side of
canister. Refer to Water-In-Fuel Sensor Description/
Operation.
The fuel heater is installed into the top of the fil-
ter/separator housing. Refer to Fuel Heater Descrip-
tion/Operation.
REMOVAL
Refer to maintenance schedules in this manual for
recommended fuel filter replacement intervals.
Draining water from fuel filter/water separa-
tor housing:
The housing drain valve (Fig. 3) or (Fig. 4) serves
two purposes. One is topartiallydrain filter hous-
ing of excess water. The other is tocompletelydrain
housing for fuel filter, drain valve, heater element, ,
water-in-fuel sensor replacement or transfer pump
replacement.
The filter housing should be partially drained
whenever water-in-fuel warning lamp remains illumi-
nated. (Note that lamp will be illuminated for
approximately two seconds when ignition key is ini-
tially placed in ON position for a bulb check).
(1) A drain hose (Fig. 3) or (Fig. 4) is located at
bottom of drain valve. Place drain pan under drain.
(2)With engine not running,rotate drain valve
handle rearward to OPEN (DRAIN) position. Hold
drain valve open until all water and contaminants
have been removed and clean fuel exits.
(3) If drain valve, fuel heater element or Water-In-
Fuel (WIF) sensor is being replaced, drain housing
completely. Dispose of mixture in drain pan according
to applicable regulations.
(4) After draining operation, push valve handle
forward to CLOSE position.
(5)Fuel Filter Replacement:The fuel filter is
located inside of the fuel filter housing.
(a) Clean all debris from around canister.
(b) Remove filter lid (Fig. 5) using a socket.
Attach socket to large hex on top of lid (Fig. 5).
Rotate counter-clockwise for removal. Remove
o-ring.
(c) Remove filter element by twisting element
sideways from filter lid.
(6)Water-In-Fuel (WIF) Sensor Replacement:
The WIF sensor is located on the side of the fuel fil-
ter housing (Fig. 3) or (Fig. 4).
(a) Disconnect electrical connector at sensor.
(b) Clean area around sensor.
(c) Remove sensor by rotating counter-clockwise.
(d) Check condition of sensor o-ring. Replace if
damaged.
(7)Fuel Heater Element Replacement:The
heater element is located in the fuel filter housing
(Fig. 3) or (Fig. 4).
(a) Remove fuel filter. See previous steps.
FUEL INJECTOR TUBE (CONNECTOR) REMOVER -
#9015
SPANNER WRENCH (FUEL TANK MODULE
REMOVAL/INSTALLATION) - #6856
ENGINE ROTATING (BARRING) TOOL - #7471B
(ALSO PART OF KIT #6860)
DRFUEL DELIVERY - DIESEL 14 - 61
FUEL DELIVERY - DIESEL (Continued)

heater. The heater can be check at room tempera-
ture. Operating range is 0.3 Ð 0.45 Ohms.
(3) Replace heater if resistance is not within oper-
ating range.
(4) If heater is within operating range, replace
heater thermostat.
REMOVAL
REMOVAL/INSTALLATION
The fuel heater/element/sensor assembly is located
inside of the fuel filter housing. Refer to Fuel Filter/
Water Separator Removal/Installation for procedures.
FUEL HEATER RELAY
DESCRIPTION
The fuel heater relay is located in Power Distribu-
tion Center (PDC) (Fig. 6). Refer to label on inside of
PDC cover for relay location.
OPERATION
Battery voltage to operate the fuel heater element
is supplied from the ignition switch through the fuel
heater relay.The fuel heater element and fuel
heater relay are not computer controlled.
REMOVAL
The fuel heater relay is located in the Power Dis-
tribution Center (PDC) (Fig. 7). Refer to label under
PDC cover for relay location.
(1) Remove PDC cover.
(2) Remove relay from PDC.(3) Check condition of relay terminals and PDC
connector terminals for damage or corrosion. Repair
if necessary before installing relay.
(4) Check for pin height (pin height should be the
same for all terminals within the PDC connector).
Repair if necessary before installing relay.
INSTALLATION
The fuel heater relay is located in the Power Dis-
tribution Center (PDC) (Fig. 7). Refer to label under
PDC cover for relay location.
(1) Install relay to PDC.
(2) Install cover to PDC.
FUEL INJECTION PUMP
DESCRIPTION
A Robert Bosch high-pressure fuel injection pump
is used. The pump is attached to the back of the tim-
ing gear cover at the left / rear side of the engine.
OPERATION
The fuel injection pump supplies high pressure to
the fuel rail independent of engine speed. This high
pressure is then accumulated in the fuel rail. High
pressure fuel is constantly supplied to the injectors
by the fuel rail. The Engine Control Module (ECM)
controls the fueling and timing of the engine by actu-
ating the injectors.
Fuel enters the system from the electric fuel trans-
fer (lift) pump, which is attached to the fuel filter
assembly. Fuel is forced through the fuel filter ele-
ment and then enters the Fuel Pump/Gear Pump,
which is attached to the rear of the fuel injection
Fig. 6 POWER DISTRIBUTION CENTER LOCATION
1 - CLIP
2 - BATTERY
3 - TRAY
4 - NEGATIVE CABLE
5 - POSITIVE CABLE
6 - CLIP
7 - FENDER INNER SHIELD
8 - POWER DISTRIBUTION CENTER
Fig. 7 POWER DISTRIBUTION CENTER LOCATION
1 - CLIP
2 - BATTERY
3 - TRAY
4 - NEGATIVE CABLE
5 - POSITIVE CABLE
6 - CLIP
7 - FENDER INNER SHIELD
8 - POWER DISTRIBUTION CENTER
14 - 64 FUEL DELIVERY - DIESELDR
FUEL HEATER (Continued)

FUEL TANK MODULE
DESCRIPTION
An electric fuel pump isnot usedin the fuel tank
module for diesel powered engines. Fuel is supplied
by the engine mounted fuel transfer (lift) pump.
The fuel tank module is installed in the top of the
fuel tank (Fig. 23). The fuel tank module contains
the following components:
²Fuel reservoir
²A separate in-tank fuel filter
²Fuel gauge sending unit (fuel level sensor)
²Fuel supply line connection
²Fuel return line connection
²Auxiliary non-pressurized fitting
OPERATION
Refer to Fuel Gauge Sending Unit.
REMOVAL
(1) Drain and remove fuel tank. Refer to Fuel
Tank Removal/Installation.
(2) Thoroughly clean area around tank module at
top of tank.
(3) The plastic fuel tank module locknut is
threaded onto fuel tank. Install Special Tool 6856 tolocknut and remove locknut (Fig. 24). The fuel tank
module will spring up when locknut is removed.
(4) Remove module from fuel tank.
INSTALLATION
CAUTION: Whenever the fuel tank module is ser-
viced, the rubber gasket must be replaced.
(1) Thoroughly clean locknut and locknut threads
at top of tank.
(2) Using new gasket, carefully position fuel tank
module into opening in fuel tank.
(3) Position locknut over top of fuel tank module.
Install locknut finger tight.
(4) When looking down at tank from drivers side of
tank, the fuel line connectors and fuel gauge electri-
cal connector should all be pointed to drivers side of
vehicle. Rotate and align if necessary before tighten-
ing locknut.This step must be performed to pre-
vent the module's float from contacting side of
fuel tank.
(5) Tighten locknut to 24 - 44 N´m (18 - 32 ft. lbs.)
torque.
(6) Install fuel tank. Refer to Fuel Tank Removal/
Installation.
FUEL TRANSFER PUMP
DESCRIPTION
The fuel transfer pump (fuel lift pump) is attached
to the rear of the fuel filter/water separator housing.
The 12±volt electric pump is operated and controlled
by the Engine Control Module (ECM).
Fig. 23 FUEL TANK MODULE - DIESEL
1 - TOP OF FUEL TANK
2 - AUX. FITTING
3 - ELEC. CONNECTOR
4 - FUEL TANK MODULE (TOP)
5 - LOCKNUT
6 - FUEL SUPPLY LINE
7 - FUEL RETURN LINE
Fig. 24 LOCKNUT REMOVAL/INSTALLATION -
TYPICAL MODULE
1 - SPECIAL TOOL 6856
2 - LOCKNUT
DRFUEL DELIVERY - DIESEL 14 - 75

OPERATION
The purpose of the fuel transfer pump is to supply
(transfer) a low-pressure fuel source:fromthe fuel
tank,throughthe fuel filter/water separator andto
the fuel injection pump. Here, the low-pressure is
raised to a high-pressure by the fuel injection pump
for operation of the high-pressure fuel injectors.
Check valves within the pump, control direction of
fuel flow and prevent fuel bleed-back during engine
shut down.
Maximum current flow to the pump is 5 amperes.
With the engine running, the pump has a 100 per-
cent duty-cycle with a minimum pressure of 11.5 psi.
The transfer pump is self-priming: When the key is
first turned on (without cranking engine), the pump
will operate for approximately 1/2 second and then
shut off. The pump will also operate for up to 25 sec-
onds after the starter is engaged, and then disen-
gaged and the engine is not running. The pump
shuts off immediately if the key is on and the engine
stops running.
The fuel volume of the transfer pump will always
provide more fuel than the fuel injection pump
requires. Excess fuel is returned from the injection
pump through an overflow valve, and then back to
the fuel tank.
REMOVAL
The fuel transfer pump (fuel lift pump) is attached
to the rear of the fuel filter/water separator housing
(Fig. 25).
(1) Drain fuel from fuel filter housing. Refer to
Fuel Filter/Water Separator - Removal. See Draining.
(2) Disconnect electrical connector (Fig. 25) from
fuel transfer pump.
(3) Disconnect fuel tank supply line from fuel
transfer pump extension line. Do this at disconnec-
tion point at inside of left inner frame rail (Fig. 26).
Refer to quick-connect fittings for procedures.The
fuel line extension is permanently attached to
the transfer pump. Do not attempt to discon-
nect fuel line at transfer pump.
(4) Remove 4 pump mounting bolts (hex-allen),
and remove pump from fuel filter housing.
(5) Confirm that transfer pump o-ring is also
removed from fuel filter housing.
INSTALLATION
(1) Install a new o-ring to fuel transfer pump.
(2) Lubricate o-ring and OD of transfer pump inlet
connector.
(3) Position fuel transfer pump onto fuel filter
housing.Do not use mounting bolts to draw
transfer pump to filter housing.
Fig. 25 FUEL TRANSFER (LIFT) PUMP
1 - FILTER HOUSING
2 - ELEC. CONNECTOR
3 - FUEL TRANSFER (LIFT) PUMP
4 - FUEL LINE EXTENTION
5 - MOUNTING BOLTS (4)
Fig. 26 TRANSFER PUMP FUEL LINE CONNECT
1 - LEFT INNER FRAME RAIL
2 - FUEL RETURN LINE
3 - FUEL SUPPLY LINE
4 - QUICK-CONNECT FITTING
14 - 76 FUEL DELIVERY - DIESELDR
FUEL TRANSFER PUMP (Continued)

(4) Be sure pump is positioned flat to fuel filter
housing. Install mounting bolts and evenly tighten to
7 N´m (61 in. lbs.).
(5) Connect fuel line extension at fuel supply line.
(6) Connect electrical connector to pump.
(7)Prime System:Cycle key to actuate transfer
pump or use DRB II Scan Tool to actuate transfer
pump. Check for leaks.
(8) Operate engine and check for fuel leaks.
CASCADE OVERFLOW VALVE
DESCRIPTION
The cascade overflow valve is located on the top/
rear side of the fuel injection pump (Fig. 27).
OPERATION
When the fuel control actuator (FCA) is opened,
the maximum amount of fuel is being delivered to
the fuel injection pump. Any fuel that does not enter
the injection pump is directed to the cascade overflow
valve. The cascade valve regulates how much excess
fuel is used for lubrication of the injection pump, and
is also used to route excess fuel through the drain
circuit and back into the fuel tank.
REMOVAL
REMOVAL/INSTALLATION
The cascade overflow valve is not serviced sepa-
rately.
WATER IN FUEL SENSOR
DESCRIPTION
The Water-In-Fuel (WIF) sensor is located on the
side of the fuel filter/water separator canister (Fig.
28), or (Fig. 29).
Fig. 27 OVERFLOW VALVE
1 - BANJO BOLTS
2 - PUMP MOUNTING NUTS (3)
3 - FUEL INJECTION PUMP
4 - CASCADE OVERFLOW VALVE
Fig. 28 FILTER HOUSING (EARLY)
1 - FILTER HOUSING
2 - FUEL HEATER AND THERMOSTAT
3 - FUEL HEATER MOUNTING SCREWS
4 - FUEL HEATER ELEC. CONNECTOR
5 - DRAIN VALVE
6 - DRAIN VALVE MOUNTING SCREWS
7 - DRAIN HOSE
8 - WIF SENSOR
9 - WIF SENSOR ELEC. CONNECTOR
DRFUEL DELIVERY - DIESEL 14 - 77
FUEL TRANSFER PUMP (Continued)