fuel type DODGE RAM 2001 Service Service Manual

(3) Clean fitting of any foreign material before dis-
assembly.
(4)Single-Tab Type Fitting:This type of fitting
is equipped with a single pull tab (Fig. 41). The tab
is removable. After tab is removed, quick-connect fit-
ting can be separated from fuel system component.
(a) Press release tab on side of fitting to release
pull tab (Fig. 42).If release tab is not pressed
prior to releasing pull tab, pull tab will be
damaged.
(b) While pressing release tab on side of fitting,
use screwdriver to pry up pull tab (Fig. 42).
(c) Raise pull tab until it separates from quick-
connect fitting (Fig. 43).
(5)Two-Tab Type Fitting:This type of fitting is
equipped with tabs located on both sides of fitting
(Fig. 44). The tabs are supplied for disconnecting
quick-connect fitting from component being serviced.
(a) To disconnect quick-connect fitting, squeeze
plastic retainer tabs (Fig. 44) against sides of
quick-connect fitting with your fingers. Tool use is
not required for removal and may damage plastic
retainer.
(b) Pull fitting from fuel system component
being serviced.
(c) The plastic retainer will remain on compo-
nent being serviced after fitting is disconnected.
The o-rings and spacer will remain in quick-con-
nect fitting connector body.
(6)Plastic Retainer Ring Type Fitting:This
type of fitting can be identified by the use of a full-
round plastic retainer ring (Fig. 45) usually black in
color.(a) To release fuel system component from quick-
connect fitting, firmly push fitting towards compo-
nent being serviced while firmly pushing plastic
retainer ring into fitting (Fig. 45). With plastic ring
depressed, pull fitting from component.The plas-
tic retainer ring must be pressed squarely
into fitting body. If this retainer is cocked
during removal, it may be difficult to discon-
nect fitting. Use an open-end wrench on
shoulder of plastic retainer ring to aid in dis-
connection.
(b) After disconnection, plastic retainer ring will
remain with quick-connect fitting connector body.
Fig. 41 Single-Tab Type Fitting
1 - PULL TAB
2 - QUICK-CONNECT FITTING
3 - PRESS HERE TO REMOVE PULL TAB
4 - INSERTED TUBE END
Fig. 42 Disconnecting Single-Tab Type Fitting
1 - PULL TAB
2 - SCREWDRIVER
3 - QUICK-CONNECT FITTING
Fig. 43 Removing Pull Tab
1 - FUEL TUBE OR FUEL SYSTEM COMPONENT
2 - PULL TAB
3 - QUICK-CONNECT FITTING
4 - FUEL TUBE STOP
BR/BEFUEL DELIVERY - GASOLINE 14 - 23
QUICK CONNECT FITTING (Continued)

(c) Inspect fitting connector body, plastic retainer
ring and fuel system component for damage.
Replace as necessary.(7)Latch Clips:Depending on vehicle model and
engine, 2 different types of safety latch clips are used
(Fig. 46) or (Fig. 47). Type-1 is tethered to fuel line
and type-2 is not. A special tool will be necessary to
disconnect fuel line after latch clip is removed. The
latch clip may be used on certain fuel line/fuel rail
connection, or to join fuel lines together.
(a) Type 1: Pry up on latch clip with a screw-
driver (Fig. 46).
Fig. 44 Typical Two-Tab Type Quick-Connect Fitting
1 - TAB(S)
2 - QUICK-CONNECT FITTING
Fig. 45 Plastic Retainer Ring Type Fitting
1 - FUEL TUBE
2 - QUICK CONNECT FITTING
3 - PUSH
4 - PLASTIC RETAINER
5 - PUSH
6 - PUSH
7 - PUSH
8 - PUSH
Fig. 46 Latch ClipÐType 1
1 - TETHER STRAP
2 - FUEL LINE
3 - SCREWDRIVER
4 - LATCH CLIP
5 - FUEL RAIL
Fig. 47 Latch ClipÐType 2
1 - LATCH CLIP
14 - 24 FUEL DELIVERY - GASOLINEBR/BE
QUICK CONNECT FITTING (Continued)

(b) Type 2: Separate and unlatch 2 small arms
on end of clip (Fig. 47) and swing away from fuel
line.
(c) Slide latch clip toward fuel rail while lifting
with screwdriver.
(d) Insert special fuel line removal tool (Snap-On
number FIH 9055-1 or equivalent) into fuel line
(Fig. 48). Use tool to release locking fingers in end
of line.
(e) With special tool still inserted, pull fuel line
from fuel rail.
(f) After disconnection, locking fingers will
remain within quick-connect fitting at end of fuel
line.
(8) Disconnect quick-connect fitting from fuel sys-
tem component being serviced.
CONNECTING
(1) Inspect quick-connect fitting body and fuel sys-
tem component for damage. Replace as necessary.
(2) Prior to connecting quick-connect fitting to
component being serviced, check condition of fitting
and component. Clean parts with a lint-free cloth.
Lubricate with clean engine oil.
(3) Insert quick-connect fitting into fuel tube or
fuel system component until built-on stop on fuel
tube or component rests against back of fitting.
(4) Continue pushing until a click is felt.
(5) Single-tab type fitting: Push new tab down
until it locks into place in quick-connect fitting.
(6) Verify a locked condition by firmly pulling on
fuel tube and fitting (15-30 lbs.).(7) Latch Clip Equipped: Install latch clip (snaps
into position).If latch clip will not fit, this indi-
cates fuel line is not properly installed to fuel
rail (or other fuel line). Recheck fuel line con-
nection.
(8) Connect negative cable to battery.
(9) Start engine and check for leaks.
ROLLOVER VALVE
DESCRIPTION
Diesel Powered Engine:One rollover valve is
used. The rollover valve is located on the top of the
fuel tank module (Fig. 49). The valve may be serviced
separately.
Gasoline Powered Engines:If equipped with a
26 or 34 gallon fuel tank, two rollover valves are
used. One of the valves is permanently mounted to
the top of fuel tank (Fig. 50). If replacement of this
particular valve is necessary, the fuel tank must be
replaced. The other rollover valve is located on the
top of the fuel pump module (Fig. 50). This valve
may be serviced separately. If replacement is neces-
sary, refer to the Removal/Installation section of this
group.
If equipped with a 35 gallon fuel tank, two rollover
valves are used. Both valves are permanently
mounted to the top of fuel tank (Fig. 51). If replace-
ment is necessary, the fuel tank must be replaced.
Fig. 48 Fuel Line Disconnection Using Special Tool
1 - SPECIAL FUEL LINE TOOL
2 - FUEL LINE
3 - FUEL RAIL
Fig. 49 Rollover Valve LocationÐDiesel Powered
1 - AUXILIARY CAPPED FITTING
2 - FUEL PUMP MODULE
3 - FUEL SUPPLY/RETURN FITTINGS
4 - ELECTRICAL CONNECTOR
5 - LOCKNUT
6 - ROLLOVER VALVE
BR/BEFUEL DELIVERY - GASOLINE 14 - 25
QUICK CONNECT FITTING (Continued)

on preprogrammed (fixed) values and inputs from
other sensors.
Upstream Sensors:Two upstream sensors are
used (1/1 and 2/1). The 1/1 sensor is the first sensor
to receive exhaust gases from the #1 cylinder. They
provide an input voltage to the PCM. The input tells
the PCM the oxygen content of the exhaust gas. The
PCM uses this information to fine tune fuel delivery
to maintain the correct oxygen content at the down-
stream oxygen sensors. The PCM will change the air/
fuel ratio until the upstream sensors input a voltage
that the PCM has determined will make the down-
stream sensors output (oxygen content) correct.
The upstream oxygen sensors also provide an input
to determine mini-catalyst efficiency. Main catalytic
convertor efficiency is not calculated with this pack-
age.
Downstream Sensors:Two downstream sensors
are used (1/2 and 2/2). The downstream sensors are
used to determine the correct air-fuel ratio. As the
oxygen content changes at the downstream sensor,
the PCM calculates how much air-fuel ratio change is
required. The PCM then looks at the upstream oxy-
gen sensor voltage, and changes fuel delivery until
the upstream sensor voltage changes enough to cor-
rect the downstream sensor voltage (oxygen content).
The downstream oxygen sensors also provide an
input to determine mini-catalyst efficiency. Main cat-
alytic convertor efficiency is not calculated with this
package.
Medium and Heavy Duty 8.0L V-10 Engine:
Four oxygen sensors are used (2 upstream, 1 pre-cat-
alyst and 1 post-catalyst). The upstream sensors (1/1
and 2/1) will fine-tune the air-fuel ratio through the
Powertrain Control Module (PCM). The pre-catalyst
(1/2) and post-catalyst (1/3) sensors will determine
catalytic convertor efficiency (efficiency of the main
catalytic convertor). This is also done through the
PCM.
Heavy Duty 5.9L Engine:Downstream sensors
are not used with this emissions package, meaning
catalytic convertor efficiency is not calculated with
this package. Two upstream sensors are used. The
left upstream sensor (1/1) will monitor cylinders 1, 3,
5 and 7. The right upstream sensor (2/1) will monitor
cylinders 2, 4, 6 and 8. The PCM monitors the oxy-
gen content of the sensors, and will fine-tune the air-
fuel ratio.
Engines equipped with either a downstream sen-
sor(s), or a post-catalytic sensor, will monitor cata-
lytic convertor efficiency. If efficiency is below
emission standards, the Malfunction Indicator Lamp
(MIL) will be illuminated and a Diagnostic Trouble
Code (DTC) will be set. Refer to Monitored Systems
in Emission Control Systems for additional informa-
tion.REMOVAL
Never apply any type of grease to the oxygen
sensor electrical connector, or attempt any sol-
dering of the sensor wiring harness. For sensor
operation, it must have a comparison source of
oxygen from outside the exhaust system. This
fresh air is supplied to the sensor through its
pigtail wiring harness.
The O2S (oxygen sensors) are numbered 1/1, 1/2,
1/3, 2/1 and 2/2.
On HDC engines, the pre-catalyst/post catalyst
O2S sensors are located at the inlet and outlet ends
of the catalytic converter (Fig. 39).
The 1/1 and 2/1 sensors are located before the
mini-cats (Fig. 40). The 1/2 and 2/2 sensors are
located after the mini-cats (Fig. 40).
Fig. 39 Pre-catalyst/Post catalyst Oxygen SensorsÐ
HDC Engines
1 - POST CATALYST OXYGEN SENSOR (1/3)
2 - PRE-CATALYST OXYGEN SENSOR (1/2)
Fig. 40 Oxygen SensorsÐ5.2L/5.9L California
Engines
BR/BEFUEL INJECTION - GASOLINE 14 - 47
O2 SENSOR (Continued)

DESCRIPTIONÐFUEL PUMP 235 H.P.
The fuel injection pump is mounted to the rear of
the timing gear housing on the left side of engine
(Fig. 15).
OPERATION
The Bosch VP44 fuel injection pump (Fig. 16) is a
solenoid-valve controlled-radial-piston-distributor
type pump.
The injection pump is driven by the engine cam-
shaft. A gear on the end of the pump shaft meshes
with the camshaft gear. The pump is timed to the
engine. The VP44 is controlled by an integral (and
non-serviceable) Fuel Pump Control Module (FPCM)
(Fig. 15). The FPCM can operate the engine as an
engine controller if a Crankshaft Position Sensor
(CKP) signal is not present.
Fuel from the transfer (lift) pump enters the VP44
where it is pressurized and then distributed through
high-pressure lines to the fuel injectors. The VP44 is
cooled by the fuel that flows through it. A greater
quantity of fuel is required for cooling the VP44 than
what is necessary for engine operation. Because of
this, approximately 70 percent of fuel entering the
pump is returned to the fuel tank through the over-
flow valve and fuel return line. Refer to Overflow
Valve Description/Operation for additional informa-
tion.The VP44 is not self-priming. At least two fuel
injectors must be bled to remove air from the system.
When servicing the fuel system, disconnecting compo-
nents up to the pump will usually not require air
bleeding from the fuel system. However, removal of
the high-pressure lines, removal of the VP44 pump,
or allowing the vehicle to completely run out of fuel,
will require bleeding air from the high-pressure lines
at the fuel injectors.
VP44 timing is matched to engine timing by an off-
set keyway that fits into the pump shaft. This key-
way has a stamped number on it that is matched to
a number on the VP44 pump (each keyway is cali-
brated to each pump).
When removing/installing the VP44, the same
numbered keyway must always be installed.
Also, the arrow on the top of the keyway should
be installed pointed rearward towards the
pump.
Because of electrical control, the injection pump
high and low idle speeds are not adjustable. Also,
adjustment of fuel pump timing is not required and
is not necessary.
DIAGNOSIS AND TESTINGÐFUEL INJECTION
PUMP TIMING
With the Bosch VP44 injection pump, there are no
mechanical adjustments needed for fuel injection tim-
ing. All timing and fuel adjustments are made by the
Engine Control Module (ECM). However, if a Diag-
nostic Trouble Code (DTC) has been stored indicating
an ªengine sync errorº or a ªstatic timing errorº, per-
form the following.
Fig. 15 Fuel Injection Pump Location
1 - FPCM ELECTRICAL CONNECTOR
2 - HIGH-PRESSURE FUEL LINES
3 - FITTINGS
4 - FUEL INJECTION PUMP
5 - FPCM
Fig. 16 Bosch VP44 Fuel Injection Pump
1 - BOSCH VP44 PUMP
14 - 66 FUEL DELIVERY - DIESELBR/BE
FUEL INJECTION PUMP (Continued)

(1) Remove hose clamp and crankcase vent hose at
crankcase breather (Fig. 17). Remove crankcase
breather from gear cover. Breather threads into
cover.
(2) Remove injection pump nut and washer (Fig.
18). Locate keyway behind washer.
(3) Be sure keyway aligning fuel injection pump
shaft to injection pump gear is in proper position and
pump gear has not slipped on pump shaft.
The following steps will require removing timing
gear cover to gain access to timing gears. Refer to
Group 9, Engines for procedures.
(4) Use a T-type puller to separate injection pump
gear from pump shaft.
(5) Be sure keyway has been installed with arrow
pointed torearof pump (Fig. 19).
(6)Pump timing has been calibrated to pump
keyway. Be sure 3±digit number on pump key-
way (Fig. 19) matches 3±digit number on fuel
injection pump data plate. Plate is located on
side of injection pump (Fig. 20). Twenty±one dif-
ferent calibrated keyways/pumps are available.
(7) Verify timing marks on crank, cam and pump
are aligned (Fig. 21).
(8) Perform necessary gear alignment/repairs as
needed.
(9) Install crankcase breather to gear cover. Install
hose clamp and crankcase vent hose to breather (Fig.
17).
(10) After repairs are completed, erase DTC using
DRB Scan Tool.
REMOVAL
CAUTION: Refer to Cleaning Fuel System Parts.
(1) Disconnect both negative battery cables at both
batteries. Cover and isolate ends of cables.
(2) Thoroughly clean fuel lines at cylinder head
and injection pump ends. Thoroughly clean fuel injec-
tion pump and supply/return lines at side of pump.
(3) Disconnect 9±way electrical connector at Fuel
Pump Control Module (FPCM) (Fig. 22).
(4) Remove fuel return line at side of injection
pump by removing overflow valve (Fig. 23). Place rag
beneath overflow valve to catch excess fuel.
(5) Remove fuel supply line at side of injection
pump by removing banjo bolt (Fig. 23). Also remove
same line at top of fuel filter housing (banjo bolt).
(6) Remove all high-pressure fuel lines, intake air
tube, accelerator pedal position sensor, air intake
housing, engine oil dipstick tube, wiring clips, electri-
cal cables at intake heaters and engine lifting
bracket. Refer to High-Pressure Fuel Line Removal/
Installation. All of these items are covered in this
procedure.
(7) Remove hose clamp at crankcase vent hose
(Fig. 24) and remove hose from canister.
(8) Remove (unscrew) canister (Fig. 24) from gear
cover.
Fig. 21 Checking Fuel Injection Pump Gear Timing
1 - PUMP SHAFT
2 - KEYWAY
3 - PUMP GEAR
4 - CAM GEAR
5 - CRANKSHAFT GEAR
Fig. 22 FPCM 9±Way Connector
1 - FPCM ELECTRICAL CONNECTOR
2 - HIGH-PRESSURE FUEL LINES
3 - FITTINGS
4 - FUEL INJECTION PUMP
5 - FPCM
14 - 68 FUEL DELIVERY - DIESELBR/BE
FUEL INJECTION PUMP (Continued)

(13) Use T-bar type puller (Fig. 28) to separate
injection pump gear from injection pump shaft.
Attach two M8 X 1.24 MM (metric) screws through
puller and into two threaded holes supplied in pump
gear. Pull injection pump gear forward until it loos-
ens from injection pump shaft.Pull on gear only
enough to loosen it from injection pump shaft.
Pulling gear too far may cause damage or
breakage to gear cover.(14) Remove 2 rear/lower pump bracket bolts (Fig.
29).
(15) Remove 4 injection pump-to-gear housing
mounting nuts (Fig. 30).
(16) Remove injection pump from gear housing.
Take care not to nick injection pump shaft on
aluminum gear housing when removing pump.
Also be very careful not to drop pump keyway
(Fig. 32) into gear housing.
CAUTION: Whenever the fuel injection pump is
removed from the engine, the pump drive gear is lay-
ing loose on the camshaft drive gear. Never attempt
to crank or rotate the engine with the pump removed
from the engine. Serious damage will occur.
INSTALLATION
(1) Inspect pump mounting surfaces at pump and
mounting flange for nicks, cuts or damage. Inspect
o-ring surfaces for nicks, cuts or damage.
(2) Clean injection pump mounting flange (Fig. 31)
at gear housing. Also clean front of injection pump.
(3) Install new rubber o-ring (Fig. 33) at pump
mounting area.
(4) Apply clean engine oilto injection pump
o-ring only.
The machined tapers on both injection pump
shaft and injection pump gear (Fig. 34) must be
absolutely dry, clean and free of any dirt or oil
film. This will ensure proper gear-to-shaft tight-
ening.
Fig. 31 Cleaning Pump Mounting Flange
1 - PUMP MOUNTING FLANGE
Fig. 32 Keyway, Keyway Arrow and Keyway Number
1 - INJECTION PUMP
2 - DIRECTIONAL ARROW
3 - 3±DIGIT KEYWAY NUMBER
4 - O-RING
Fig. 33 Keyway, Keyway Arrow and Keyway Number
1 - INJECTION PUMP
2 - DIRECTIONAL ARROW
3 - 3±DIGIT KEYWAY NUMBER
4 - O-RING
BR/BEFUEL DELIVERY - DIESEL 14 - 71
FUEL INJECTION PUMP (Continued)

(5) Clean pump gear and pump shaft at machined
tapers (Fig. 34) with an evaporative type cleaner
such as brake cleaner.
Keyway Installation:
(6) The pump/gear keyway has an arrow and a
3±digit number stamped at top edge (Fig. 33). Posi-
tion keyway into pump shaft witharrow pointed to
rear of pump.Also be sure 3±digit number stamped
to top of keyway is same as 3±digit number stamped
to injection pump data plate (Fig. 35). If wrong key-
way is installed, a diagnostic trouble code may be
set.
(7) Position pump assembly to mounting flange on
gear cover while aligning injection pump shaft
through back of injection pump gear. When installing
pump, dowel (Fig. 34) on mounting flange must align
to hole in front of pump.
(8) After pump is positioned flat to mounting
flange, install four pump mounting nuts and tighten
finger tight only. Do not attempt a final tightening at
this time.Do not attempt to tighten (pull) pump
to gear cover using mounting nuts. Damage to
pump or gear cover may occur. The pump must
be positioned flat to its mounting flange before
attempting to tighten mounting nuts.
(9) To prevent damage or cracking of components,
tighten nuts/bolts in the following sequence:
(a) Install injection pump shaft washer and nut
to pump shaft. Tighten nutfinger tight only.
(b) Install 2 rear/lower pump mounting bolts
finger tight only.(c) Do preliminary tightening of injection pump
shaft nut to 30 N´m (15±22 ft. lbs.) torque.This is
not the final torque.
(d) Tighten 4 pump mounting nuts to 43 N´m
(32 ft. lbs.) torque.
(e) Tighten 2 rear/lower pump bracket-to-pump
bolts 24 N´m (18 ft. lbs.) torque.
(f) Do final tightening of injection pump shaft
nut to 170 N´m (125 ft. lbs.) torque. Use barring
tool to prevent engine from rotating when tighten-
ing gear.
(10) Install canister (Fig. 24) to gear cover.
(11) Install crankcase vent hose (Fig. 24) to canis-
ter and install hose clamp.
(12) Using new gaskets, install fuel return line
and overflow valve to side of injection pump (Fig. 23).
Tighten overflow valve to 24 N´m (18 ft. lbs.) torque.
(13)
Using new gaskets, install fuel supply line to
side of injection pump and top of fuel filter housing (Fig.
23). Tighten banjo bolts to 24 N´m (18 ft. lbs.) torque.
(14)Install all high-pressure fuel lines, intake air
tube, accelerator pedal position sensor, air intake hous-
ing, engine oil dipstick tube, wiring clips, electrical
cables at intake heaters and engine lifting bracket.
Refer to High-Pressure Fuel Line Removal/Installation.
All of these items are covered in this procedure.
Fig. 34 Injection Pump Installation
1 - DOWEL
2 - PUMP
3 - PUMP SHAFT TAPER
4 - INJECTION PUMP GEAR TAPER
Fig. 35 Injection Pump Data Plate Location
1 - PUMP DATA PLATE
14 - 72 FUEL DELIVERY - DIESELBR/BE
FUEL INJECTION PUMP (Continued)

(3) The plastic fuel tank module locknut is
threaded onto fuel tank (Fig. 39). Install Special Tool
6856 to locknut and remove locknut (Fig. 49). 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 arrow at top of module should be aligned
between two marks stamped into tank (approximate-
ly 2 o'clock position). The fuel line connectors, roll
over valve and fuel gauge electrical connector should
all be pointed to drivers side of vehicle. Rotate and
align module/tank marks 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 located
on the left-rear side of the engine cylinder block
above the starter motor (Fig. 50). The 12±volt electric
vane-type pump is operated and controlled by the
Engine Control Module (ECM) (Fig. 51).
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.
Normal current flow to the pump is 12 amperes.
With the engine running, the pump has2modes of
operation: Mode 1: 100 percent duty-cycle with a
minimum pressure of 10 psiexcept when the
engine is cranking.Mode 2: 25 percent duty-cycle
with minimum pressure of 7 psiwith the engine
cranking
The 25 percent duty-cycle is used to limit injection
pump inlet pressure until the engine is running.
Fig. 48 Top View of Fuel Tank ModuleÐDiesel
1 - AUXILIARY CAPPED FITTING
2 - FUEL PUMP MODULE
3 - FUEL SUPPLY/RETURN FITTINGS
4 - ELECTRICAL CONNECTOR
5 - LOCKNUT
6 - ROLLOVER VALVE
Fig. 49 Locknut Removal/InstallationÐTYPICAL
MODULE
1 - SPECIAL TOOL 6856
2 - LOCKNUT
BR/BEFUEL DELIVERY - DIESEL 14 - 79
FUEL TANK MODULE (Continued)

OPERATION
High-pressure fuel is supplied from the injection
pump, through a high-pressure fuel line, through a
steel connector and into the fuel injector. When fuel
pressure rises to approximately 31,026 kPa (4,500
psi), the needle valve spring tension is overcome. The
needle valve rises and fuel flows through the spray
holes in the nozzle tip into the combustion chamber.
The pressure required to lift the needle valve is the
nozzle opening pressure. This is sometimes referred
to as the ªpopº pressure setting.
Each fuel injector is connected to each high-pres-
sure fuel line with a steel connector (Fig. 11). This
steel connector is positioned into the cylinder head
and sealed with an o-ring. The connectors are sealed
to the high-pressure fuel lines with fittings (Fig. 11).
The ferrule (Fig. 11) on the end of the high-pressure
fuel line pushes against the steel connector when the
fuel line fitting is torqued into the cylinder head.
This torquing force provides a sealing pressure
between both the fuel line-to-connector and the fuel
connector-to-fuel injector.The fitting torque is
very critical.If the fitting is under torqued, the
mating surfaces will not seal and a high-pressure
fuel leak will result. If the fitting is over torqued, the
connector and injector will deform and also cause a
high-pressure fuel leak. This leak will be inside the
cylinder head and will not be visible. The result will
be a possible fuel injector miss-fire and low power.
The fuel injectors use hole type nozzles (Fig. 12).
High-pressure flows into the side of the injector and
causes the injector needle to lift and fuel to be
injected. The clearances in the nozzle bore (Fig. 12)
are extremely small and any sort of dirt or contami-
nants will cause the injector to stick. Because of this,
it is very important to do a thorough cleaning of any
lines before opening up any fuel system component.
Fig. 11 Fuel Injector Connections
1 - CONNECTOR
2 - O-RING
3 - FERRULE
4 - FITTING
5 - FUEL LINE
6 - INJECTOR
Fig. 12 Fuel Injector Spray Pattern
1 - INJECTOR
2 - CLEARANCE
3 - SHIM
4 - NOZZLE
Fig. 13 Fuel Injector Edge Filter
1 - EDGE FILTER
2 - FITTING
3 - FUEL INJECTOR
14 - 94 FUEL INJECTION - DIESELBR/BE
FUEL INJECTOR (Continued)