ad blue DODGE RAM 2001 Service Owner's Manual

MANIFOLD ABSOLUTE PRESSURE SENSOR (8.0L)-3WAY
CAV CIRCUIT FUNCTION
1 K6 20VT/WT 5V SUPPLY
2 K4 20BK/LB SENSOR GROUND
3 K1 18DG/RD MAP SENSOR SIGNAL
MANIFOLD AIR PRESSURE SENSOR (DIESEL)-3WAY
CAV CIRCUIT FUNCTION
A K7 18OR 5V SUPPLY
B K104 18BK/LB SENSOR GROUND
C G12 18GY/RD MANIFOLD AIR PRESSURE SENSOR SIGNAL
MULTI-FUNCTION SWITCH - 24 WAY
CAV CIRCUIT FUNCTION
1 V9 16WT/DB WIPER SWITCH MODE SIGNAL
2 V8 16VT WIPER SWITCH MODE SENSE
3 V10 16BR WASHER SWITCH SENSE
4 V6 16DB FUSED IGNITION SWITCH OUTPUT (RUN-ACC)
5 V4 16RD/YL WIPER SWITCH HIGH SPEED OUTPUT
6 V3 16BR/WT LOW SPEED WIPER SWITCH OUTPUT
7 V49 16RD/BK DRIVER LOW SPEED WIPER MOTOR DRIVER
8 V49 16RD/BK DRIVER LOW SPEED WIPER MOTOR DRIVER
9 V3 16BR/WT LOW SPEED WIPER SWITCH OUTPUT
10 - -
11 L60 18TN RIGHT TURN SIGNAL
12 L62 16BR/RD RIGHT TURN SIGNAL
13 L19 16PK HAZARD FLASHER SIGNAL
14 L50 16WT/TN BRAKE LAMP SWITCH OUTPUT
15 L63 16DG/RD LEFT TURN SIGNAL
16 L61 18LG LEFT TURN SIGNAL
17 L6 16RD/GY FLASHER OUTPUT
18 L4 18VT/WT DIMMER SWITCH LOW BEAM OUTPUT
19 L2 18LG HEADLAMP SWITCH OUTPUT
20 L3 14RD/OR DIMMER SWITCH HIGH BEAM OUTPUT
21 Z3 16BK/OR GROUND
22 - -
23 - -
24 - -
OUTPUT SPEED SENSOR - DK. BLUE 2 WAY
CAV CIRCUIT FUNCTION
1 T14 18LG/BK OUTPUT SPEED SENSOR SIGNAL
2 T13 18DB/BK OUTPUT SPEED SENSOR GROUND
BR/BE8W-80 CONNECTOR PIN-OUTS 8W - 80 - 59

PASSENGER DOOR WINDOW/LOCK SWITCH - 11 WAY
CAV CIRCUIT FUNCTION
1 Q16 14BR/WT MASTER WINDOW SWITCH RIGHT FRONT (UP)
2 Q26 14VT/WT MASTER WINDOW SWITCH RIGHT FRONT (DOWN)
3 Q22 14VT RIGHT FRONT WINDOW DRIVER (DOWN)
4 Q12 14BR RF WINDOW DRIVER (UP)
5 F35 18RD FUSED B(+)
6 P35 18OR/VT DOOR LOCK SWITCH CONTROL
7 P30 18OR/DG PASSENGER DOOR LOCK SWITCH OUTPUT
8 Z2 14BK/LG GROUND
9 P31 18PK/DG PASSENGER DOOR UNLOCK SWITCH OUTPUT
10 P36 18PK/VT DOOR UNLOCK SWITCH CONTROL
11 F21 14TN FUSED IGNITION SWITCH OUTPUT (RUN)
PASSENGER HEATED SEAT CUSHION-4WAY
CAV CIRCUIT FUNCTION
1 P130 16TN RIGHT SEAT HEATER B(+) DRIVER
2 Z2 18BK/LG GROUND
3 P144 20BK/WT SEAT TEMPERATURE 5V SUPPLY
4 P142 20DB RIGHT SEAT TEMPERATURE SENSOR INPUT
PASSENGER HEATED SEAT SWITCH - BLUE 6 WAY
CAV CIRCUIT FUNCTION
1 P138 20VT/LG RIGHT SEAT LOW HEAT LED DRIVER
2 E2 22OR PANEL LAMPS FEED
3 Z3 20BK/OR GROUND
4 F15 20DB FUSED IGNITION SWITCH OUTPUT (RUN)
5 P140 20VT/BK RIGHT SEAT HIGH HEAT LED DRIVER
6 P8 20LB/WT PASSENGER HEATED SEAT SWITCH
PASSENGER LUMBAR MOTOR-2WAY
CAV CIRCUIT FUNCTION
1 P106 16DG/WT LUMBAR MOTOR FORWARD
2 P107 16OR/BK LUMBAR MOTOR REARWARD
PASSENGER POWER SEAT FRONT VERTICAL MOTOR (CLUB CAB)-2WAY
CAV CIRCUIT FUNCTION
A P20 16RD/LG RIGHT SEAT FRONT DOWN
B P18 16YL/LG RIGHT SEAT FRONT UP
8W - 80 - 64 8W-80 CONNECTOR PIN-OUTSBR/BE

(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-
ing stones. A true and complete surface must be
obtained.
(2) Measure the concentricity of valve seat using a
dial indicator. Total runout should not exceed 0.051
mm (0.002 in.) total indicator reading.
(3) Inspect the valve seat with Prussian blue, to
determine where the valve contacts the seat. To do
this, coat valve seat LIGHTLY with Prussian blue
then set valve in place. Rotate the valve with light
pressure. If the blue is transferred to the center of
valve face, contact is satisfactory. If the blue is trans-
ferred to the top edge of valve face, lower valve seat
with a 15É stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60É stone.
(4) When seat is properly positioned the width of
intake seats should be 1.016-1.524 mm (0.040-0.060
in.). The width of the exhaust seats should be 1.524-
2.032 mm (0.060-0.080 in.).
VALVE SPRINGS
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested. As an example the compression length of
the spring to be tested is 1-5/16 in.. Turn table of
Universal Valve Spring Tester Tool until surface is in
line with the 1-5/16 in. mark on the threaded stud.
Be sure the zero mark is to the front (Fig. 14). Place
spring over stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until
ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by 2. This will give the
spring load at test length. Fractional measurements
are indicated on the table for finer adjustments.
Refer to specifications to obtain specified height and
allowable tensions. Discard the springs that do not
meet specifications.
REMOVAL
(1) Remove the cylinder head (Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(2) Compress valve springs using Valve Spring
Compressor Tool MD- 998772A and adapter 6716A.
(3) Remove valve retaining locks, valve spring
retainers, valve stem seals and valve springs.
(4) Before removing valves, remove any burrs from
valve stem lock grooves to prevent damage to the
valve guides. Identify valves to ensure installation in
original location.
CLEANING
Clean valves thoroughly. Discard burned, warped,
or cracked valves.
Remove carbon and varnish deposits from inside of
valve guides with a reliable guide cleaner.
INSPECTION
Measure valve stems for wear. If wear exceeds
0.051 mm (0.002 in.), replace the valve.
Measure valve stem guide clearance as follows:
(1) Install Valve Guide Sleeve Tool C-3973 over
valve stem and install valve (Fig. 15). The special
sleeve places the valve at the correct height for
checking with a dial indicator.
(2) Attach dial indicator Tool C-3339 to cylinder
head and set it at right angles to valve stem being
measured (Fig. 16).
(3) Move valve to and from the indicator. The total
dial indicator reading should not exceed 0.432 mm
(0.017 in.). Ream the guides for valves with oversize
stems if dial indicator reading is excessive or if the
stems are scuffed or scored.
Fig. 14 Testing Valve Spring for Compressed
Length
1 - TORQUE WRENCH
2 - VALVE SPRING TESTER
Fig. 15 Positioning Valve with Tool C-3973
1 - VALVE
2 - SPACER TOOL
BR/BEENGINE 3.9L 9 - 27
INTAKE/EXHAUST VALVES & SEATS (Continued)

(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-
ing stones. A true and complete surface must be
obtained.
(2) Measure the concentricity of valve seat using a
dial indicator. Total runout should not exceed 0.051
mm (0.002 in.) total indicator reading.
(3) Inspect the valve seat with Prussian blue, to
determine where the valve contacts the seat. To do
this, coat valve seat LIGHTLY with Prussian blue
then set valve in place. Rotate the valve with light
pressure. If the blue is transferred to the center of
valve face, contact is satisfactory. If the blue is trans-
ferred to the top edge of valve face, lower valve seat
with a 15É stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60É stone.
(4) When seat is properly positioned the width of
intake seats should be 1.016-1.524 mm (0.040-0.060
in.). The width of the exhaust seats should be 1.524-
2.032 mm (0.060-0.080 in.).
VALVE SPRINGS
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested. As an example the compression length of
the spring to be tested is 1-5/16 in.. Turn table of
Universal Valve Spring Tester Tool until surface is in
line with the 1-5/16 in. mark on the threaded stud.
Be sure the zero mark is to the front (Fig. 13). Place
spring over stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until
ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by 2. This will give the
spring load at test length. Fractional measurements
are indicated on the table for finer adjustments.
Refer to specifications to obtain specified height and
allowable tensions. Discard the springs that do not
meet specifications.
REMOVAL
(1) Remove the cylinder head (Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(2) Compress valve springs using Valve Spring
Compressor Tool MD- 998772A and adapter 6716A.
(3) Remove valve retaining locks, valve spring
retainers, valve stem seals and valve springs.
(4) Before removing valves, remove any burrs from
valve stem lock grooves to prevent damage to the
valve guides. Identify valves to ensure installation in
original location.
CLEANING
Clean valves thoroughly. Discard burned, warped,
or cracked valves.
Remove carbon and varnish deposits from inside of
valve guides with a reliable guide cleaner.
INSPECTION
Measure valve stems for wear. If wear exceeds
0.051 mm (0.002 in.), replace the valve.
Measure valve stem guide clearance as follows:
(1) Install Valve Guide Sleeve Tool C-3973 over
valve stem and install valve (Fig. 14). The special
sleeve places the valve at the correct height for
checking with a dial indicator.
(2) Attach dial indicator Tool C-3339 to cylinder
head and set it at right angles to valve stem being
measured (Fig. 15).
(3) Move valve to and from the indicator. The total
dial indicator reading should not exceed 0.432 mm
(0.017 in.). Ream the guides for valves with oversize
stems if dial indicator reading is excessive or if the
stems are scuffed or scored.
Fig. 13 Testing Valve Spring for Compressed
Length
1 - TORQUE WRENCH
2 - VALVE SPRING TESTER
Fig. 14 Positioning Valve with Tool C-3973
1 - VALVE
2 - SPACER TOOL
9 - 84 ENGINE 5.2LBR/BE
INTAKE/EXHAUST VALVES & SEATS (Continued)

VALVES
Inspect the remaining margin after the valves are
refaced (Fig. 11). Valves with less than 1.190 mm
(0.047 in.) margin should be discarded.
VALVE SEATS
CAUTION: DO NOT un-shroud valves during valve
seat refacing (Fig. 12).(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-
ing stones. A true and complete surface must be
obtained.
(2) Measure the concentricity of valve seat using a
dial indicator. Total runout should not exceed 0.051
mm (0.002 in.) total indicator reading.
(3) Inspect the valve seat with Prussian blue, to
determine where the valve contacts the seat. To do
this, coat valve seat LIGHTLY with Prussian blue
then set valve in place. Rotate the valve with light
pressure. If the blue is transferred to the center of
valve face, contact is satisfactory. If the blue is trans-
ferred to the top edge of valve face, lower valve seat
with a 15É stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60É stone.
(4) When seat is properly positioned the width of
intake seats should be 1.016-1.524 mm (0.040-0.060
in.). The width of the exhaust seats should be 1.524-
2.032 mm (0.060-0.080 in.).
VALVE SPRINGS
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested. As an example the compression length of
the spring to be tested is 1-5/16 in.. Turn table of
Universal Valve Spring Tester Tool until surface is in
line with the 1-5/16 in. mark on the threaded stud.
Be sure the zero mark is to the front (Fig. 13). Place
spring over stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until
ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by 2. This will give the
spring load at test length. Fractional measurements
are indicated on the table for finer adjustments.
Refer to specifications to obtain specified height and
allowable tensions. Discard the springs that do not
meet specifications.
REMOVAL
(1) Remove the cylinder head (Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(2) Compress valve springs using Valve Spring
Compressor Tool MD- 998772A and adapter 6716A.
(3) Remove valve retaining locks, valve spring
retainers, valve stem seals and valve springs.
(4) Before removing valves, remove any burrs from
valve stem lock grooves to prevent damage to the
valve guides. Identify valves to ensure installation in
original location.
CLEANING
Clean valves thoroughly. Discard burned, warped,
or cracked valves.
Remove carbon and varnish deposits from inside of
valve guides with a reliable guide cleaner.
Fig. 11 Intake and Exhaust Valves
1 - MARGIN
2 - VALVE SPRING RETAINER LOCK GROOVE
3 - STEM
4-FACE
Fig. 12 Refacing Valve Seats
1-STONE
2 - PILOT
3 - VALVE SEAT
4 - SHROUD
9 - 140 ENGINE 5.9LBR/BE
INTAKE/EXHAUST VALVES & SEATS (Continued)

(3) Inspect the valve seat with Prussian blue to
determine where the valve contacts the seat. To do
this, coat valve seat LIGHTLY with Prussian blue
then set valve in place. Rotate the valve with light
pressure. If the blue is transferred to the center of
valve face, contact is satisfactory. If the blue is trans-
ferred to the top edge of valve face, lower valve seat
with a 15É stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60É stone.
(4) When seat is properly positioned the width of
valve seats should be 1.016-1.524 mm (0.040-0.060
inch).
VALVE SPRING INSPECTION
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested. As an example the compression length of
the spring to be tested is 1-5/16 inch. Turn table of
Universal Valve Spring Tester Tool until surface is in
line with the 1-5/16 inch mark on the threaded stud.
Be sure the zero mark is to the front (Fig. 19). Place
spring over stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until
ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by 2. This will give the
spring load at test length. Fractional measurements
are indicated on the table for finer adjustments.
Refer to specifications to obtain specified height and
allowable tensions. Discard the springs that do not
meet specifications.
REMOVALÐVALVE STEM SEALS
NOTE: This procedure is done with the cylinder
head installed.
(1) Disconnect the negative cable from the battery.
(2) Set engine basic timing to Top Dead Center
(TDC) and remove air cleaner.
(3) Remove cylinder head covers (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL) and spark plugs (Refer to 8
- ELECTRICAL/IGNITION CONTROL/SPARK
PLUG - REMOVAL).
(4) Using suitable socket and flex handle at crank-
shaft retaining bolt, turn engine so that the piston of
the cylinder to be worked on, is at TDC on the com-
pression stroke.
(5) Remove rocker arms (Refer to 9 - ENGINE/
CYLINDER HEAD/ROCKER ARM / ADJUSTER
ASSY - REMOVAL).
(6) With air hose attached to an adapter installed
in the spark plug hole, apply 620-689 kPa (90-100
psi) air pressure.
(7) Using Valve Spring Compressor Tool
MD-998772A with adapter 6716A (Fig. 20), compress
valve spring and remove retainer valve locks and
valve spring.
(8) Remove the valve stem seal.
REMOVALÐVALVES AND VALVE SPRINGS
(1) Remove the cylinder head (Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(2) Special studs must be used to adapt the Valve
Spring Compressor Tool to the V-10 cylinder head
(Fig. 21). Install the metric end into the Special Tool
MD998772A and the 5/16 end into the cylinder head.
Fig. 18 Intake and Exhaust Valves
1 - MARGIN
2 - VALVE SPRING RETAINER LOCK GROOVE
3 - STEM
4-FACE
Fig. 19 Testing Valve Spring for Compressed
1 - TORQUE WRENCH
2 - VALVE SPRING TESTER
BR/BEENGINE 8.0L 9 - 197
INTAKE/EXHAUST VALVES & SEATS (Continued)

EXCESSIVE WHITE SMOKE
POSSIBLE CAUSE CORRECTION
Fuel injector protrusion not correct. Check washer (shim) at bottom of fuel injector for
correct thickness. (Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/FUEL INJECTOR - INSTALLATION)
Fuel injection pump malfunctioning. A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information.
Fuel supply side restriction to transfer pump. Refer to Fuel Transfer Pump Pressure (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/FUEL TRANSFER
PUMP - DIAGNOSIS AND TESTING)
Fuel transfer (lift) pump malfunctioning. A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information. Also refer to Fuel
Transfer Pump Pressure Testing (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL TRANSFER PUMP -
DIAGNOSIS AND TESTING).
Intake/Exhaust valve adjustments not correct (too tight). (Refer to 9 - ENGINE/CYLINDER HEAD/INTAKE/
EXHAUST VALVES & SEATS - STANDARD
PROCEDURE).
Intake manifold air temperature sensor malfunctioning. A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information.
Intake manifold heater circuit not functioning correctly in
cold weather.A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information. Also check heater
elements for correct operation.
Intake manifold heater elements not functioning
correctly in cold weather.A diagnostic trouble code WILL NOT BE SET if heater
elements are malfunctioning. Refer to NTC tests in
Powertrain Diagnostic Procedures Information.
Internal engine damage (scuffed cylinder). Analyze engine oil and inspect oil filter to locate area of
probable damage.
Restriction in fuel supply side of fuel system. Refer to Fuel Transfer Pump Pressure Testing (Refer to
14 - FUEL SYSTEM/FUEL DELIVERY/FUEL
TRANSFER PUMP - DIAGNOSIS AND TESTING).
Static timing incorrect. A DTC should have been set. If so, (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/FUEL INJECTION
PUMP - DIAGNOSIS AND TESTING).
EXCESSIVE BLUE SMOKE
POSSIBLE CAUSE CORRECTION
Dirty air cleaner or restricted turbocharger intake duct. Check Filter MinderTat air filter housing. (Refer to 9 -
ENGINE/AIR INTAKE SYSTEM/AIR CLEANER
ELEMENT - REMOVAL).
Air leak in boost system between turbocharger
compressor outlet and intake manifold.Service air charge system..
Obstruction in exhaust manifold. Remove exhaust manifold and inspect for blockage
(Refer to 9 - ENGINE/MANIFOLDS/EXHAUST
MANIFOLD - REMOVAL).
Restricted turbocharger drain tube. Remove turbocharger drain tube and remove
obstruction.
Crankcase ventilation system plugged. Inspect crankcase breather and vent tube for sludge
formation or obstructions.
9 - 236 ENGINE 5.9L DIESELBR/BE
ENGINE 5.9L DIESEL (Continued)

EXCESSIVE BLUE SMOKE
POSSIBLE CAUSE CORRECTION
Valve seals are worn, brittle, or improperly installed. Replace valve stem oil seals (Refer to 9 - ENGINE/
CYLINDER HEAD/INTAKE/EXHAUST VALVES &
SEATS - REMOVAL).
Valve stems and/or guides are worn. Remove valves and inspect valves and guides. (Refer
to 9 - ENGINE/CYLINDER HEAD/INTAKE/EXHAUST
VALVES & SEATS - STANDARD PROCEDURE).
Broken or Improperly installed piston rings. Tear down engine and inspect piston rings.
Excessive piston ring end gap. Remove pistons and measure piston ring end gap
(Refer to 9 - ENGINE/ENGINE BLOCK/PISTON RINGS
- STANDARD PROCEDURE).
Excessive cylinder bore wear and taper. Remove pistons and measure cylinder bore wear and
taper (Refer to 9 - ENGINE/ENGINE BLOCK -
STANDARD PROCEDURE).
Cylinder damage. Remove pistons and inspect cylinder bore for cracks or
porosity. Repair with cylinder liner if necessary. (Refer
to 9 - ENGINE/ENGINE BLOCK - STANDARD
PROCEDURE).
Piston damage. Remove pistons and inspect for cracks, holes. Measure
piston for out-of-round and taper (Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON & CONNECTING
ROD - INSPECTION).
Turbocharger failure. (Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER - INSPECTION).
STANDARD PROCEDUREÐFORM-IN-PLACE
GASKETS & SEALERS
There are numerous places where form-in-place
gaskets are used on the engine. Care must be taken
when applying form-in-place gaskets to assure
obtaining the desired results.Do not use form-in-
place gasket material unless specified.Bead size,
continuity, and location are of great importance. Too
thin a bead can result in leakage while too much can
result in spill-over which can break off and obstruct
fluid feed lines. A continuous bead of the proper
width is essential to obtain a leak-free gasket.
There are numerous types of form-in-place gasket
materials that are used in the engine area. Mopart
Engine RTV GEN II, MopartATF-RTV, and Mopart
Gasket Maker gasket materials, each have different
properties and can not be used in place of the other.
MOPARtENGINE RTV GEN II
MopartEngine RTV GEN II is used to seal com-
ponents exposed to engine oil. This material is a spe-
cially designed black silicone rubber RTV that
retains adhesion and sealing properties when
exposed to engine oil. Moisture in the air causes the
material to cure. This material is available in three
ounce tubes and has a shelf life of one year. After one
year this material will not properly cure. Alwaysinspect the package for the expiration date before
use.
MOPARtATF RTV
MopartATF RTV is a specifically designed black
silicone rubber RTV that retains adhesion and seal-
ing properties to seal components exposed to auto-
matic transmission fluid, engine coolants, and
moisture. This material is available in three ounce
tubes and has a shelf life of one year. After one year
this material will not properly cure. Always inspect
the package for the expiration date before use.
MOPARtGASKET MAKER
MopartGasket Maker is an anaerobic type gasket
material. The material cures in the absence of air
when squeezed between two metallic surfaces. It will
not cure if left in the uncovered tube. The anaerobic
material is for use between two machined surfaces.
Do not use on flexible metal flanges.
MOPARtGASKET SEALANT
MopartGasket Sealant is a slow drying, perma-
nently soft sealer. This material is recommended for
sealing threaded fittings and gaskets against leakage
of oil and coolant. Can be used on threaded and
machined parts under all temperatures. This mate-
rial is used on engines with multi-layer steel (MLS)
cylinder head gaskets. This material also will pre-
BR/BEENGINE 5.9L DIESEL 9 - 237
ENGINE 5.9L DIESEL (Continued)

(e) Connect electrical connector to WIF sensor.
(f) Install fuel filter. Refer to previous steps.
(4)Fuel Heater Element:
(a) Do not install fuel filter until heater element
is installed.
(b) Position heater element into filter housing
(fingers downward). Lock fingers into housing.
(c) Install new o-ring to electrical connector
(where connector passes through filter housing).
Apply a light film of clean diesel oil to o-ring seal.
Press this connector into filter housing until it
snaps into heater element.
(d) Install temperature sensor housing and 2
mounting screws to fuel filter housing.
(e) Connect electrical connector.
(f) Install fuel filter. Refer to previous steps.
(5)Drain Valve:
(a) Install 2 new o-rings to valve and filter hous-
ing.
(b) Apply a light film of clean diesel oil to both
seals.
(c) Position valve to filter housing.
(d) Install 4 mounting screws and tighten to 3±5
N´m (30±40 in. lbs.) torque.
(e) Connect drain hose to drain valve.
(f) Install fuel filter. Refer to previous steps.
(6) Start engine and check for leaks.
FUEL HEATER
DESCRIPTION
The fuel heater assembly is located on the side of
the fuel filter housing (Fig. 9).
The heater/element assembly is equipped with a
temperature sensor (thermostat) that senses fuel
temperature. This sensor is attached to the fuel heat-
er/element assembly.
OPERATION
The fuel heater is used to prevent diesel fuel from
waxing during cold weather operation.
When the temperature is below 4568 degrees F,
the temperature sensor allows current to flow to the
heater element warming the fuel. When the temper-
ature is above 7568 degrees F, the sensor stops cur-
rent flow to the heater element.
Battery voltage to operate the fuel heater element
is supplied from the ignition switch and through the
fuel heater relay. Also refer to Fuel Heater Relay.
The fuel heater element and fuel heater relay
are not computer controlled.
The heater element operates on 12 volts, 300 watts
at 0 degrees F.
DIAGNOSIS AND TESTING - FUEL HEATER
The fuel heater is used to prevent diesel fuel from
waxing during cold weather operation.
NOTE: The fuel heater element, fuel heater relay
and fuel heater temperature sensor are not con-
trolled by the Powertrain Control Module (PCM).
A malfunctioning fuel heater can cause a wax
build-up in the fuel filter/water separator. Wax
build-up in the filter/separator can cause engine
starting problems and prevent the engine from rev-
ving up. It can also cause blue or white fog-like
exhaust. If the heater is not operating in cold tem-
peratures, the engine may not operate due to fuel
waxing.
The fuel heater assembly is located on the side of
the fuel filter housing (Fig. 10).
The heater assembly is equipped with a built-in
fuel temperature sensor (thermostat) that senses fuel
temperature. When fuel temperature drops below 45
degrees68 degrees F, the sensor allows current to
flow to the built-in heater element to warm the fuel.
When fuel temperature rises above 75 degrees68
degrees F, the sensor stops current flow to the heater
element (circuit is open).
Fig. 9 Fuel Heater Location
1 - FUEL HEATER AND TEMP. SENSOR
2 - FUEL FILTER/WATER SEPARATOR
3 - FUEL HEATER ELECTRICAL CONNECTOR
14 - 62 FUEL DELIVERY - DIESELBR/BE
FUEL FILTER / WATER SEPARATOR (Continued)

(3) Once injector has been found to be malfunc-
tioning, remove it from engine and test it. Refer to
Fuel Injector Removal/Installation.
WARNING: FUEL INJECTOR TESTERS CAN
DEVELOP EXTREMELY HIGH PRESSURES. FUEL
UNDER THIS AMOUNT OF PRESSURE CAN PENE-
TRATE SKIN AND CAUSE PERSONAL INJURY.
WEAR SAFETY GOGGLES AND ADEQUATE PRO-TECTIVE CLOTHING. AVOID CONTACT WITH FUEL
SPRAY WHEN OPERATING INJECTOR TESTOR.
(4) After injector has been removed, obtain bench-
mount fuel injector tester OTCt(SPXt) part number
4210 (Fig. 16) (or equivalent). Install Special Tool
number 8301 (Fuel Injector Adapter) to 4210 tester.
Install fuel injector into 8301 adapter. Be sure tip of
adapter tool 8301 is aligned to inlet hole at side of
injector (Fig. 17) before tightening tool. Tighten tool
8301 to injector. Position container below injector
before testing.
(5) Refer to operating instructions supplied with
pressure tester for procedures.
(a) Check opening pressure or ªpopº pressure.
Pressure should be approximately 31,026 kPa (310
bars) or (4500 psi6250 psi). If fuel injector needle
valve is opening (popping) too early or too late,
replace injector.
(b) Perform a leak-down test on injector. Apply
pressure with injector tester. The injector should
not leak (drip) fuel with pressure at approximately
20 bars (291 psi) lower than pop pressure.
(c) Operate tester lever quickly several times to
check injector spray pattern. Verify fuel is spraying
from each injector nozzle hole. Injector should also
spray evenly from each nozzle hole.
(d) Pay attention to size and shape of spray
plumes. They should all be equal. If possible, com-
pare spray pattern to that of a new fuel injector
with same part number. Checking each plume for
consistency is an excellent indicator of injector per-
formance. Even if only one nozzle hole is plugged,
significant performance problems could result.
(e) Look for burrs on injector inlet.
(f) Check nozzle holes for hole erosion or plug-
ging.
(g) Inspect end of nozzle for burrs or rough
machine marks.
(h) Look for cracks at nozzle end.
(i) Check nozzle color for signs of overheating.
Overheating will cause nozzle to turn a dark yel-
low/tan or blue (depending on overheating temper-
ature).
(j) Look at end of injector tube where it meets
injector. A small, shiny band should be seen at this
point. The band should have a consistent thick-
ness. If not, injector could be leaking into fuel
return.
(k) If any of these conditions occur, replace injec-
tor.
REMOVAL
The fuel injectors are located in the top of the cyl-
inder head between the intake/exhaust valves (Fig.
18).
Fig. 16 Fuel
1 - FUEL INJECTOR
2 - ADAPTOR TOOL 8301
3 - POP PRESSURE TESTER
Fig. 17 Installing Injector to Adaptor Tool 8301
1 - ADAPTOR TOOL 8301
2 - TIP
3 - FUEL INJECTOR
4 - INLET AT SIDE OF INJECTOR
14 - 96 FUEL INJECTION - DIESELBR/BE
FUEL INJECTOR (Continued)