heating MERCEDES-BENZ SPRINTER 2006 Owners Manual

8W-97 POWER DISTRIBUTION
TABLE OF CONTENTS
page page
POWER DISTRIBUTION
DESCRIPTION..........................1
OPERATION............................1
CIGAR LIGHTER OUTLET
DESCRIPTION..........................1
OPERATION............................2
DIAGNOSIS AND TESTING - CIGAR LIGHTER
OUTLET.............................2
REMOVAL.............................2
CIRCUIT BREAKER
DESCRIPTION..........................2
OPERATION............................2
DIAGNOSIS AND TESTING - CIRCUIT
BREAKER............................2
FUSE BLOCK #1
DESCRIPTION..........................2
OPERATION............................3
REMOVAL.............................3
INSTALLATION..........................3FUSE BLOCK #2
DESCRIPTION..........................3
OPERATION............................3
POWER DISTRIBUTION CENTER
DESCRIPTION..........................3
OPERATION............................3
POWER OUTLET
DESCRIPTION..........................3
OPERATION............................4
DIAGNOSIS AND TESTING - POWER OUTLET . 4
REMOVAL.............................4
INSTALLATION..........................4
RELAY
DESCRIPTION..........................4
OPERATION............................5
DIAGNOSIS AND TESTING - RELAY.........5
REMOVAL.............................5
INSTALLATION..........................5
POWER DISTRIBUTION
DESCRIPTION
This section describes the power distribution com-
ponents used on this model as well as the methods in
which battery voltage and charging system voltage is
distributed throughout the vehicle. The power distri-
bution system for this vehicle consists of the follow-
ing major components which are covered in further
detail later in this section:
²Fuseblock #1
²Fuseblock #2
²Power Distribution Center (PDC)
The power distribution system also incorporates
various types of circuit control and protection fea-
tures, including:
²Automatic resetting circuit breakers
²Blade-type fuses
²Cartridge fuses
²Relays
Following are general descriptions and theory of
operation for the major components in the power dis-
tribution system. Refer to Wiring for the location of
complete circuit diagrams for the various power dis-
tribution system components.
OPERATION
The power distribution system for this vehicle is
designed to provide safe, reliable, and centralized dis-
tribution points for the electrical current required to
operate all of the standard and optional factory-in-
stalled electrical and powertrain, chassis, safety,
security and convenience systems. At the same time,
the power distribution system was designed to pro-
vide easy access to these electrical distribution points
for the vehicle technician to use when conducting
diagnosis and repair of faulty circuits. The power dis-
tribution system can also prove useful for the addi-
tion of electrical circuits that may be required to
operate accessories that the vehicle owner may
choose to have installed in the aftermarket.
CIGAR LIGHTER OUTLET
DESCRIPTION
The cigar lighter outlet is installed in the instru-
ment panel, near the center of the instrument panel.
The cigar lighter outlet is secured by a snap fit
within the instrument panel.
The cigar lighter knob/heating element, and the
cigar lighter outlet are available for service. These
components cannot be repaired and, if faulty or dam-
aged, they must be replaced.
VA8W-97 POWER DISTRIBUTION 8W - 97 - 1

OPERATION
The cigar lighter consists of two major components:
a knob and heating element unit, and the cigar
lighter base or receptacle shell. The receptacle shell
is connected to ground, and an insulated contact in
the bottom of the shell is connected to battery cur-
rent. The cigar lighter receives battery voltage from a
fuse in the fuseblock only when the ignition switch is
in the Accessory or On positions.
The knob and heating element are encased within
a spring-loaded housing, which also features a sliding
protective heat shield. When the heating element is
inserted in the receptacle shell, the heating element
resistor coil is grounded through its housing to the
receptacle shell. If the cigar lighter knob is pushed
inward, the heat shield slides up toward the knob
exposing the heating element.
Two small spring-clip retainers are located on
either side of the insulated contact inside the bottom
of the receptacle shell. These clips engage and hold
the heating element against the insulated contact
long enough for the resistor coil to heat up and glow.
When the resistor coil becomes sufficiently heated,
excess heat radiates from the heating element caus-
ing the spring-clips to expand. Once the spring-clips
expand far enough to release the heating element,
the spring-loaded housing forces the knob and heat-
ing element to pop back outward to their relaxed
position. When the cigar lighter knob and element
are pulled out of the receptacle shell, the protective
heat shield slides downward on the housing so that
the heating element is recessed and shielded around
its circumference for safety.
DIAGNOSIS AND TESTING - CIGAR LIGHTER
OUTLET
For cigar lighter outlet diagnosis and testing pro-
cedures (Refer to 8 - ELECTRICAL/POWER DISTRI-
BUTION/POWER OUTLET - DIAGNOSIS AND
TESTING)
REMOVAL
For cigar lighter outlet removal procedure (Refer to
8 - ELECTRICAL/POWER DISTRIBUTION/POWER
OUTLET - REMOVAL).
CIRCUIT BREAKER
DESCRIPTION
Automatic resetting circuit breakers are used to
protect the power window voltage supply circuits.
These circuit breakers can protect the systems from a
short circuit, or from an overload condition caused byan obstructed or stuck power window regulator or
switch.
The circuit breaker cannot be repaired and, if
faulty or damaged, it must be replaced.
OPERATION
The circuit breaker contains a bi-metal strip sand-
wiched between two contacts forming the connection
in the circuit. An overload condition causes the
bi-metal strip to heat and bend to the open position,
disconnecting current flow to the circuit. Then as the
system overload or short circuit is removed, the
bi-metal strip cools, re-establishing contact to allow
current flow to the circuit.
DIAGNOSIS AND TESTING - CIRCUIT BREAKER
For complete circuit descriptions and diagrams,
refer toWiring.
(1) Locate the correct circuit breaker in the fuse-
block. Pull out the circuit breaker slightly, but be cer-
tain that the circuit breaker terminals still contact
the terminals in the fuseblock cavities.
(2) Connect the negative lead of a 12-volt DC volt-
meter to a good ground.
(3) With the voltmeter positive lead, check both
terminals of the circuit breaker for battery voltage.
If only one terminal has battery voltage, the circuit
breaker is faulty and must be replaced. If neither ter-
minal has battery voltage, repair the open circuit
from the Power Distribution Center as required.
FUSE BLOCK #1
DESCRIPTION
An electrical fuse block is concealed under the
driver side steering column. The fuse block serves to
distribute electrical current to many of the electrical
systems in the vehicle. The fuse block contains blade-
type mini fuses, relays and micro processors that
enable automatic control of some of the power distri-
bution circuits throughout the vehicle.
The molded plastic fuse block housing has an inte-
gral mounting bracket that is secured with screws to
the steering column. A finger recess is molded into
the cover for easy removal. A fuse layout map is
molded onto the back side of the cover to ensure
proper fuse identification.
The fuse block cannot be repaired, if the fuse block
is faulty or damaged or if any internal circuit is
faulty or damaged, the entire fuse block must be
replaced.
8W - 97 - 2 8W-97 POWER DISTRIBUTIONVA

OPERATION
All of the circuits entering and leaving the fuse
block do so through the instrument panel wire har-
ness. Internal connection of all of the fuse block cir-
cuits is accomplished by an intricate combination of
hard wiring and bus bars. Internal relays and micro
processors allow the vehicle electronics to control
some of the power distribution circuits throughout
the vehicle. Refer to the Wiring section for complete
circuit diagrams.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove fuse block cover by rotating locking
screw 90É.
(3) Remove the steering column cover. Refer to the
Body section for the procedure.
(4) Unscrew fuse block connections and disconnect
all electrical connectors from the fuse block.
(5) Remove the fuse block from the steering col-
umn.
INSTALLATION
(1) Position the fuse block in the steering column.
(2) Install fuse block connections and connect all
electrical connectors on the fuse block.
(3) Install the steering column cover. Refer to the
Body section for the procedure.
(4) Install fuse block cover by rotating locking
screw 90É.
(5) Connect the negative battery cable.
(6) Set time and radio stations.
FUSE BLOCK #2
DESCRIPTION
An electrical fuse block is concealed under the
driver side front seat. The fuse block serves to dis-
tribute electrical current to many of the electrical
systems in the vehicle. The fuse block houses blade-
type mini fuses, blade-type automatic resetting cir-
cuit breakers and International Standards
Organization relays. Additional provisions are avail-
able in the fuse block for additional fuses and ISO
relays.
The molded plastic fuse block housing has an inte-
gral mounting bracket that is secured with screws to
the seat base. The driver side seat base also has a
snap-fit fuse access panel that can be removed for
service of the fuses and the relays. A finger recess is
molded into one end for easy removal. A fuse layout
map is molded onto the back side of the panel to
ensure proper fuse identification.
The fuse block is integral to the body wire harness.
If any internal circuit or the fuse block housing isfaulty or damaged, the entire fuse block and body
wire harness unit must be replaced.
OPERATION
All of the circuits entering and leaving the fuse
block do so through the body wire harness. Internal
connection of all of the fuse block circuits is accom-
plished by an intricate combination of hard wiring
and bus bars.
POWER DISTRIBUTION CEN-
TER
DESCRIPTION
All of the electrical current distributed throughout
this vehicle is directed through the Power Distribu-
tion Center (PDC). The molded plastic PDC housing
is located in the left front corner of the engine com-
partment, on the battery positive cable. The PDC
housing has a molded plastic cover that slides over
the PDC housing. The PDC cover is easily opened or
removed for service access.
The PDC unit cannot be repaired and is only ser-
viced as a unit with the headlamp and dash wire
harness. If the internal circuits or the PDC housing
are faulty or damaged, the headlamp and dash wire
harness unit must be replaced.
OPERATION
All of the current from the battery and the gener-
ator output enters the PDC through the positive bat-
tery cable. The PDC cover is removed to access the
battery and generator output connection B(+) termi-
nal studs. Internal connection of all of the PDC cir-
cuits is accomplished by an intricate combination of
hard wiring and bus bars. Refer to Wiring Diagrams
for the location of complete PDC circuit diagrams.
POWER OUTLET
DESCRIPTION
The power outlet is installed in the instrument
panel accessory switch plate, which is located near
the center of the instrument panel. The power outlet
base is secured by a snap fit within the instrument
panel. A plastic protective cap snaps over the power
outlet base when the power outlet is not being used.
While the power outlet is very similar to a cigar
lighter base unit, it does not include the two small
spring-clip retainers inside the bottom of the recepta-
cle shell that are used to secure the cigar lighter
heating element to the insulated contact.
The power outlet receptacle unit are available for
service. The power outlet receptacle cannot be
VA8W-97 POWER DISTRIBUTION 8W - 97 - 3

REMOVAL
WARNING: NO SPARKS, OPEN FLAMES OR SMOK-
ING. RISK OF POISONING FROM INHALING AND
SWALLOWING FUEL. RISK OF INJURY TO EYES
AND SKIN FROM CONTACT WITH FUEL. POUR
FUELS ONLY INTO SUITABLE AND APPROPRI-
ATELY MARKED CONTAINERS. WEAR PROTECTIVE
CLOTHING.
WARNING: RISK OF INJURY TO SKIN AND EYES
FROM SCALDING WITH HOT COOLANT. RISK OF
POISONING FROM SWALLOWING COOLANT. DO
NOT OPEN COOLING SYSTEM UNLESS COOLANT
TEMPERATURE IS BELOW 90ÉC (194ÉF). OPEN CAP
SLOWLY TO RELEASE PRESSURE. STORE COOL-
ANT IN SUITABLE AND APPROPRIATELY MARKED
CONTAINER. WEAR PROTECTIVE GLOVES,
CLOTHES, AND EYE WEAR.
(1) Disconnect the negative battery cable.
NOTE: REPLACE THE AIR CONDITIONING DRIER
WHEN EVER THE AIR CONDITIONING SYSTEM IS
OPENED.
(2) Drain cooling system (Refer to 7 - COOLING/
ENGINE/COOLANT - STANDARD PROCEDURE).
(3) Evacuate and recover air conditioning system
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - STANDARD PROCEDURE).
(4) Remove the front grille and fascia assembly.(5) Disconnect the engine wiring harness at the
cabin side and carefully guide though the cowl into
the engine area.
Fig. 2 ENGINE COVER
1 - ENGINE COVER
2 - FASTENERS
VAENGINE 9 - 5

(6) Remove the turbocharger heat shield (Fig. 3).
(7) Remove the engine cover (Fig. 3).
(8) Remove the air cleaner and hose at the turbo-
charger and air cleaner assembly.
(9) Disconnect the transmission lines at the radia-
tor.
(10) Disconnect the upper and lower radiator
hoses.
(11) Disconnect the A/C lines at the condenser.
(12) Disconnect the condenser fan harness connec-
tor.
(13) Disconnect the power steering cooler lines at
the cooler.
(14) Disconnect the charge air cooler hose at the
intake manifold (Fig. 3).
(15) Remove charge air hose fasteners at the radi-
ator closure panel.
(16) Remove the fasteners retaining the radiator to
the front crossmember.(17) Remove the change air cooler, A/C conderser
and fan as an assembly.
(18) Disconnect the charge air hose at the intake
manifold (Fig. 3).
(19) Remove the radiator assembly.
(20) Disconnect the high pressure and return
hoses at the power steering pump.
(21) Disconnect the fuel lines at the fuel filter.
(22) Disconnect the refrigerant line at the A/C
compressor.
(23) Disconnect the vacuum line for the brake
booster at the vacuum pump (Fig. 3).
(24) Disconnect the coolant hose of heating return
flow at the water pump.
(25) Disconnect the coolant hose of the heater sup-
ply at the coolant pipe at the side of the cylinder
head.
Fig. 3 ENGINE COVER
1 - ENGINE COVER 6 - HIGH PRESSURE FUEL PUMP
2 - FUEL RAIL 7 - VACUUM PUMP
3 - INTAKE MANIFOLD 8 - OIL LEVEL INDICATOR
4 - EGR VALVE 9 - HEAT SHIELD
5 - AIR INLET TUBE 10 - TRANSMISSION OIL LEVEL INDICATOR
9 - 6 ENGINEVA

(11) Install the torque converter access plate. Refer
to (Refer to 21 - TRANSMISSION/TRANSAXLE/AU-
TOMATIC - NAG1 - INSTALLATION) for correct
sequence and torque specification.
(12) Install the transmission cooler lines to trans-
mission. (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - NAG1 - INSTALLATION) for
correct sequence and torque specification.
(13) Connect the engine valley drain hose to the
transmission (Fig. 5).
(14) Install transmission electrical connector and
shifter hardware. Refer to (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - NAG1 - INSTAL-
LATION) for correct sequence and torque
specification.
(15) Install the steering gear and tighten in two
stages. 25 N´m (18.5 lbs. ft.), then 45 N´m (33 lbs. ft.)
plus 90É.
(16) Install the starter.
(17) Connect the ground strap (left side).
(18) Align and install the exhaust and bracket
(Refer to 11 - EXHAUST SYSTEM/EXHAUST PIPE -
INSTALLATION).
(19) Lower the vehicle.
(20) Install the lower heater housing and filter.
(21) Install the air inlet hose, CCV breather and
CCV heater at the turbocharger (Fig. 4).
(22) Connect the coolant supply and return hoses.
(23) Connect the brake booster vacuum hose at the
vacuum pump.(24) Connect the fuel lines at the filter assembly
(Fig. 9).
(25) Connect the power steering hoses.
(26) Install the radiator/charge air cooler and
hose(s) assemblies (Refer to 7 - COOLING/ENGINE/
RADIATOR - INSTALLATION).
(27) Install A/C condenser and fan assemblies Con-
nect the fan harness connector.
(28) Connect the refrigerant lines.
(29) Install a air conditioning receiver/drier (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMB-
ING/RECEIVER / DRIER - INSTALLATION).
(30) Connect the upper and lower radiator hoses.
(31) Connect the transmission lines at the radia-
tor.
(32) Install air cleaner housing and connect the air
inlet duct and air flow sensor.
(33) Connect the charge air cooler hose at intake
manifold. (Refer to 9 - ENGINE/AIR INTAKE SYS-
TEM/AIR CLEANER HOUSING - INSTALLATION).
(34) Route the engine wiring harness inside the
vehicle and connect.
(35) Install the turbocharger heat shield.
(36) Install the front grille and fascia assembly.
(37) Connect the negative battery cable.
(38) Check and fill engine oil (Refer to LUBRICA-
TION & MAINTENANCE/FLUID TYPES - SPECIFI-
CATIONS).
Fig. 8 CRANKSHAFT POSITION SENSOR
1 - ENGINE BLOCK
2 - WIRING HARNESS CONNECTOR
3 - CRANKSHAFT POSITION SENSOR
4 - STARTER SOLENOID
Fig. 9 FUEL FILTER
1 - FUEL SUPPLY FROM TANK
2 - FUEL SUPPLY TO HIGH PRESSURE PUMP
3 - POWER STEERING RESERVOIR
4 - FUEL FILTER
5 - OIL FILTER
6 - WATER IN FUEL SENSOR
9 - 10 ENGINEVA

(4) Use the measurment and table below to group
cylinder bores:
Standard size 88.0 mm
Group code letter A 88.000-88.006 mm
Group code letter X 88.006-88.012 mm
Group code letter B 88.012-88.018 mm
Wear limit in longitudinal
in transverse direction0.020 mm
Permissible variation of
cylinder shape (when
new)0.000-0.014 mm
CRANKSHAFT
DESCRIPTION
The engine features a forged crankshaft supported
by six bearings. The bearing caps are machined
together with the crankshaft and must not be inter-
changed. The bearing surfaces are induction hard-
ened. The connecting rods and main bearing journals
are filleted. An optional vibration damper with a sec-ond pulley is used to drive an additional A/C com-
pressor.
STANDARD PROCEDURE - MEASURE CRANK-
SHAFT AND BLOCK JOURNALS
NOTE: After any bearing damage occurred, remove
all debris which is present in the main oil gallery,
connecting rod bores, and in the crankshaft and oil
galleries. Include removal of the inserting steel ball
of the main oil gallery before cleaning.
(1) Remove crankshaft (Refer to 9 - ENGINE/EN-
GINE BLOCK/CRANKSHAFT - REMOVAL).
(2) Clean all engine parts thoroughly.
CAUTION: After bearing has damage has occurred,
replace connecting rods which have suffered over-
heating because of bearing damage. The connect-
ing rod must not have any cross scores and
notches.
(3) Inspect connecting rod. If damage is present,
inspect crankshaft, replace as necessary.
(4) Inspect crankcase.
Fig. 31 MEASURING CYLINDER BORES
1 - MEASURING POINT OF CYLINDER BORE
2 - MEASURING POINT OF CYLINDER BORE
3 - MEASURING POINT OF CYLINDER BORE
1a - UPPER REVERSAL POINT OF #1 PISTON RING
1b - BOTTOM DEAD CENTER OF PISTON
1c - BOTTOM REVERSAL POINT OF OIL SCRAPER RING
1A - LONGITUDINAL DIRECTION
1B - TRANSVERSE PDIRECTION
VAENGINE 9 - 39

Switching Off Main Injection
Main injection is switched off when:
²Engine speed is too high >4700 - 4800 rpm
²Main injection quantity too low
²Low fuel pressure in fuel rail
²Engine off
²External quantity control
²Deceleration mode
Calculating Main Injection
The quantity of main injection is calculated by:
²Engine speed
²Atmospheric pressure
²Coolant temperature
²Boost air temperature
²Fuel rail pressure
²Boost pressure
Period of Actuation
For calculating the period of actuation of the main
injection it is necessary to know whether a pre-injec-
tion has occurred or not.
The coolant temperature, charge air temperature
and the atmospheric pressure are used for correcting
the main injection quantity. If main injection quan-
tity is less than a minimum quantity which is depen-
dent on fuel rail pressure, no preinjection takes
place. In this case, only main injection is performed.
If the quantity is then still below the minimum
quantity, neither main injection or pre-injection takes
place (deceleration mode).
Deceleration Mode
The purpose of the deceleration mode is to inter-
rupt the operation of the injectors. The ECM deter-
mines the accelerator pedal position from a supplied
signal and it determines the engine speed by the
crank sensor. In the overrun and with the engine
speed above 1600, with the accelerator pedal no
pressed, the injectors are no longer actuated and the
fuel rail pressure is lowered by the pressure regula-
tor valve.
Full Load Injected Quantity
The purpose of the full load injected quantity is to
minimize the formation of smoke. The ECM limits
the fuel rail pressure when the engine is operating at
full load by way of the quantity control valve, and
quantity of fuel injected by the injectors. this mini-
mizes the formation of smoke when accelerating and
driving at constant speeds. If a fault occurs at the
boost pressure control, full load injected quantity is
reduced.
Limiting Maximum Engine Speed
The ECM determines the engine speed based on
the signal supplied by the crankshaft sensor and lim-its this by interrupting the operation of the fuel
injectors.
Fuel Quantity Control
The fuel quantity is controlled separately for each
cylinder by the ECM inline with the firing order.The
ECM detects the operating state which exists at the
engine by means of the sensors. In order adapt the
quantity injected, either the fuel rail pressure can be
adjusted by the fuel solenoid and quantity control
valve or the actuation time of the solenoid valves in
the injectors
Boiling Protection
In order to protect against thermal overload and
along with criteria programmed in the ECM, the
injection quantity is reduced as a function of the cool-
ant temperature and vehicle speed. If the coolant
temperature sensor fails the oil temperature signal
from the oil sensor is used as a suitable value.
Fuel Tank Protection
The fuel rail pressure is lowered in order to protect
the fuel tank from overheating. The fuel temperature
sensor measures the temperature of the fuel being
supplied from the tank, in the high pressure flange.
If the fuel is too warm the fuel rail pressure is fur-
ther reduced by the quantity control valve.
STANDARD PROCEDURE
STANDARD PROCEDURE - DRAINING FUEL
TANK - DIESEL
(1) Position a drain hose into the fuel fill opening.
(2) Drain fuel tank using an approved diesel fuel
draining station.
FUEL CONTAMINATION
If a diesel engine's fuel supply has been contami-
nated with gasoline, the following procedure must be
followed:
(1) Remove all fuel from the fuel tank. (Refer to 14
- FUEL SYSTEM/FUEL DELIVERY - STANDARD
PROCEDURE-DRAINING FUEL TANK) Use an
appropriate fuel container. Dispose of the contami-
nated fuel using the proper procedures.
CAUTION: Dispose of petroleum based products in
a manner consistent with all applicable Local, State,
Federal, and Provincial regulations.
(2) Remove and clean fuel tank. (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/FUEL TANK -
REMOVAL)
(3) Install the fuel tank. (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/FUEL TANK - INSTALLA-
TION)
14 - 8 FUEL DELIVERYVA

(5) Tighten fuel rail bolts to 14 N´m (124 in. lbs.)
(Fig. 19)
CAUTION: When tightening fuel injection line union
nuts, counter hold with a wrench at the thread con-
nection. ON NO ACCOUNT exceed the tightening
torque at any time.
(6) Tighten the pressure line to the fuel rail to 20
N´m (177 in. lbs.).
(7) Tighten the high pressure fuel lines at the fuel
rail to 22 N´m (195 in. lbs.).
(8) Reconnect engine harness electrical connectors.
(9) Connect the intake manifold air inlet duct.
(10) Connect negative battery cable.
CAUTION: Care must be taken when installing the
engine cover. Assure the proper routing of the fuel
injector return fuel hose to the banjo bolt fitting in
the left rear corner of the cover. Failure to do so
may pinch or damage the hose causing fuel leakage
or a driveability concern.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH FAN. DO NOT PUT YOUR
HANDS NEAR PULLEYS, BELTS OR FAN. DO NOT
WEAR LOOSE CLOTHING.
(11) Start engine, run for a few minutes, turn the
engine off and inspect for leaks (Refer to 14 - FUEL
SYSTEM - WARNING).
FUEL TANK
DESCRIPTION
The plastic fuel tank (Fig. 20) is mounted to the
frame rails under the left/center side of the vehicle.
The fuel tank contains a serviceable fuel pump mod-
ule with an electric fuel pump, and a fuel level send-
ing unit. The tank is also equipped with 2 fuel lines:
a fuel supply line to the fuel pump, and a separate
fuel return line.
Fuel Temperature Control:A section of the fuel
return line is coiled at the rear section of the tank
(Fig. 21). This coiled section is used to help drop the
temperature of fuel returning to the tank. A thermo-
stat (preheating valve) (3) (Fig. 21) is used to keep
fuel temperature below 167 degrees F. If fuel temper-
ature is above 167 degrees F, fuel passes first
through the coiled cooler lines, and then into the fuel
tank. If fuel temperature is below 150 degrees F, fuel
bypasses the coiled cooler lines, and is returned
directly into the fuel tank.
An electric fuel pump (more commonly referred to
in diesel applications as a fuel transfer pump or fuel
lift pump) is attached to the fuel pump module. Thismodule (Fig. 22) is located in the fuel tank. Refer to
Fuel Pump Module for additional information.
VAFUEL DELIVERY 14 - 23

Fig. 20 FUEL TANK ASSEMBLY
1 - Strap Bolts (2)
2 - Hose (not with all engines)
3 - Fuel Outlet Line
4 - Fuel Return Line
5 - Plug
6 - Fuel Tank
7 - Tank Straps (2)8 - Nuts (2)
9 - Filler Tube
10 - Vent Hose
11 - Hose
12 - Clamps
13 - Cushioning Material
14 - Two-Way Valve
Fig. 21 FUEL COOLER LINES
1 - Expansion Tank
2-TopofTank
3 - Thermostat (Preheating Valve)
4 - Cooler Lines
5 - Connecting Hoses/Clamps
14 - 24 FUEL DELIVERYVA