check engine DODGE RAM 2001 Service Manual PDF

The complete assembly must be removed in order
to service either pump. However, the power steering
pump can be removed and serviced separately when
necessary.
The vacuum pump is not a serviceable component.
If diagnosis indicates a pump malfunction, the pump
must be replaced as an assembly. Do not disassemble
or attempt to repair the pump.
The combined vacuum and steering pump assem-
bly must be removed for access to either pump. How-
ever, the vacuum pump can be removed without
having to disassemble the power steering pump.
If the power steering pump requires service, simply
remove the assembly and separate the two pumps.
Refer to the pump removal and installation proce-
dures in this section.
OPERATION
Vacuum pump output is transmitted to the
HEVAC, speed control, systems through a supply
hose. The hose is connected to an outlet port on the
pump housing and uses an in-line check valve to
retain system vacuum when vehicle is not running.
Pump output ranges from a minimum of 8.5 to 25
inches vacuum.
The pump rotor and vanes are rotated by the pump
drive gear. The drive gear is operated by the cam-
shaft gear.
DIAGNOSIS AND TESTINGÐVACUUM PUMP
OUTPUT
The vacuum pump supplies necessary vacuum to
components in the following systems:
²HEVAC system
²Speed Control System
A quick check to determine if the vacuum pump is
the cause of the problem in any of these systems is to
road test the vehicle and verify that all of these sys-
tems are fuctioning properly. If only one of these has
a vacuum related failure, then it is likely the vacuum
pump is not the cause.
A standard vacuum gauge can be used to check
pump output when necessary. Simply disconnect the
pump supply hose and connect a vacuum gauge to
the outlet port for testing purposes. With the engine
running, vacuum output should be a minimum of 25
inches, depending on engine speed.
DIAGNOSING LOW VACUUM OUTPUT CONDITION
If the vacuum pump is suspected of low vacuum
output, check the pump and vacuum harnesses as
follows:
(1) Visually inspect the vacuum harness for obvi-
ous failures (i.e. disconnected, cracks, breaks etc.)
(2) Disconnect the vacuum supply hose at the vac-
uum pump check valve. Connect vacuum gauge to
this valve and run engine at various throttle open-
ings. Output should be a minimum 25 inches of vac-
uum. If vacuum is consistently below 25 inches, the
vacuum pump should be replaced. If output is within
specified limits, the vacuum harness should be sus-
pected as the cause.
(3) Disconnect and isolate the vacuum supply har-
ness. Cap off open ends and apply roughly 15 inches
of vacuum to the harness. If the vacuum gauge does
not hold its reading, then there is an open in the har-
ness and it should be repaired or replaced.
(4) If the vacuum loss is still not detected at this
point, then the pump and harness are not the cause
of the low vacuum condition. Apply vacuum to the
related components of the vacuum supply system (i.e.
valves, servos, solenoids, etc.) to find the source of
the vacuum loss.
REMOVAL
(1) Disconnect battery negative cables.
(2) Position drain pan under power steering pump.
(3) Disconnect vacuum and steering pump hoses.
(4) Disconnect lubricating oil feed line from fitting
at underside of vacuum pump (Fig. 24).
(5) Remove lower bolt that attaches pump assem-
bly to engine block (Fig. 25).
Fig. 23 Diesel Vacuum & Power Steering Pump
Assembly
1 - VACUUM PUMP
2 - POWER STEERING PUMP
3 - PUMP ADAPTER
4 - DRIVE GEAR
BR/BEACCESSORY DRIVE 7 - 35
VACUUM PUMP - 5.9L DIESEL (Continued)

COOLANT RECOVERY
CONTAINER - 3.9L/5.2L/5.9L/
5.9L DIESEL
DESCRIPTION
The coolant reserve/overflow tank is mounted to
the side of the fan shroud (Fig. 1), and is made of
high temperature plastic.
OPERATION
The coolant reserve/overflow system works in con-
junction with the radiator pressure cap. It utilizes
thermal expansion and contraction of coolant to keep
coolant free of trapped air. It provides a volume for
expansion and contraction of coolant. It also provides
a convenient and safe method for checking coolant
level and adjusting level at atmospheric pressure.
This is done without removing the radiator pressurecap. The system also provides some reserve coolant
to the radiator to cover minor leaks and evaporation
or boiling losses.
As the engine cools, a vacuum is formed in the
cooling system of both the radiator and engine. Cool-
ant will then be drawn from the coolant tank and
returned to a proper level in the radiator.
REMOVAL
(1) Remove overflow hose from radiator.
(2) Unsnap the coolant reserve/overflow tank from
fan shroud. Lift straight up. The fan shroud is
equipped with T-shaped slots (Fig. 2) to attach the
tank. An alignment pin is located on the side of tank.
INSTALLATION
(1) Snap the tank into the two T-slots and the
alignment pin on fan shroud (Fig. 3).
(2) Connect overflow hose to radiator.
Fig. 1 Coolant Reserve/Overflow Tank
1 - T-SLOTS
2 - ALIGNMENT PIN
3 - FAN SHROUD
4 - COOLANT RESERVE/OVERFLOW TANK
Fig. 2 COOLANT RESERVE/OVERFLOW TANKÐALL
EXCEPT 8.0L V-10 ENGINE
1 - T-SLOTS
2 - ALIGNMENT PIN
3 - FAN SHROUD
4 - COOLANT RESERVE/OVERFLOW TANK
BR/BEENGINE 7 - 41

COOLANT RECOVERY
CONTAINER - 8.0L
DESCRIPTION
On the 8.0L V-10 engine the tank is mounted to
right inner fender (Fig. 4), and is made of high tem-
perature plastic.
OPERATION
The coolant reserve/overflow system works in con-
junction with the radiator pressure cap. It utilizes
thermal expansion and contraction of coolant to keep
coolant free of trapped air. It provides a volume for
expansion and contraction of coolant. It also provides
a convenient and safe method for checking coolant
level and adjusting level at atmospheric pressure.
This is done without removing the radiator pressure
cap. The system also provides some reserve coolant
to the radiator to cover minor leaks and evaporation
or boiling losses.
As the engine cools, a vacuum is formed in the
cooling system of both the radiator and engine. Cool-
ant will then be drawn from the coolant tank and
returned to a proper level in the radiator.
RADIATOR FAN - 3.9L/5.2L/
5.9L/8.0L
REMOVAL
CAUTION: If the viscous fan drive is replaced
because of mechanical damage, the cooling fan
blades should also be inspected. Inspect for fatigue
cracks, loose blades, or loose rivets that could
have resulted from excessive vibration. Replace fan
blade assembly if any of these conditions are
found. Also inspect water pump bearing and shaft
assembly for any related damage due to a viscous
fan drive malfunction.
(1) Disconnect negative battery cable from battery.
(2) Remove throttle cable at top of fan shroud.
(3) All Except 8.0L V-10 Engine: Unsnap coolant
reserve/overflow tank from fan shroud and lay aside.
The tank is held to shroud with T- shaped slots. Do
not disconnect hose or drain coolant from tank.
(4) The thermal viscous fan drive/fan blade assem-
bly is attached (threaded) to water pump hub shaft
(Fig. 6). Remove fan blade/viscous fan drive assembly
from water pump by turning mounting nut counter-
clockwise as viewed from front. Threads on viscous
fan drive areRIGHT-HAND.A Snap-On 36 MM Fan
Wrench (number SP346 from Snap-On Cummins Die-
sel Tool Set number 2017DSP), Special Tool 6958
Spanner Wrench and Adapter Pins 8346 should be
used to prevent pulley from rotating (Fig. 5).
(5) Do not attempt to remove fan/viscous fan drive
assembly from vehicle at this time.
Fig. 3 COOLANT RESERVE/OVERFLOW TANKÐALL
EXCEPT 8.0L V-10 ENGINE
1 - T-SLOTS
2 - ALIGNMENT PIN
3 - FAN SHROUD
4 - COOLANT RESERVE/OVERFLOW TANK
Fig. 4 Coolant Reserve/Overflow TankÐ8.0L V-10
Engine
1 - COOLANT RESERVE/OVERFLOW TANK
2 - TANK MOUNTING BOLTS (3)
3 - ICM MOUNTING BOLTS (2)
4 - IGNITION CONTROL MODULE (ICM)
7 - 42 ENGINEBR/BE
COOLANT RECOVERY CONTAINER - 3.9L/5.2L/5.9L/5.9L DIESEL (Continued)

(3) Inspect fan assembly for cracks, bends, loose
rivets or broken welds. Replace fan if any damage is
found.
INSTALLATION
(1) Install fan blade assembly to viscous fan drive.
Tighten mounting bolts to 23 N´m (17 ft. lbs.) torque.
(2) Position the fan shroud and fan blade/viscous
fan drive to the vehicle as an assembly.
(3) Install viscous fan drive assembly on fan hub
shaft (Fig. 7). Tighten mounting nut to 57 N´m (42 ft.
lbs.) torque.
(4) Install fan shroud bolts into position and
tighten the mounting bolts to 6 N´m (50 in. lbs.)
torque.
(5) Connect the battery negative cables.
NOTE: Viscous Fan Drive Fluid Pump Out Require-
ment: After installing a new viscous fan drive, bring
the engine speed up to approximately 2000 rpm and
hold for approximately two minutes. This will
ensure proper fluid distribution within the drive.
ENGINE BLOCK HEATER -
3.9L/5.2L/5.9L
DESCRIPTION
WARNING: DO NOT OPERATE ENGINE UNLESS
BLOCK HEATER CORD HAS BEEN DISCONNECTED
FROM POWER SOURCE AND SECURED IN PLACE.
THE POWER CORD MUST BE SECURED IN ITS
RETAINING CLIPS AND ROUTED AWAY FROM
EXHAUST MANIFOLDS AND MOVING PARTS.
An optional engine block heater is available on all
models. The heater is equipped with a power cord.
The heater is mounted in a core hole of the engine
cylinder block (in place of a freeze plug) with the
heating element immersed in engine coolant. The
cord is attached to an engine compartment compo-
nent with tie-straps.
The 3.9L and 5.9L gas powered engine has the
block heater located on the right side of engine next
to the oil filter (Fig. 8).
OPERATION
The heater warms the engine coolant providing
easier engine starting and faster warm-up in low
temperatures. Connecting the power cord to a
grounded 110-120 volt AC electrical outlet with a
grounded three wire extension cord provides the elec-
tricity needed to heat the element..
REMOVAL
(1) Disconnect battery negative cable.
(2) Drain coolant (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
(3) Remove power cord from heater by unplugging
(Fig. 9).
(4) Loosen (but do not completely remove) the
screw at center of block heater (Fig. 9).
(5) Remove block heater by carefully prying from
side-to-side. Note direction of heating element coil
(up or down). Element coil must be installed correctly
to prevent damage.
INSTALLATION
(1) Clean and inspect the block heater hole.
(2) Install new O-ring seal(s) to heater in gasoline
engines.
(3) Insert block heater into cylinder block.
(4) With heater fully seated, tighten center screw
to 2 N´m (17 in. lbs.).
(5) Fill cooling system with recommended coolant.
(Refer to 7 - COOLING - STANDARD PROCE-
DURE).
(6) Start and warm the engine.
(7) Check block heater for leaks.
Fig. 8 Engine Block Heater
1 - FREEZE PLUG HOLE
2 - BLOCK HEATER
3 - SCREW
4 - POWER CORD (120V AC)
5 - HEATING COIL
6 - OIL FILTER
BR/BEENGINE 7 - 45
RADIATOR FAN - 5.9L DIESEL (Continued)

(5) Fill cooling system with recommended coolant
(Refer to 7 - COOLING - STANDARD PROCE-
DURE).
(6) Start and warm the engine.
(7) Check block heater for leaks.
ENGINE BLOCK HEATER - 5.9L
DIESEL
DESCRIPTION
WARNING: DO NOT OPERATE ENGINE UNLESS
BLOCK HEATER CORD HAS BEEN DISCONNECTED
FROM POWER SOURCE AND SECURED IN PLACE.
THE POWER CORD MUST BE SECURED IN ITS
RETAINING CLIPS AND ROUTED AWAY FROM
EXHAUST MANIFOLDS AND MOVING PARTS.
An optional engine block heater is available on all
models. The heater is equipped with a power cord.
The heater is mounted in a core hole of the engine
cylinder block (in place of a freeze plug) with the
heating element immersed in engine coolant. The
cord is attached to an engine compartment compo-
nent with tie-straps.The 5.9L diesel engine has the block heater located
on the right side of the engine below the exhaust
manifold next to the oil cooler (Fig. 12).
OPERATION
The heater warms the engine coolant providing
easier engine starting and faster warm-up in low
temperatures. Connecting the power cord to a
grounded 110-120 volt AC electrical outlet with a
grounded three wire extension cord provides the elec-
tricity needed to heat the element..
REMOVAL
(1) Disconnect the battery negative cables.
(2) Drain coolant from radiator and cylinder block
(Refer to 7 - COOLING - STANDARD PROCE-
DURE).
(3) Unscrew the power cord retaining cap and dis-
connect cord from heater element.
(4) Using a suitable size socket, loosen and remove
the block heater element (Fig. 13).
INSTALLATION
(1) Clean and inspect the threads in the cylinder
block.
(2) Coat heater element threads with Mopart
Thread Sealer with Teflon.
(3) Screw block heater into cylinder block and
tighten to 43 N´m (32 ft. lbs.).
(4) Connect block heater cord and tighten retain-
ing cap.
(5) Fill cooling system with recommended coolant
(Refer to 7 - COOLING - STANDARD PROCE-
DURE).
(6) Start and warm the engine.
(7) Check block heater for leaks.
Fig. 11 Block HeaterÐ8.0L V-10 Engine
1 - FREEZE PLUG HOLE
2 - SCREW
3 - POWER CORD (120V AC)
4 - BLOCK HEATER
5 - HEATING COIL
Fig. 12 Engine Block HeaterÐ5.9L Diesel Engine
1 - BLOCK HEATER
BR/BEENGINE 7 - 47
ENGINE BLOCK HEATER - 8.0L (Continued)

(4) Position thermostat housing to intake manifold.
Note the word FRONT stamped on housing (Fig. 20).
For adequate clearance, thismustbe placed towards
front of vehicle. The housing is slightly angled for-
ward after installation to intake manifold.
(5) Install two housing-to-intake manifold bolts.
Tighten bolts to 23 N´m (200 in. lbs.) torque.
(6) Install radiator upper hose to thermostat hous-
ing.
CAUTION: When installing the serpentine accessory
drive belt, the belt must be routed correctly. If not,
engine may overheat due to water pump rotating in
wrong direction. Refer to (Fig. 21) for correct 3.9L,
5.2L and 5.9L engine belt routing. The correct belt
with correct length must be used.
(7) Air Conditioned vehicles; Install generator.
Tighten bolts to 41 N´m (30 ft. lbs.).
(8) Install support bracket (generator mounting
bracket-to-intake manifold) (Fig. 16). Tighten bolts to
54 N´m (40 ft. lbs.) torque.
(9) Install accessory drive belt (Fig. 17)(Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(10) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(11) Connect battery negative cable.(12) Start and warm the engine. Check for leaks.
Fig. 19 ThermostatÐ3.9L and 5.9L Engines
1 - THERMOSTAT HOUSING
2 - GASKET
3 - INTAKE MANIFOLD
4 - THERMOSTAT
5 - MACHINED GROOVEFig. 20 Thermostat PositionÐ5.2L and 5.9L Engines
Fig. 21 Belt RoutingÐ5.2L and 5.9L Engines
1 - IDLER PULLEY
2 - GENERATOR PULLEY
3 - A/C COMPRESSOR PULLEY
4 - IF W/OUT A/C
5 - POWER STEERING PUMP PULLEY
6 - WATER PUMP PULLEY
7 - CRANKSHAFT PULLEY
8 - AUTOMATIC TENSIONER
BR/BEENGINE 7 - 51
ENGINE COOLANT THERMOSTAT - 3.9L/5.2L/5.9L (Continued)

(3) Remove the two support rod mounting bolts
and remove support rod (intake manifold-to-genera-
tor mount) (Fig. 24).
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER
6094). SNAP-ON CLAMP TOOL (NUMBER HPC-20)
MAY BE USED FOR LARGER CLAMPS. ALWAYS
WEAR SAFETY GLASSES WHEN SERVICING CON-
STANT TENSION CLAMPS.CAUTION: A number or letter is stamped into the
tongue of constant tension clamps . If replacement
is necessary, use only an original equipment clamp
with a matching number or letter.
(4) Remove upper radiator hose clamp. Remove
upper radiator hose at thermostat housing.
(5) Disconnect the wiring connectors at both of the
sensors located on thermostat housing.
(6) Remove six thermostat housing mounting bolts,
thermostat housing and thermostat.
INSTALLATION
(1) Clean mating areas of intake manifold and
thermostat housing.
(2) Check the condition (for tears or cracks) of the
rubber thermostat seal located in the intake manifold
(Fig. 23) (Fig. 25). The thermostat should fit snugly
into the rubber seal.
(3) If seal replacement is necessary, coat the outer
(metal) portion of the seal with MopartGasket
Maker. Install the seal into the manifold using Spe-
Fig. 23 Thermostat SealÐ8.0L V-10 Engine
1 - METAL SEAL SHOULDER
2 - RUBBER LIP SEAL
3 - THERMOSTAT OPENING
Fig. 24 Support RodÐ8.0L V-10 Engine
1 - BOLTS
2 - SUPPORT ROD
Fig. 25 ThermostatÐ8.0L V-10 Engine
1 - COOLANT TEMP. SENSOR (FOR PCM)
2 - HEATER SUPPLY FITTING
3 - BOLTS (6)
4 - HOUSING WITH INTEGRAL SEAL
5 - THERMOSTAT
6 - RUBBER LIP SEAL
7 - TEMP. GAUGE SENDING UNIT
BR/BEENGINE 7 - 53
ENGINE COOLANT THERMOSTAT - 8.0L (Continued)

cial Seal Tool number C-3995-A with handle tool
number C-4171.
(4) Install thermostat into recessed machined
groove on intake manifold (Fig. 25).
(5) Install thermostat housing (Fig. 25).
(6) Install housing-to-intake manifold bolts.
Tighten bolts to 25 N´m (220 in. lbs.) torque.
CAUTION: Housing bolts should be tightened
evenly to prevent damage to housing and to pre-
vent leaks.
(7) Connect the wiring to both sensors.
(8) Install the upper radiator hose and hose clamp
to thermostat housing.
(9) Install support rod.
(10) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(11) Connect negative battery cable to battery.
(12) Start and warm engine. Check for leaks.
ENGINE COOLANT
THERMOSTAT - 5.9L DIESEL
DESCRIPTION
CAUTION: Do not operate an engine without a ther-
mostat, except for servicing or testing. An engine
with the thermostat removed will operate in the
radiator bypass mode, causing an overheat condi-
tion.
The thermostat of the 5.9L diesel engine is located
in the front of the cylinder head, underneath the
water outlet connector (Fig. 26).
The same thermostat is used for winter and sum-
mer seasons. An engine should not be operated with-
out a thermostat, except for servicing or testing.
Operating without a thermostat causes longer engine
warmup time, unreliable warmup performance,
increased exhaust emissions and crankcase condensa-
tion that can result in sludge formation.
OPERATION
The wax pellet is located in a sealed container at
the spring end of the thermostat. When heated, the
pellet expands, overcoming closing spring tension
and water pump pressure to force the valve to open.
DIAGNOSIS AND TESTINGÐTHERMOSTAT
The cooling system used with the diesel engine
provides the extra coolant capacity and extra cooling
protection needed for higher GVWR (Gross Vehicle
Weight Rating) and GCWR (Gross Combined Weight
Rating) vehicles.This system capacity will not effect warm up or
cold weather operating characteristics if the thermo-
stat is operating properly. This is because coolant
will be held in the engine until it reaches the ther-
mostat ªsetº temperature.
Diesel engines, due to their inherent efficiency are
slower to warm up than gasoline powered engines,
and will operate at lower temperatures when the
vehicle is unloaded. Because of this, lower tempera-
ture gauge readings for diesel versus gasoline
engines may, at times be normal.
Typically, complaints of low engine coolant temper-
ature are observed as low heater output when com-
bined with cool or cold outside temperatures.
To help promote faster engine warm-up, the elec-
tric engine block heater must be used with cool or
cold outside temperatures. This will help keep the
engine coolant warm when the vehicle is parked. Use
the block heater if the outside temperature is below
4ÉC (40ÉF).Do not use the block heater if the
outside temperature is above 4ÉC (40ÉF).
A ªCold Weather Coverº is available from the parts
department through the Mopar Accessories product
line. This accessory cover is designed to block airflow
entering the radiator and engine compartment to
promote faster engine warm-up. It attaches to the
front of the vehicle at the grill opening.The cover is
Fig. 26 ThermostatÐ5.9L DieselÐTypical
1 - WATER OUTLET CONNECTOR
2 - THERMOSTAT HOUSING
3 - THERMOSTAT
7 - 54 ENGINEBR/BE
ENGINE COOLANT THERMOSTAT - 8.0L (Continued)

to be used with cool or cold temperatures only.
If used with high outside temperatures, serious
engine damage could result.Refer to the litera-
ture supplied with the cover for additional informa-
tion.
(1) To determine if the thermostat is defective, it
must be removed from the vehicle (Refer to 7 -
COOLING/ENGINE/ENGINE COOLANT THERMO-
STAT - REMOVAL).
(2) After the thermostat has been removed, exam-
ine the thermostat and inside of thermostat housing
for contaminants. If contaminants are found, the
thermostat may already be in a ªstuck openº position.
Flush the cooling system before replacing thermostat
(Refer to 7 - COOLING - STANDARD PROCE-
DURE).
(3) Place the thermostat into a container filled
with water.
(4) Place the container on a hot plate or other suit-
able heating device.
(5) Place a commercially available radiator ther-
mometer into the water.
(6) Apply heat to the water while observing the
thermostat and thermometer.
(7) When the water temperature reaches 83ÉC
(181ÉF) the thermostat should start to open (valve
will start to move). If the valve starts to move before
this temperature is reached, it is opening too early.
Replace thermostat. The thermostat should be fully
open (valve will stop moving) at 95ÉC (203ÉF). If the
valve is still moving when the water temperature
reaches 203É, it is opening too late. Replace thermo-
stat. If the valve refuses to move at any time, replace
thermostat.
REMOVAL
WARNING: DO NOT LOOSEN THE RADIATOR
DRAINCOCK WITH THE SYSTEM HOT AND PRES-
SURIZED. SERIOUS BURNS FROM THE COOLANT
CAN OCCUR.
Do not waste reusable coolant. If the solution is
clean, drain the coolant into a clean container for
reuse.
(1) Disconnect the battery negative cables.
(2) Drain cooling system until coolant level is
below thermostat (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER
6094). SNAP-ON CLAMP TOOL (NUMBER HPC-20)
MAY BE USED FOR LARGER CLAMPS. ALWAYSWEAR SAFETY GLASSES WHEN SERVICING CON-
STANT TENSION CLAMPS.
CAUTION: A number or letter is stamped into the
tongue of constant tension clamps. If replacement
is necessary, use only an original equipment clamp
with a matching number or letter.
(3) Remove radiator hose clamp and hose from
thermostat housing.
(4) Remove the three (3) water outlet-to-cylinder
head bolts and remove the water outlet connector
(Fig. 27).
(5) Clean the mating surfaces of the water outlet
connector and clean the thermostat seat groove at
the top of the thermostat housing (Fig. 27).
INSTALLATION
(1) Install the thermostat into the groove in the
top of the thermostat housing (Fig. 27).
(2) Install the water outlet connector and bolts.
Tighten the bolts to 24 N´m (18 ft. lbs.) torque.
(3) Install the radiator upper hose and clamp.
(4) Fill the cooling system with coolant (Refer to 7
- COOLING - STANDARD PROCEDURE).
(5) Connect the battery negative cables.
(6) Start the engine and check for coolant leaks.
Run engine to check for proper thermostat operation.
Fig. 27 Thermostat Removal/Installation
1 - WATER OUTLET CONNECTOR
2 - THERMOSTAT HOUSING
3 - THERMOSTAT
BR/BEENGINE 7 - 55
ENGINE COOLANT THERMOSTAT - 5.9L DIESEL (Continued)

and compressed air to the back (engine side) of the
radiator to flush the radiator and/or A/C condenser of
debris.
INSPECTION
Inspect the radiator side tanks for cracks, broken
or missing fittings also inspect the joint where the
tanks seam up to the radiator core for signs of leak-
age and/or deteriorating seals.
Inspect radiator core for corroded, bent or missing
cooling fins. Inspect the core for bent or damaged
cooling tubes.
INSTALLATION
(1) Position fan shroud over the fan blades rear-
ward towards engine.
(2) Install rubber insulators to alignment dowels
at lower part of radiator.
(3) Lower the radiator into position while guiding
the two alignment dowels into lower radiator sup-
port. Different alignment holes are provided in the
lower radiator support for each engine application.
(4) Install two upper radiator mounting bolts.
Tighten bolts to 11 N´m (95 in. lbs.) torque.
(5) Position the rubber shields to the sides of radi-
ator. Install the plastic clips retaining the rubber
shields to the sides of radiator.
(6) Connect both radiator hoses and install hose
clamps.
(7) Install windshield washer reservoir tank.
(8) Position fan shroud to flanges on sides of radi-
ator. Install fan shroud mounting bolts (Fig. 34).
Tighten bolts to 6 N´m (50 in. lbs.) torque.
(9) Install coolant reserve/overflow tank hose to
radiator filler neck nipple.
(10) Install coolant reserve/overflow tank to fan
shroud (fits into T-slots on shroud).
(11) Install battery negative cables.
(12) Position heater controls tofull heatposition.
(13) Fill cooling system with coolant (Refer to 7 -
COOLING - STANDARD PROCEDURE).
(14) Operate engine until it reaches normal tem-
perature. Check cooling system fluid levels.
RADIATOR - 8.0L
DESCRIPTION
The radiator is a aluminum cross-flow design with
horizontal tubes through the radiator core and verti-
cal plastic side tanks (Fig. 36).
This radiator contains an internal transmission oil
cooler only on the V-10 gas engine and the 5.9L die-
sel engine combinations.
OPERATION
The radiator supplies sufficient heat transfer using
the cooling fins interlaced between the horizontal
tubes in the radiator core to cool the engine.
DIAGNOSIS AND TESTINGÐRADIATOR
COOLANT FLOW
Use the following procedure to determine if coolant
is flowing through the cooling system.
(1) Idle engine until operating temperature is
reached. If the upper radiator hose is warm to the
touch, the thermostat is opening and coolant is flow-
ing to the radiator.
WARNING: HOT, PRESSURIZED COOLANT CAN
CAUSE INJURY BY SCALDING. USING A RAG TO
COVER THE RADIATOR PRESSURE CAP, OPEN
RADIATOR CAP SLOWLY TO THE FIRST STOP. THIS
WILL ALLOW ANY BUILT-UP PRESSURE TO VENT
TO THE RESERVE/OVERFLOW TANK. AFTER PRES-
SURE BUILD-UP HAS BEEN RELEASED, REMOVE
CAP FROM FILLER NECK.
(2) Drain a small amount of coolant from the radi-
ator until the ends of the radiator tubes are visible
through the filler neck. Idle the engine at normal
operating temperature. If coolant is flowing past the
exposed tubes, the coolant is circulating.
Fig. 36 Cross Flow RadiatorÐTypical
1 - COOLING TUBES
2 - TANKS
BR/BEENGINE 7 - 61
RADIATOR - 3.9L/5.2L/5.9L (Continued)