service DODGE RAM 2002 Service Service Manual

CLUTCH PEDAL
REMOVAL
(1) Remove knee bolster for access to pedal pivot
shaft.
(2) Remove brake lamp switch.
(3) Remove retaining clips that secure the brake
and clutch pedals to the push rods (Fig. 23).
(4) Remove the brake and clutch master cylinder
pushrods from the pedals.
(5) Remove retainer from passenger side of pedal
pivot shaft (Fig. 24).
(6) Push pedal pivot shaft toward driver side of
support only enough to remove clutch pedal. It is not
necessary to remove shaft from pedal support
entirely.
(7) Remove clutch pedal.
INSTALLATION
Inspect bushings in clutch and brake pedals (Fig.
24). Replace bushings if worn, cracked, or distorted.
(1) Lubricate pedal shaft, pedal shaft bore (Fig. 24)
and all bushings with Mopar Multi Mileage or high
temperature bearing grease.
(2) Position clutch pedal in support. Align pedal
with pivot shaft and slide shaft through pedal bush-
ings. Then repeat process for brake pedal.(3) Slide pedal shaft through support and install
shaft retainer.
(4) Secure push rods to clutch and brake pedals.
(5) Install brake lamp switch in bracket.
(6) Install knee bolster.
LINKAGE
REMOVAL
NOTE: The factory installed hydraulic linkage has a
quick disconnect at the slave cylinder. This fitting
should not be disconnected, the hydraulic linkage
is serviced as an assembly only, but it comes as
two pieces to ease installation. Once the clutch
hydraulic line is connected to the slave cylinder, it
should not be disconnected.
(1) Raise and support vehicle.
(2) Remove nuts attaching slave cylinder to studs
on clutch housing (Fig. 25).
(3) Remove slave cylinder from clutch housing.
(4) Remove the plastic clip securing the hydraulic
line to the dash panel from the lower dash panel
flange.
Fig. 23 Clutch Cylinder And Push Rod
1 - PIN
2 - CLUTCH INTERLOCK WIRE
3 - PUSH ROD
4 - CLIP
Fig. 24 Clutch/Brake Pedal Mounting
1 - PEDAL SUPPORT
2 - SHAFT RETAINER
3 - BRAKE PEDAL
4 - CLUTCH PEDAL
5 - SHAFT RETAINER
6 - PEDAL PIVOT SHAFT
7 - BUSHINGS
BR/BECLUTCH 6 - 15

(5) Remove the plastic clip securing the hydraulic
line to the dash panel from the upper dash panel
stud.
(6) Lower vehicle.
(7) Disconnect clutch pedal interlock switch wires.
(8) Remove retaining clip (Fig. 26).
(9) Slide clutch master cylinder push rod off pedal
pin.
(10) Inspect condition of bushing in the clutch
master cylinder pushrod (Fig. 26). Replace the clutch
hydraulic linkage if bushing is worn or damaged.
(11) Verify that cap on clutch master cylinder res-
ervoir is tight. This will avoid spillage during
removal.
(12) Remove the nuts holding the clutch master
cylinder to the dash panel.
(13) Remove screws that attach clutch fluid reser-
voir to dash panel.
(14) Remove the clutch master cylinder from the
dash panel.
(15) Remove clutch cylinders, reservoir and con-
necting lines from vehicle.
INSTALLATION
NOTE: The factory installed hydraulic linkage has a
quick disconnect at the slave cylinder, this fitting
should not be disconnected. The hydraulic linkage
is serviced as an assembly only, but it comes as
two pieces to ease installation. Once the clutch
hydraulic line is connected to the slave cylinder, it
should not be disconnected.
(1) Tighten cap on clutch fluid reservoir to avoid
spillage during installation.
(2) Position cylinders, connecting lines and reser-
voir in vehicle engine compartment. Locate the clutch
hydraulic line against the dash panel and behind all
engine hoses and wiring.
(3) Insert clutch master cylinder in dash panel.
Install and tighten the nuts to hold the clutch master
cylinder to the dash panel.
(4) Apply a light coating of grease to the inside
and outside diameter of the master cylinder bushing.
(5) Install clutch master cylinder push rod on
clutch pedal pin. Secure rod with retaining clip.
(6) Connect clutch pedal position (interlock) switch
wires.
Fig. 25 Hydraulic Clutch Linkage
1 - DASH PANEL
2 - CYLINDER RESERVOIR
3 - CLUTCH MASTER CYLINDER
4 - SLAVE CYLINDER
5 - CLUTCH HYDRAULIC LINE
Fig. 26 Clutch Cylinder Push Rod Attachment
1 - PIN
2 - CLUTCH INTERLOCK WIRE
3 - PUSH ROD
4 - CLIP
6 - 16 CLUTCHBR/BE
LINKAGE (Continued)

(7) Position clutch fluid reservoir on dash panel
and install reservoir screws. Tighten screws to 5 N´m
(40 in. lbs.).
(8) Install the plastic clip securing the hydraulic
line to the dash panel into the lower dash panel
flange.
(9) Install the plastic clip securing the hydraulic
line to the dash panel onto the upper dash panel
stud.
(10) Raise vehicle.
(11) Install slave cylinder. Be sure cap at end of
cylinder rod is seated in release lever. Check this
before installing cylinder attaching nuts.
NOTE: If new linkage is being installed, do not
remove the plastic shipping strap from slave cylin-
der push rod. The shipping strap will break on its
own upon the first clutch application.
(12) Install and tighten slave cylinder attaching
nuts to 23 N´m (200 in. lbs.).
(13) If a new clutch linkage is being installed, con-
nect the clutch hydraulic line (Fig. 27) to the clutch
slave cylinder.
(14) Lower vehicle.
(15) Operate linkage several times to verify proper
operation.CLUTCH PEDAL POSITION
SWITCH
DESCRIPTION
A clutch pedal position (interlock) switch is in the
starter relay circuit and is mounted on the clutch
master cylinder push rod (Fig. 28). The switch is
actuated by clutch pedal movement.
OPERATION
The switch, which is in circuit with the starter
solenoid, requires that the clutch pedal be fully
depressed in order to start the engine. Switch cir-
cuitry and operation is provided in section 8W of
Group 8.
The position switch is an integral part of the clutch
master cylinder push rod and is not serviced
separately.
Fig. 27 Clutch Slave Cylinder
1 - CLUTCH HYDRAULIC LINE
2 - CLUTCH SLAVE CYLINDER
Fig. 28 Clutch Pedal Position (Interlock) Switch
1 - PIN
2 - CLUTCH INTERLOCK WIRE
3 - PUSH ROD
4 - CLIP
BR/BECLUTCH 6 - 17
LINKAGE (Continued)

DESCRIPTIONÐHOSE CLAMPS
The cooling system utilizes both worm drive and
spring type hose clamps. If a spring type clamp
replacement is necessary, replace with the original
Mopartequipment spring type clamp.
CAUTION: A number or letter is stamped into the
tongue of constant tension clamps. If replacement
is necessary, use only a original equipment clamp
with matching number or letter (Fig. 4).
OPERATION
OPERATIONÐHOSE CLAMPS
The worm type hose clamp uses a specified torque
value to maintain proper tension on a hose connec-
tion.
The spring type hose clamp applies constant ten-
sion on a hose connection. To remove a spring type
hose clamp, only use constant tension clamp pliers
designed to compress the hose clamp.
OPERATIONÐCOOLING SYSTEM
The cooling system regulates engine operating tem-
perature. It allows the engine to reach normal oper-
ating temperature as quickly as possible. It also
maintains normal operating temperature and pre-
vents overheating.
The cooling system also provides a means of heat-
ing the passenger compartment and cooling the auto-
matic transmission fluid (if equipped). The cooling
system is pressurized and uses a centrifugal water
pump to circulate coolant throughout the system.
An optional factory installed maximum duty cool-
ing package is available on most models. This pack-age will provide additional cooling capacity for
vehicles used under extreme conditions such as
trailer towing in high ambient temperatures.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - PRELIMINARY
CHECKS
ENGINE COOLING SYSTEM OVERHEATING
Establish what driving conditions caused the com-
plaint. Abnormal loads on the cooling system such as
the following may be the cause:
²PROLONGED IDLE
²VERY HIGH AMBIENT TEMPERATURE
²SLIGHT TAIL WIND AT IDLE
²SLOW TRAFFIC
²TRAFFIC JAMS
²HIGH SPEED OR STEEP GRADES
Driving techniques that avoid overheating are:
²Idle with A/C off when temperature gauge is at
end of normal range.
²Increasing engine speed for more air flow is rec-
ommended.
TRAILER TOWING:
Consult Trailer Towing section of owners manual.
Do not exceed limits.
AIR CONDITIONING; ADD-ON OR AFTER MARKET:
A maximum cooling package should have been
ordered with vehicle if add-on or after market A/C is
installed. If not, maximum cooling system compo-
nents should be installed for model involved per
manufacturer's specifications.
RECENT SERVICE OR ACCIDENT REPAIR:
Determine if any recent service has been per-
formed on vehicle that may effect cooling system.
This may be:
²Engine adjustments (incorrect timing)
²Slipping engine accessory drive belt(s)
²Brakes (possibly dragging)
²Changed parts. Incorrect water pump or pump
rotating in wrong direction due to belt not correctly
routed
²Reconditioned radiator or cooling system refill-
ing (possibly under filled or air trapped in system).
NOTE: If investigation reveals none of the previous
items as a cause for an engine overheating com-
plaint, (Refer to 7 - COOLING - DIAGNOSIS AND
TESTING)
Fig. 4 Spring Clamp Size Location
1 - SPRING CLAMP SIZE LOCATION
7 - 4 COOLINGBR/BE
COOLING (Continued)

DIAGNOSIS AND TESTINGÐON-BOARD
DIAGNOSTICS (OBD)
COOLING SYSTEM RELATED DIAGNOSTICS
The powertrain control module (PCM) has been
programmed to monitor certain cooling system com-
ponents:
²If the engine has remained cool for too long a
period, such as with a stuck open thermostat, a Diag-
nostic Trouble Code (DTC) can be set.
²If an open or shorted condition has developed in
the relay circuit controlling the electric radiator fan,
a Diagnostic Trouble Code (DTC) can be set.
If the problem is sensed in a monitored circuit
often enough to indicated an actual problem, a DTC
is stored. The DTC will be stored in the PCM mem-
ory for eventual display to the service technician.
(Refer to 25 - EMISSIONS CONTROL - DESCRIP-
TION).
ACCESSING DIAGNOSTIC TROUBLE CODES
To read DTC's and to obtain cooling system data,
(Refer to 25 - EMISSIONS CONTROL - DESCRIP-
TION).
ERASING TROUBLE CODES
After the problem has been repaired, use the DRB
scan tool to erase a DTC. Refer to the appropriate
Powertrain Diagnostic Procedures service informa-
tion for operation of the DRB scan tool.
DIAGNOSIS AND TESTING - COOLING SYSTEM
LEAKS
ULTRAVIOLET LIGHT METHOD
A leak detection additive is available through the
parts department that can be added to cooling sys-
tem. The additive is highly visible under ultraviolet
light (black light). Pour one ounce of additive into
cooling system. Place heater control unit in HEAT
position. Start and operate engine until radiator
upper hose is warm to touch. Aim the commercially
available black light tool at components to be
checked. If leaks are present, black light will cause
additive to glow a bright green color.
The black light can be used in conjunction with a
pressure tester to determine if any external leaks
exist (Fig. 5).
PRESSURE TESTER METHOD
The engine should be at normal operating temper-
ature. Recheck the system cold if cause of coolant
loss is not located during the warm engine examina-
tion.WARNING: HOT, PRESSURIZED COOLANT CAN
CAUSE INJURY BY SCALDING.
Carefully remove radiator pressure cap from filler
neck and check coolant level. Push down on cap to
disengage it from stop tabs. Wipe inside of filler neck
and examine lower inside sealing seat for nicks,
cracks, paint, dirt and solder residue. Inspect radia-
tor-to- reserve/overflow tank hose for internal
obstructions. Insert a wire through the hose to be
sure it is not obstructed.
Inspect cams on outside of filler neck. If cams are
damaged, seating of pressure cap valve and tester
seal will be affected.
Attach pressure tester (7700 or an equivalent) to
radiator filler neck (Fig. 6).
Operate tester pump to apply 103.4 kPa (15 psi)
pressure to system. If hoses enlarge excessively or
bulges while testing, replace as necessary. Observe
gauge pointer and determine condition of cooling sys-
tem according to following criteria:
Holds Steady:If pointer remains steady for two
minutes, serious coolant leaks are not present in sys-
tem. However, there could be an internal leak that
does not appear with normal system test pressure. If
it is certain that coolant is being lost and leaks can-
not be detected, inspect for interior leakage or per-
form Internal Leakage Test.
Drops Slowly:Indicates a small leak or seepage
is occurring. Examine all connections for seepage or
slight leakage with a flashlight. Inspect radiator,
Fig. 5 Leak Detection Using Black LightÐTypical
1 - TYPICAL BLACK LIGHT TOOL
BR/BECOOLING 7 - 5
COOLING (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
COOLANT LOSS TO THE
GROUND WITHOUT PRESSURE
CAP BLOWOFF. GAUGE READING
HIGH OR HOT1. Coolant leaks in radiator, cooling
system hoses, water pump or
engine.1. Pressure test and repair as
necessary. (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING).
DETONATION OR PRE-IGNITION
(NOT CAUSED BY IGNITION
SYSTEM). GAUGE MAY OR MAY
NOT BE READING HIGH1. Engine overheating. 1. Check reason for overheating
and repair as necessary.
2. Freeze point of coolant not
correct. Mixture is too rich or too
lean.2. Check coolant concentration.
(Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION).
HOSE OR HOSES COLLAPSE
WHILE ENGINE IS RUNNING1. Vacuum created in cooling
system on engine cool-down is not
being relieved through coolant
reserve/overflow system.1. (a) Radiator cap relief valve
stuck. (Refer to 7 - COOLING/
ENGINE/RADIATOR PRESSURE
CAP - DIAGNOSIS AND TESTING).
Replace if necessary
(b) Hose between coolant
reserve/overflow tank and radiator is
kinked. Repair as necessary.
(c) Vent at coolant reserve/overflow
tank is plugged. Clean vent and
repair as necessary.
(d) Reserve/overflow tank is
internally blocked or plugged. Check
for blockage and repair as
necessary.
NOISY VISCOUS FAN/DRIVE 1. Fan blades loose. 1. Replace fan blade assembly.
(Refer to 7 - COOLING/ENGINE/
RADIATOR FAN - REMOVAL)
2. Fan blades striking a surrounding
object.2. Locate point of fan blade contact
and repair as necessary.
3. Air obstructions at radiator or air
conditioning condenser.3. Remove obstructions and/or
clean debris or insects from radiator
or A/C condenser.
4. Thermal viscous fan drive has
defective bearing.4. Replace fan drive. Bearing is not
serviceable. (Refer to 7 - COOLING/
ENGINE/FAN DRIVE VISCOUS
CLUTCH - REMOVAL).
5. A certain amount of fan noise
may be evident on models
equipped with a thermal viscous fan
drive. Some of this noise is normal.5. (Refer to 7 - COOLING/ENGINE/
FAN DRIVE VISCOUS CLUTCH -
DESCRIPTION) for an explanation
of normal fan noise.
BR/BECOOLING 7 - 11
COOLING (Continued)

ACCESSORY DRIVE
TABLE OF CONTENTS
page page
BELT TENSIONERS - 5.9L
DESCRIPTION.........................19
OPERATION...........................19
REMOVAL.............................19
INSTALLATION.........................20
BELT TENSIONERS - 8.0L
DESCRIPTION.........................20
OPERATION...........................21
REMOVAL.............................21
INSTALLATION.........................22
BELT TENSIONERS - 5.9L DIESEL
DESCRIPTION.........................23
OPERATION...........................23
REMOVAL.............................23
INSTALLATION.........................23
DRIVE BELTS - 5.9L
DIAGNOSIS AND TESTING - ACCESSORY
DRIVE BELT.........................24
REMOVAL.............................26INSTALLATION.........................26
DRIVE BELTS - 8.0L
DIAGNOSIS AND TESTINGÐACCESSORY
DRIVE BELT.........................27
REMOVAL.............................29
INSTALLATION.........................29
DRIVE BELTS - 5.9L DIESEL
DIAGNOSIS AND TESTINGÐACCESSORY
DRIVE BELT.........................30
REMOVAL.............................32
INSTALLATION.........................32
VACUUM PUMP - 5.9L DIESEL
DESCRIPTION.........................33
OPERATION...........................34
DIAGNOSIS AND TESTINGÐVACUUM PUMP
OUTPUT............................34
REMOVAL.............................34
INSTALLATION.........................36
BELT TENSIONERS - 5.9L
DESCRIPTION
Correct drive belt tension is required to ensure
optimum performance of the belt driven engine acces-
sories. If specified tension is not maintained, belt
slippage may cause; engine overheating, lack of
power steering assist, loss of air conditioning capac-
ity, reduced generator output rate, and greatly
reduced belt life.
It is not necessary to adjust belt tension on the
5.9L engines. These engines are equipped with an
automatic belt tensioner (Fig. 1). The tensioner main-
tains correct belt tension at all times. Due to use of
this belt tensioner, do not attempt to use a belt ten-
sion gauge on 5.9L engines.
OPERATION
The automatic belt tensioner maintains belt ten-
sion by using internal spring pressure, a pivoting
arm and pulley to press against the drive belt.
REMOVAL
WARNING: BECAUSE OF HIGH SPRING PRES-
SURE, DO NOT ATTEMPT TO DISASSEMBLE AUTO-
MATIC TENSIONER. UNIT IS SERVICED AS AN
ASSEMBLY (EXCEPT FOR PULLEY).(1) Remove accessory drive belt. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(2) Disconnect wiring and secondary cable from
ignition coil.
(3) Remove ignition coil from coil mounting
bracket (two bolts). Do not remove coil mounting
bracket from cylinder head.
Fig. 1 Automatic Belt Tensioner - 5.9L Engines
1 - AUTOMATIC TENSIONER
2 - COIL AND BRACKET
3 - SCREW AND WASHER
BR/BEACCESSORY DRIVE 7 - 19

OPERATION
WARNING: THE AUTOMATIC BELT TENSIONER
ASSEMBLY IS SPRING LOADED. DO NOT ATTEMPT
TO DISASSEMBLE THE TENSIONER ASSEMBLY.
The automatic belt tensioner maintains correct belt
tension using a coiled spring within the tensioner
housing. The spring applies pressure to the tensioner
arm pressing the arm into the belt, tensioning the
belt.
If a new belt is being installed, the arrow must be
within approximately 3 mm (1/8 in.) of indexing
mark (point B-) (Fig. 5). Belt is considered new if it
has been used 15 minutes or less. If this specification
cannot be met, check for:
²The wrong belt being installed (incorrect length/
width)
²Worn bearings on an engine accessory (A/C com-
pressor, power steering pump, water pump, idler pul-
ley or generator)
²A pulley on an engine accessory being loose
²Misalignment of an engine accessory²Belt incorrectly routed.
A used belt should be replaced if tensioner index-
ing arrow has moved to point-A (Fig. 5). Tensioner
travel stops at point-A.
REMOVAL
WARNING: BECAUSE OF HIGH SPRING PRES-
SURE, DO NOT ATTEMPT TO DISASSEMBLE AUTO-
MATIC TENSIONER. UNIT IS SERVICED AS AN
ASSEMBLY (EXCEPT FOR PULLEY).
CAUTION: If the pulley is to be removed from the
tensioner, its mounting bolt has left-hand threads.
(1) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(2) Remove tensioner mounting bolt (Fig. 6) and
remove tensioner.
Fig. 4 Indexing MarksÐ8.0L Engines Typical
1 - TENSIONER ASSEMBLY
2 - TENSIONER MOUNTING NUT
3 - INDEXING ARROW
4 - INDEXING MARK
Fig. 5 Indexing MarksÐ8.0L Engines Typical
1 - TENSIONER ASSEMBLY
2 - TENSIONER MOUNTING NUT
3 - INDEXING ARROW
4 - INDEXING MARK
BR/BEACCESSORY DRIVE 7 - 21
BELT TENSIONERS - 8.0L (Continued)

BELT TENSIONERS - 5.9L
DIESEL
DESCRIPTION
Drive belts on all engines are equipped with a
spring loaded automatic belt tensioner (Fig. 9). This
tensioner maintains constant belt tension at all times
and requires no maintenance or adjustment.
CAUTION: Do not attempt to check belt tension with
a belt tension gauge on vehicles equipped with an
automatic belt tensioner.
OPERATION
WARNING: THE AUTOMATIC BELT TENSIONER
ASSEMBLY IS SPRING LOADED. DO NOT ATTEMPT
TO DISASSEMBLE THE TENSIONER ASSEMBLY.
The automatic belt tensioner maintains correct belt
tension using a coiled spring within the tensioner
housing. The spring applies pressure to the tensioner
arm pressing the arm into the belt, tensioning the
belt.
If a new belt is being installed, the arrow must be
within approximately 3 mm (1/8 in.) of indexing
mark. Belt is considered new if it has been used 15
minutes or less. If this specification cannot be met,
check for:
²The wrong belt being installed (incorrect length/
width)²Worn bearings on an engine accessory (A/C com-
pressor, power steering pump, water pump, idler pul-
ley or generator)
²A pulley on an engine accessory being loose
²Misalignment of an engine accessory
²Belt incorrectly routed.
REMOVAL
WARNING: BECAUSE OF HIGH SPRING PRES-
SURE, DO NOT ATTEMPT TO DISASSEMBLE AUTO-
MATIC TENSIONER. UNIT IS SERVICED AS AN
ASSEMBLY.
(1) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(2) Remove tensioner mounting bolt (Fig. 10) and
remove tensioner.
INSTALLATION
(1) Install tensioner assembly to mounting
bracket. A dowel is located on back of tensioner. Align
this dowel to hole in tensioner mounting bracket.
Tighten bolt to 41 N´m (30 ft. lbs.) torque.
(2) Install drive belt (Refer to 7 - COOLING/AC-
CESSORY DRIVE/DRIVE BELTS - INSTALLA-
TION).
Fig. 9 Belt
1 - WATER PUMP
2 - ACCESSORY DRIVE BELT
3 - AUTOMATIC BELT TENSIONER
4 - 3/89SQUARE BOLT
5 - MOUNT. BOLT
Fig. 10 Automatic Belt Tensioner Diesel EngineÐ
Typical
1 - WATER PUMP
2 - ACCESSORY DRIVE BELT
3 - AUTOMATIC BELT TENSIONER
4 - 3/89SQUARE BOLT
5 - MOUNT. BOLT
BR/BEACCESSORY DRIVE 7 - 23

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
7 - 34 ACCESSORY DRIVEBR/BE
VACUUM PUMP - 5.9L DIESEL (Continued)