engine MERCEDES-BENZ SPRINTER 2006 Service Manual
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Page 748 of 2305

(11) Start engine and re-check for vibration. If lit-
tle or no change in vibration is evident, move clamp
to the next positions and repeat vibration test.
NOTE: If there is no difference in vibration at the
other positions, the vibration may not be propeller
shaft.
(12) If vibration decreased, install a second clamp
(Fig. 2) and repeat vibration test.
(13) If additional clamp causes additional vibra-
tion, separate clamps 1/2 inch above and below the
mark. Repeat the vibration test (Fig. 3).(14) Increase distance between clamps and repeat
test until vibration is at the lowest level. Bend the
slack end of the clamps so the screws will not loosen.
(15) If vibration remains unacceptable, preform
the procedure to the front end of the propeller shaft.
(16) Install the wheel and tires. Lower the vehicle.
PROPELLER SHAFT RUNOUT
(1) Clean the propeller shaft surface where the
dial indicator will contact the shaft.
(2) The dial indicator must be installed perpendic-
ular to the shaft surface.
(3) Measure runout at the center and ends of the
shaft away from weld areas, to ensure weld process
will not effect the measurements.
(4) Refer to Runout Specifications chart.
(5) If propeller shaft is out of specification, remove
propeller shaft and index the shaft 180É. Install the
propeller shaft and measure shaft runout again.
(6) If propeller shaft is now within specifications,
mark shaft and yokes for proper orientation.
(7) If propeller shaft runout is not within specifica-
tions, check runout of the transmission and axle.
Correct as necessary and repeat propeller shaft
runout measurement.
(8) Replace propeller shaft if the runout still
exceeds the limits.
Fig. 1 Clamp Screw At Position 1
1 - CLAMP
2 - SCREWDRIVER
Fig. 2 Two Clamp Screws At The Same Position
Fig. 3 Clamp Screws Separated
1-1¤2INCH
VAPROPELLER SHAFT 3 - 3
Page 758 of 2305

LOW SPEED KNOCK
Low speed knock is generally caused by a worn
U-joint or by worn side-gear thrust washers. A worn
pinion shaft bore will also cause low speed knock.
VIBRATION
Vibration at the rear of the vehicle is usually
caused by a:
²Damaged drive shaft.
²Missing drive shaft balance weight(s).
²Worn or out-of-balance wheels.
²Loose wheel lug nuts.
²Worn U-joint(s).
²Loose/broken springs.
²Damaged axle shaft bearing(s).
²Loose pinion gear nut.
²Excessive pinion yoke run out.
²Bent axle shaft(s).
Check for loose or damaged front-end components
or engine/transmission mounts. These components
can contribute to what appears to be a rearend vibra-
tion. Do not overlook engine accessories, brackets
and drive belts.
NOTE: All driveline components should be exam-
ined before starting any repair.
DRIVELINE SNAP
A snap or clunk noise when the vehicle is shifted
into gear (or the clutch engaged), can be caused by:
²High engine idle speed.
²Transmission shift operation.
²Loose engine/transmission/transfer case mounts.
²Worn U-joints.
²Loose spring mounts.
²Loose pinion gear nut and yoke.
²Excessive ring gear backlash.
²Excessive side gear to case clearance.
The source of a snap or a clunk noise can be deter-
mined with the assistance of a helper. Raise the vehi-
cle on a hoist with the wheels free to rotate. Instruct
the helper to shift the transmission into gear. Listen
for the noise, a mechanics stethoscope is helpful in
isolating the source of a noise.
STANDARD PROCEDURE - DRAIN AND FILL
NOTE: Drain oil when warm.
(1) Clean area around oil fill plug and drain plug.
(2) Remove oil drain plug (2) and drain oil (Fig. 1).
(3) Install oil drain plug and tighten to N´m 100
(74 ft. lbs.).
(4) Remove oil fill plug (1) and fill housing up to
bottom edge of oil fill hole (Fig. 1).
(5) Install oil fill plug and tighten to N´m 100 (74
ft. lbs.).
Fig. 1 FILL PLUG
1 - FILL PLUG
2 - DRAIN PLUG
VAREAR AXLE 3 - 13
Page 776 of 2305

DIFFERENTIAL
REMOVAL
(1) Remove differential fill plug.
(2) Remove differential cover and drain fluid.
(3) Remove axle shafts.
(4) Mark bearing caps and housing for installation
reference.
(5) Remove differential bearing cap bolts.
(6) Mount Adapters 9317 (1) (Fig. 30) on differen-
tial housing (2).(7) Position Spreader W-129-B (2) on adapters (1)
(Fig. 31). Mount dial indicator on housing to measure
housing spread.
CAUTION: Never spread over 0.3 mm (0.011 in). If
the housing is over-spread, it could be distorted or
damaged.
(8) Remove differential (2) with bearings, cups (3)
and differential shims (Fig. 32).
(9) Mark bearings and shims for installation refer-
ence.
(10) Clean the housing cavity with flushing oil,
light engine oil or lint free cloth.
NOTE: Do not use water, steam, kerosene or gaso-
line for cleaning.
Fig. 30 SPREADER ADAPTERS
1 - ADAPTERS
2 - DIFFERENTIAL HOUSING
Fig. 31 SPREADER
1 - ADAPTERS
2 - SPREADER
Fig. 32 DIFFERENTIAL REMOVAL
1 - HOUSING
2 - DIFFERENTIAL
3 - DIFFERENTIAL BEARINGS
VAREAR AXLE 3 - 31
Page 791 of 2305

POWER BRAKE BOOSTER
DESCRIPTION.........................19
OPERATION...........................19
REMOVAL.............................20
INSTALLATION.........................20
ROTORS
REMOVAL
REMOVAL - FRONT (SRW)..............20
REMOVAL - REAR (SRW)...............20
REMOVAL - FRONT (DRW)..............21
REMOVAL - REAR (DRW)...............21
INSTALLATION
INSTALLATION - FRONT (SRW)..........22
INSTALLATION - REAR (SRW)...........22
INSTALLATION - FRONT (DRW)..........22
INSTALLATION - REAR (DRW)...........22
SUPPORT PLATE
REMOVAL - REAR......................23
INSTALLATION - REAR...................23
PARKING BRAKE
SPECIFICATIONS
TORQUE CHART......................23
SPECIAL TOOLS
PARK BRAKE........................24
CABLE TENSIONER
REMOVAL.............................24INSTALLATION.........................24
CABLES
REMOVAL
REMOVAL - FRONT....................24
REMOVAL - REAR.....................25
INSTALLATION
INSTALLATION - FRONT................25
INSTALLATION - REAR.................26
ADJUSTMENTS
ADJUSTMENT - PARKING BRAKE CABLES . 26
LEVER
REMOVAL.............................26
INSTALLATION.........................27
SHOES
REMOVAL
REMOVAL - (SRW)....................27
REMOVAL - (DRW)....................27
CLEANING - REAR DRUM IN HAT BRAKE....28
INSTALLATION
INSTALLATION - (SRW).................28
INSTALLATION - (DRW).................28
ADJUSTMENTS
ADJUSTMENT........................28
BRAKES - BASE
DIAGNOSIS AND TESTING - BASE BRAKE SYS-
TEM
Base brake components consist of the brake pads,
calipers, brake drum in hat rotor in the rear, rotors,
brake lines, master cylinder, booster, and parking
brake components.
Brake diagnosis involves determining if the prob-
lem is related to a mechanical, hydraulic, or vacuum
operated component.
The first diagnosis step is the preliminary check.
PRELIMINARY BRAKE CHECK
(1) Check condition of tires and wheels. Damaged
wheels and worn, damaged, or underinflated tires
can cause pull, shudder, vibration, and a condition
similar to grab.
(2) If complaint was based on noise when braking,
check suspension components. Jounce front and rear
of vehicle and listen for noise that might be caused
by loose, worn or damaged suspension or steering
components.
(3) Inspect brake fluid level and condition. Note
that the brake reservoir fluid level will decrease in
proportion to normal lining wear.Also note that
brake fluid tends to darken over time. This is
normal and should not be mistaken for contam-
ination.(a) If fluid level is abnormally low, look for evi-
dence of leaks at calipers, wheel cylinders, brake
lines, and master cylinder.
(b) If fluid appears contaminated, drain out a
sample to examine. System will have to be flushed
if fluid is separated into layers, or contains a sub-
stance other than brake fluid. The system seals
and cups will also have to be replaced after flush-
ing. Use clean brake fluid to flush the system.
(4) Check parking brake operation. Verify free
movement and full release of cables and pedal. Also
note if vehicle was being operated with parking
brake partially applied.
(5) Check brake pedal operation. Verify that pedal
does not bind and has adequate free play. If pedal
lacks free play, check pedal and power booster for
being loose or for bind condition. Do not road test
until condition is corrected.
(6) Check booster vacuum check valve and hose.
(7) If components checked appear OK, road test
the vehicle.
ROAD TESTING
(1) If complaint involved low brake pedal, pump
pedal and note if it comes back up to normal height.
(2) Check brake pedal response with transmission
in Neutral and engine running. Pedal should remain
firm under constant foot pressure.
5 - 2 BRAKES - BASEVA
Page 793 of 2305

As the dragging brake overheats, efficiency is so
reduced that fade occurs. Since the opposite brake
unit is still functioning normally, its braking effect is
magnified. This causes pull to switch direction in
favor of the normally functioning brake unit.
An additional point when diagnosing a change in
pull condition concerns brake cool down. Remember
that pull will return to the original direction, if the
dragging brake unit is allowed to cool down (and is
not seriously damaged).
REAR BRAKE GRAB OR PULL
Rear grab or pull is usually caused by improperly
adjusted or seized parking brake cables, contami-
nated lining, bent or binding shoes and support
plates, or improperly assembled components. This is
particularly true when only one rear wheel is
involved. However, when both rear wheels are
affected, the master cylinder or proportioning valve
could be at fault.
BRAKES DO NOT HOLD AFTER DRIVING THROUGH DEEP
WATER PUDDLES
This condition is generally caused by water soaked
lining. If the lining is only wet, it can be dried by
driving with the brakes very lightly applied for a
mile or two. However, if the lining is both soaked and
dirt contaminated, cleaning and/or replacement will
be necessary.
BRAKE LINING CONTAMINATION
Brake lining contamination is mostly a product of
leaking calipers or worn seals, driving through deep
water puddles, or lining that has become covered
with grease and grit during repair. Contaminated lin-
ing should be replaced to avoid further brake prob-
lems.
WHEEL AND TIRE PROBLEMS
Some conditions attributed to brake components
may actually be caused by a wheel or tire problem.
A damaged wheel can cause shudder, vibration and
pull. A worn or damaged tire can also cause pull.
Severely worn tires with very little tread left can
produce a grab-like condition as the tire loses and
recovers traction. Flat-spotted tires can cause vibra-
tion and generate shudder during brake operation. A
tire with internal damage such as a severe bruise,
cut, or ply separation can cause pull and vibration.
BRAKE NOISES
Some brake noise is common with rear drum
brakes and on some disc brakes during the first few
stops after a vehicle has been parked overnight or
stored. This is primarily due to the formation of trace
corrosion (light rust) on metal surfaces. This light
corrosion is typically cleared from the metal surfacesafter a few brake applications causing the noise to
subside.
BRAKE SQUEAK / SQUEAL
Brake squeak or squeal may be due to linings that
are wet or contaminated with brake fluid, grease, or
oil. Glazed linings and rotors with hard spots can
also contribute to squeak. Dirt and foreign material
embedded in the brake lining will also cause squeak/
squeal.
A very loud squeak or squeal is frequently a sign of
severely worn brake lining. If the lining has worn
through to the brake pads in spots, metal-to-metal
contact occurs. If the condition is allowed to continue,
rotors can become so scored that replacement is nec-
essary.
BRAKE CHATTER
Brake chatter is usually caused by loose or worn
components, or glazed/burnt lining. Rotors with hard
spots can also contribute to chatter. Additional causes
of chatter are out-of-tolerance rotors, brake lining not
securely attached to the shoes, loose wheel bearings
and contaminated brake lining.
THUMP / CLUNK NOISE
Thumping or clunk noises during braking are fre-
quentlynotcaused by brake components. In many
cases, such noises are caused by loose or damaged
steering, suspension, or engine components. However,
calipers that bind on the slide surfaces can generate
a thump or clunk noise.
STANDARD PROCEDURE
STANDARD PROCEDURE - MANUAL BLEEDING
Use approved brake fluid (Refer to LUBRICATION
& MAINTENANCE/FLUID TYPES - DESCRIP-
TION). Use fresh, clean fluid from a sealed container
at all times.
(1) Remove reservoir filler caps and fill reservoir.
(2) If calipers, or wheel cylinders were overhauled,
open all caliper and wheel cylinder bleed screws.
Then close each bleed screw as fluid starts to drip
from it. Top off master cylinder reservoir once more
before proceeding.
(3) Attach one end of bleed hose to bleed screw
and insert opposite end in glass container partially
filled with brake fluid (Fig. 1). Be sure end of bleed
hose is immersed in fluid.
5 - 4 BRAKES - BASEVA
Page 804 of 2305

FLUID
DIAGNOSIS AND TESTING - BRAKE FLUID
CONTAMINATION
Indications of fluid contamination are swollen or
deteriorated rubber parts.
Swollen rubber parts indicate the presence of
petroleum in the brake fluid.
To test for contamination, put a small amount of
drained brake fluid in clear glass jar. If fluid sepa-
rates into layers, there is mineral oil or other fluid
contamination of the brake fluid.
If brake fluid is contaminated, drain and thor-
oughly flush system. Replace master cylinder, ALB
Controller, caliper seals, Antilock Brakes hydraulic
unit and all hydraulic fluid hoses.
STANDARD PROCEDURE - BRAKE FLUID
LEVEL
Always clean the master cylinder reservoir and
caps before checking fluid level. If not cleaned, dirt
could enter the fluid.
The fluid fill level is indicated on the side of the
master cylinder reservoir (Fig. 13).
The correct fluid level is to the MAX indicator on
the side of the reservoir. If necessary, add fluid to the
proper level. (Refer to LUBRICATION & MAINTE-
NANCE/FLUID TYPES - DESCRIPTION).
SPECIFICATIONS
BRAKE FLUID
The brake fluid to be used in this vehicle must be
approved to MB 331.0, such as MOPARtpart num-
ber 0459625AC. If the approved product is not avail-
able, use a DOT 4 brake fluid: minimum dry boiling
point (ERBP) 500ÉF, minimum wet boiling point
(WERBP) 356ÉF, maximum viscosity 1500 mm
2/s,conforming to FMVSS 116 and ISO 4925. No other
type of brake fluid is recommended or approved for
usage in the vehicle brake system. Use only approved
brake fluid or an equivalent from a tightly sealed
container.
Use brake fluid
CAUTION: Never use reclaimed brake fluid or fluid
from an container which has been left open. An
open container of brake fluid will absorb moisture
from the air and contaminate the fluid.
CAUTION: Never use any type of a petroleum-based
fluid in the brake hydraulic system. Use of such
type fluids will result in seal damage of the vehicle
brake hydraulic system causing a failure of the
vehicle brake system. Petroleum based fluids would
be items such as engine oil, transmission fluid,
power steering fluid, etc.
FLUID RESERVOIR
REMOVAL
(1) Using a suction gun remove as much brake
fluid from the reservoir as possible (Fig. 14).
(2) Disconnect the electrical connector for the
brake fluid level indicator (Fig. 14).
(3) Remove the fluid reservoir (Fig. 14).Seal off
the ends and bore holes with plugs.
INSTALLATION
(1) Install the fluid reservoir and fill with fluid
(Fig. 14).
(2) Bleed the brake system.
Fig. 13 FLUID LEVEL TYPICAL
1 - FLUID RESERVOIR
2 - MAX LEVEL MARK
Fig. 14 FLUID RESERVOIR
1 - SUCTION GUN
2 - BRAKE FLUID CAP
3 - BRAKE FLUID LEVEL INDICATOR
4 - MASTER CYLINDER
5 - FLUID RESERVOIR
VABRAKES - BASE 5 - 15
Page 806 of 2305

NOTE: The pressure gauge, connected at the ALB
controller must indicate the outlet pressure which
is assigned on the ALB plate to the rear axle load
determined.
NOTE: If the rear axle load determined is between
two figures indicated on the ALB plate, the outlet
pressure should be determined accordingly.
(8) If the pressure measured differs from the spec-
ification, adjust the ALB controller (Fig. 16).
(9) Loosen the brake pedal winch.
(10) Adjust the outlet pressure by turning the
adjusting nut (Fig. 16)To increase pressure -
tighten the adjusting nut. To reduce pressure -
loosen the adjusting nut.
(11) After adjustment reinstall the brake pedal
winch and recheck the pressures and readjust if
needed.
(12) Tighten the lock adjusting nut.
MASTER CYLINDER
DIAGNOSIS AND TESTING - MASTER CYLIN-
DER / POWER BOOSTER
(1) Start engine and check booster vacuum hose
connections. A hissing noise indicates vacuum leak.
Correct any vacuum leak before proceeding.
(2) Stop engine and shift transmission into Neu-
tral.
(3) Pump brake pedal until all vacuum reserve in
booster is depleted.
(4) Press and hold brake pedal under light foot
pressure. The pedal should hold firm, if the pedal
falls away master cylinder is faulty (internal leak-
age).
(5) Start engine and note pedal action. It should
fall away slightly under light foot pressure then holdfirm. If no pedal action is discernible, power booster,
vacuum supply, or vacuum check valve is faulty. Pro-
ceed to the POWER BOOSTER VACUUM TEST.
(6) If the POWER BOOSTER VACUUM TEST
passes, rebuild booster vacuum reserve as follows:
Release brake pedal. Increase engine speed to 1500
rpm, close the throttle and immediately turn off igni-
tion to stop engine.
(7) Wait a minimum of 90 seconds and try brake
action again. Booster should provide two or more vac-
uum assisted pedal applications. If vacuum assist is
not provided, booster is faulty.
POWER BOOSTER VACUUM TEST
(1) Connect vacuum gauge to booster check valve
with short length of hose and T-fitting (Fig. 17).
(2) Start and run engine at curb idle speed for one
minute.
(3) Observe the vacuum supply. If vacuum supply
is not adequate, repair vacuum supply.
(4) Clamp hose shut between vacuum source and
check valve.
(5) Stop engine and observe vacuum gauge.
(6) If vacuum drops more than one inch HG (33
millibars) within 15 seconds, booster diaphragm or
check valve is faulty.
POWER BOOSTER CHECK VALVE TEST
(1) Disconnect vacuum hose from check valve.
(2) Remove check valve and valve seal from
booster.
Fig. 16 ALB CONTROLLER ADJUSTER NUT
1 - ALB ADJUSTER NUT
2 - SPRING
Fig. 17 Typical Booster Vacuum Test Connections
1 - TEE FITTING
2 - SHORT CONNECTING HOSE
3 - CHECK VALVE
4 - CHECK VALVE HOSE
5 - CLAMP TOOL
6 - INTAKE MANIFOLD
7 - VACUUM GAUGE
VABRAKES - BASE 5 - 17
Page 809 of 2305

edge of the diaphragm is secured to the housing. The
booster push rod, which connects the booster to the
brake pedal and master cylinder, is attached to the
center of the diaphragm. A check valve is used in the
booster outlet connected to the engine intake mani-
fold. Power assist is generated by utilizing a combi-
nation of vacuum and atmospheric pressure to boost
brake assist.
REMOVAL
(1) Using a suction gun remove as much brake
fluid from the reservoir as possible.
(2) Disconnect the brake level switch electrical
connector.
(3) Remove the brake lines from the master cylin-
derSeal off the ends and bore holes with plugs.
(4) Remove the master cylinder from the booster.
(5) Remove the booster vacuum hose and check
valve (Fig. 23).
(6) Remove the pedal push rod clip (Fig. 23).
(7) Remove the booster mounting nuts (Fig. 23).
(8) Remove the booster from the vehicle.
INSTALLATION
(1) Install the brake booster to the vehicle.
(2) Install the booster mounting nuts (Fig. 23).
Tighten to 25 N´m (221 in.lbs.).
(3) Install the push rod pin & clip (Fig. 23).
(4) Install the brake booster vacuum line and
check valve (Fig. 23).
(5) Install the master cylinder to the brake
booster. Tighten to 28 N´m (248 in.lbs.).
(6) Install the brake lines to the master cylinder.
Tighten to 14 N´m (124 in.lbs.).
(7) Install the brake level switch electrical connec-
tor.(8) Bleed the base brake system (Refer to 5 -
BRAKES - STANDARD PROCEDURE).
ROTORS
REMOVAL
REMOVAL - FRONT (SRW)
(1) Raise and support the vehicle.
(2) Remove the front wheels.
(3) Remove the front brake pads (Fig. 24).
(4) Remove the caliper adapter (Fig. 24).
(5) Install two lug studs to secure the disc brake
rotor when the locking bolt is removed.
(6) Remove the locking bolt for the disc brake rotor
(Fig. 24).
(7) Remove the two lug nuts.
(8) Remove the disc brake rotor (Fig. 24).
REMOVAL - REAR (SRW)
(1) Raise and support the vehicle.
(2) Remove the rear wheels.
(3) Remove the rear disc brake pads (Fig. 25).
(4) Remove the disc brake caliper adapter (Fig.
25).
(5) Apply the parking brake.
(6) Install two lug studs to secure the disc brake
rotor when the locking bolt is removed.
(7) Remove the locking bolt for the disc brake rotor
(Fig. 25).
(8) Remove the two lug nuts.
(9) Release the parking brake.
Fig. 23 POWER BRAKE BOOSTER
1 - VACUUM LINE & CHECK VALVE
2 - BRAKE BOOSTER
3 - GASKET
4 - MOUNTING NUTS (4)
5 - PUSH ROD PIN
6 - SECURING CLIP
Fig. 24 FRONT DISC BRAKE ROTOR
1 - CALIPER ADAPTER BOLT
2 - CALIPER ADAPTER
3 - GUIDE BOLT
4 - WEAR INDICATOR
5 - DISC BRAKE CALIPER
6 - DISC BRAKE PADS
7 - LOCKING BOLT
8 - DISC BRAKE ROTOR
5 - 20 BRAKES - BASEVA
Page 828 of 2305

COOLING
TABLE OF CONTENTS
page page
COOLING
OPERATION - COOLING SYSTEM...........1
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - PRELIMINARY
CHECKS.............................1COOLING SYSTEM.....................2
ACCESSORY DRIVE.......................5
ENGINE.................................9
COOLING
OPERATION - COOLING 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.
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)
VACOOLING 7 - 1
Page 829 of 2305

COOLING SYSTEM
COOLING SYSTEM DIAGNOSIS - DIESEL ENGINE
CONDITION POSSIBLE CAUSES CORRECTION
TEMPERATUREGAUGE READS
LOW1. Vehicle is equipped with a
heavy duty cooling system.1. None. System operating norma-
ly.
2. Temperature gauge not connect-
ed2. Connect gauge.
3. Temperature gauge connected
but not operating.3. Check gauge. Refer (Refer to 8
- ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND
TESTING)
4. Coolant level low. 4. Fill cooling system. (Refer to 7 -
COOLING - STANDARD PROCE-
DURE)
TEMPERATURE GAUGE READS
HIGH. COOLANT MAY OR MAY
NOT BE LEAKING FROM SYS-
TEM1. Vehicle overloaded, high ambi-
ent (outside) temperatures with
A/C turned on, stop and go driving
or prolonged operation at idle
speeds.1. Temporary condition, repair not
required. Notify customer of vehicle
operation instructions located in
Owners Manual.
2. Temperature gauge not function-
ing correctly.2. Check gauge. (Refer to 8 -
ELECTRICAL/INSTRUMENT CLUS-
TER - DIAGNOSIS AND TESTING)
3. Air traped in cooling 3. Drain cooling system (Refer to 7
- COOLING - STANDARD PROCE-
DURE) and refill (Refer to 7 -
COOLING - STANDARD PROCE-
DURE)
4. Radiator cap faulty. 4. Replace radiator cap.
5. Plugged A/C or radiator cooling
fins.5. Clean all debre away from A/C
and radiator cooling fins.
6. Coolant mixture incorrect. 6. Drain cooling system (Refer to 7
- COOLING - STANDARD PROCE-
DURE) refill with correct mixture
(Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
7. Thermostat stuck shut. 7. Replace thermostat.
8. Bug screen or winter front being
used.8. Remove bug screen or winter
front.
9. Viscous fan drive not operating
properly.9. Check viscous fan (Refer to 7 -
COOLING/ENGINE/FAN DRIVE
VISCOUS CLUTCH - DIAGNOSIS
AND TESTING)
10. Cylinder head gasket leaking. 10. Check for leaking head gaskets
(Refer to 7 - COOLING - DIAGNO-
SIS AND TESTING).
11. Heater core leaking. 11. Replace heater core.
12. cooling system hoses leaking. 12. Tighten clamps or Replace
hoses.
7 - 2 COOLINGVA