engine MERCEDES-BENZ ML320 1997 Complete Repair Manual

302 Technical dataFuels, coolants, lubricants etc.Engine oils
Engine oils are specifically tested for their
suitability in our engines. Therefore, use
only engine oils approved by
Mercedes-Benz. Information on approved
engine oils is available in the Factory
Approved Service Products pamphlet, or at
your authorized Mercedes-Benz Light
Truck Center.
Engine oil additives
Do not blend oil additives with engine oil.
They may damage the engine.
Damage or malfunctions resulting from
blending oil additives are not covered by
the Mercedes-Benz Limited Warranty.Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG
lubricating oil is used in the air condition-
ing system.
Never use R-12 (CFC) or mineral-based lu-
bricating oil. Otherwise damage to the
system will occur.
Brake fluid
During vehicle operation, the boiling point
of the brake fluid is continuously reduced
through the absorption of moisture from
the atmosphere. Under extremely strenu-
ous operating conditions, this moisture
content can lead to the formation of bub-
bles in the system, thus reducing the sys-
tem’s efficiency.
Therefore, the brake fluid must be re-
placed every two years, preferably in the
spring.
Only brake fluid approved by
Mercedes-Benz is recommended. Your au-
thorized Mercedes-Benz Light Truck
Center will provide you with additional in-
formation.
!Always check the oil filler cap
(page 221) for important information
pertaining to the engine oil needing to
meet a specific Mercedes-Benz specifi-
cation (e.g. MB 229.5). If such informa-
tion is printed on the oil filler cap, only
use an engine oil from the list of ap-
proved engine oils in the Factory Ap-
proved Service Products pamphlet that
meets the specification indicated on
the oil filler cap.
Using engine oils of other specification
may cause the FSS to incorrectly deter-
mine the next service interval and will
result in engine damage not covered by
the Mercedes-Benz Limited Warranty.

303 Technical data
Fuels, coolants, lubricants etc.
Premium unleaded gasoline
Fuel requirements
Use only premium unleaded meeting
ASTM standard D 439:

The octane number (posted at the
p um p) m us t be 91 mi n. It i s an a vera ge
of both the Research (R) octane num-
ber and the Motor (M) octane number:
(R+M) / 2). This is also known as the
ANTI-KNOCK INDEX.
Unleaded gasoline containing oxygenates
such as ethanol, IPA, IBA and TBA can be
used provided the ratio of any one of these
oxygenates to gasoline does not exceed
10%; MTBE must not exceed 15%.
The ratio of methanol to gasoline must not
exceed 3% plus additional cosolvents.
Using mixtures of ethanol and methanol is
not allowed. Gasohol, which contains 10%
ethanol and 90% unleaded gasoline, can be
used.
These blends must also meet all other fuel
requirements, such as resistance to spark
knock, boiling range, vapor pressure, etc.
Gasoline additives
A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz recommends only the
use of quality gasoline containing additives
that prevent the build-up of carbon depos-
its.
After an extended period of using fuels
without such additives, carbon deposits
can build up especially on the intake valves
and in the combustion area, leading to en-
gine performance problems such as:

Warm-up hesitation


Unstable idle


Knocking / pinging


Misfire


Power loss
Do not blend other specific fuel additives
with fuel. This only results in unnecessary
costs and may be harmful to the engine
operation.
!To maintain the engine’s durability and
performance, premium unleaded gaso-
l i n e m u s t b e u s e d . I f p r e m i u m u n l e a d e d
is not available and low octane fuel is
used, follow these precautions:

Have the fuel tank only partially
filled with unleaded regular and fill
up with premium unleaded as soon
as possible.


Avoid full throttle driving and abrupt
acceleration.


Do not exceed an engine speed of
3000 rpm if the vehicle is loaded
with a light load such as two per-
sons and no luggage.


Do not exceed
2/3 of maximum ac-
celerator pedal position if the vehi-
cle is fully loaded or operating in
mountainous terrain.

304 Technical dataFuels, coolants, lubricants etc.Damage or malfunctions resulting from
poor fuel quality or from blending specific
fuel additives are not covered by the
Mercedes-Benz Limited Warranty.Coolants
The engine coolant is a mixture of water
and anticorrosion / antifreeze, which pro-
vides:

Corrosion protection


Freeze protection


Boiling protection (by increasing the
boiling point)
The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -35°F (-37°C) and corro-
sion protection.
If the antifreeze mixture is effective to
-22°F (-30°C), the boiling point of the cool-
ant in the pressurized cooling system is
reached at approximately 266°F (130°C).The coolant solution must be used year
round to provide the necessary corrosion
protection and increase in boil-over pro-
tection. Refer to Service Booklet for
replacement interval.
To provide important corrosion protection,
the solution must be at least 45%
anticorrosion / antifreeze (equivalent to
freeze protection to approx. - 22°F
[-30°C]). If you use a solution that is more
than 55% anticorrosion / antifreeze (freeze
protection to approx. - 49°F [-45°C]), the
engine temperature will increase due to
the lower heat transfer capability of the so-
lution. Therefore, do not use more than
this amount of anticorrosion / antifreeze.If the coolant level is low, water and MB
anticorrosion / antifreeze should be used
to bring it up to the proper level (have cool-
ing system checked for signs of leakage).
Please make sure the mixture is in accor-
dance with label instructions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you
are not sure about the water quality, con-
sult your authorized Mercedes-Benz Light
Truck Center.

305 Technical data
Fuels, coolants, lubricants etc.
Anticorrosion / antifreeze
Your vehicle contains a number of alumi-
num parts. The use of aluminum compo-
nents in motor vehicle engines
necessitates that
anticorrosion / antifreeze coolant used in
such engines be specifically formulated to
protect the aluminum parts. (Failure to use
such anticorrosion / antifreeze coolant will
result in a significantly shortened service
life.)
Therefore, the following product is strongly
recommended for use in your vehicle:
Mercedes-Benz Anticorrosion / Antifreeze
agent.
Before the start of the winter season (or
once a year in hot southern regions), you
should have the anticorrosion / antifreeze
concentration checked. The coolant is also
regularly checked each time you bring your
vehicle to your authorized Mercedes-Benz
Light Truck Center for service.

307 Technical data
Fuels, coolants, lubricants etc.
Windshield washer system and headlamp cleaning system*
Both the windshield washer and headlamp
cleaning system* are supplied from the
windshield washer fluid reservoir.
The windshield and headlamp washer fluid
reservoir has a capacity of approx.
8.0 US qt (7.6 l).
Refill the reservoir with MB Windshield
Washer Concentrate “S” and water (or
concentrate and commercially avail-
able premixed windshield washer
solvent / antifreeze, depending on am-
bient temperatures).Windshield and headlamp washer fluid
mixing ratio
For temperatures above freezing, use
MB Windshield Washer Concentrate “S”
and water:

1 part “S” to 100 parts water
[40 ml “S” to 1 gallon (4 liters) water].
For temperatures below freezing, use
MB Windshield Washer Concentrate “S”
and commercially available premixed
windshield washer solvent / antifreeze:


1part “S” to 100parts solvent
[40 ml “S” to 1 gallon (4 liters) solvent].
Warning!
G
Washer solvent / antifreeze is highly flam-
mable. Do not spill washer
solvent / antifreeze on hot engine parts, be-
cause it may ignite and burn. You could be
seriously burned.

311 Technical terms
ABS
(A
ntilock B
rake S
ystem)
Prevents the wheels from locking up
during braking so that the vehicle can
continue to be steered.
BabySmart
TM airbag deactivation
system
This system detects if a special system
compatible child restraint seat is in-
stalled on the front passenger seat. The
system will automatically deactivate
the passenger front airbag when such a
seat is properly installed (indicator
lamp7 in the instrument cluster
lights up). See your authorized
Mercedes-Benz Light Truck Center for
availability.
BabySmartTM compatible child seats
Special restraint system for children.
The sensor system for the passenger
seat prevents deployment of the pas-
senger front airbag if a BabySmart
TM
compatible child seat is installed.BAS
(B
rake A
ssist S
ystem)
System for potentially reducing braking
distances in emergency braking situa-
tions. The system is activated when it
senses an emergency based on how
fast the brake is applied.
Bi-Xenon headlamps*
Headlamps which use an electric arc as
the light source and produce a more in-
tense light than filament headlamps.
Bi-Xenon headlamps produce low
beam and high beam.
CAC
(C
ustomer A
ssistance C
enter)
Mercedes-Benz customer service cen-
ter, which can help you with any ques-
tions about your vehicle and provide
assistance in the event of a break-
down.CAN system
(C
ontroller A
rea N
etwork)
Data bus network serving to control ve-
hicle functions such as door locking or
windshield wiping.
Cockpit
All instruments, switches, buttons and
indicator / warning lamps in the pas-
senger compartment needed for vehi-
cle operation and monitoring.
Cruise control
Driving convenience system for auto-
matically maintaining the vehicle speed
set by the driver.
Engine number
The number set by the manufacturer
and placed on the cylinder block to
uniquely identify each engine pro-
duced.

312 Technical termsEngine oil viscosity
Measurement for the inner friction (vis-
cosity) of the oil at different tempera-
tures. The higher the temperature an
oil can tolerate without becoming thin,
or the lower the temperature it can tol-
erate without becoming viscous, the
better the viscosity.
ESP
(E
lectronic S
tability Pr
ogram)
Improves vehicle handling and direc-
tional stability.
ETD
(E
mergency T
ensioning D
evice)
Device which deploys in certain frontal
and rear collisions exceeding the sys-
tem's threshold to tighten the seat
belts.
->SRSFSS
(F
lexible S
ervice S
ystem)
Service indicator in the speedometer
display that informs the driver when
the next vehicle maintenance service is
due.
Gear range
Number of gears which are available to
the automatic transmission for shifting.
The automatic gear shifting process
can be adapted to specific operating
conditions using the gear selector
lever.
GPS
(G
lobal P
ositioning S
ystem)
Satellite-based system for relaying
geographic location information to and
from vehicles equipped with special re-
ceivers. Employs CD or DVD digital
maps for navigation.GAWR
(G
ross A
xle W
eight R
ating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight
on each axle must never exceed the
GAWR for the front and rear axle indi-
cated on the certification label located
on the driver’s door pillar.
GVW
(G
ross V
ehicle W
eight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare
wheel, installed accessories, passen-
gers and cargo. The GVW must never
exceed the GVWR, indicated on the
certification label located on the driv-
er’s door pillar.

313 Technical terms
GVWR
(G
ross V
ehicle W
eight R
ating)
This is the maximum permissible vehi-
cle weight. It is indicated on certifica-
tion label located on the driver’s door
pillar.
Instrument cluster
The displays and indicator / warning
lamps in the driver’s field of vision, in-
cluding the tachometer, speedometer,
engine temperature and fuel gauge.
Kickdown
Depressing the accelerator past the
point of resistance shifts the transmis-
sion down to the lowest possible gear.
This very quickly accelerates the vehi-
cle and should not be used for normal
acceleration needs.Line of fall
The direct line that an object moves
downhill when influenced by the force
of gravity alone.
Lock button
Button on the door which indicates
whether the door is locked or un-
locked. Pushing the lock button down
on an individual door from inside will
lock that door.
MCS
(M
odular C
ontrol S
ystem)
Information and operating center for
vehicle sound and communications
systems, including the radio and the ra-
dio and navigation system, as well as
for other optional equipment (CD
changer, telephone, etc.).Memory function*
Used to store three individual seat,
steering wheel and mirror positions.
MON
(M
otor O
ctane N
umber)
The Motor Octane Number for gasoline
as determined by a standardized meth-
od. It is an indication of a gasoline's
ability to resist undesired detonation
(knocking). The average of both the
MON (Motor Octane Number) and
->RON (Research Octane Number) is
posted at the pump, also known as
ANTI-KNOCK INDEX.
Multifunction display
A display field in the instrument cluster
used to present information provided
by the control system.
Parktronic system* (Parking assist)
System which uses visual and acoustic
signals to assist the driver during park-
ing maneuvers.

314 Technical termsPoly-V-belt drive
Drives engine-components (alternator,
AC compressor, etc.) from the engine.
Power train
Collective term designating all compo-
nents used to generate and transmit
motive power to the drive axles, includ-
ing


engine


clutch / torque converter


transmission


transfer case


drive shaft


differential


axle shafts / axlesRemote Vehicle Diagnostics
Transmission of vehicle data and cur-
rent location to the Mercedes-Benz
Customer Assistance Center for sub-
scribers to Tele Aid service.
REST
(Residual engine heat utilization)
Feature that uses the engine heat
stored in the coolant to heat the vehi-
cle interior for a short time after the en-
gine has been turned off.
Restraint system
Seat belts, belt tensioner, airbags and
child seat restraint systems. As inde-
pendent systems, their protective func-
tions complement one another.RON
(R
esearch O
ctane N
umber)
The Research Octane Number for gaso-
line as determined by a standardized
method. It is an indication of a gaso-
line's ability to resist undesired detona-
tion (knocking). The average of both
the ->MON (Motor Octane Number)
and RON (Research Octane Number) is
posted at the pump, also known as
ANTI-KNOCK INDEX.
Shift lock
When the vehicle is parked, this lock
prevents the transmission selector le-
ver from being moved out of positionP
without key turned and brake pedal de-
pressed.
SRS
(S
upplemental R
estraint S
ystem)
Seat belts, emergency tensioning de-
vice and airbags. Though independent
systems, they are closely interfaced to
provide effective occupant protection.

317 Index
A
ABS 25, 76, 311
ABS control 76
LOW RANGE mode 77
Malfunction indicator lamp 242
Warning lamp 242
Accelerator position, automatic
transmission 123
Accident
In case of 52
Activating
Air circulation mode 139
Air recirculation mode 139
Anti-theft alarm system 83
Automatic climate control 135
ESP 82
Exterior headlamps 48
Hazard warning flasher 112
Headlamps 48
High beams 110
Ignition 33Immobilizer 54, 83
Rear passenger compartment ventila-
tion and climate control 141
Rear window defroster 133
Rear window wiper 51
Residual heat 140
Seat heater* 98
Tow-away alarm 85
Warning indicators (Parktronic*) 155
Windshield wipers 50
Activating automatic central locking 93
Adding
Coolant 223
Engine oil 221
Additional turn signals 266
Adjustable steering column
Indicator lamp 253
Adjusting 34
Backrest tilt 36, 38
Exterior rear view mirror 40
Head restraint height 36, 38Head restraint tilt 37, 39
Headlamp aim 272
Instrument cluster illumination 116
Manual seat 35
Mirrors 40
Power seats* 37
Seat cushion tilt 38
Seat fore and aft 35
Seat fore and aft adjustment 37
Seat height 36, 38
Seats 34
Steering wheel 39
Adjusting air distribution
Automatic climate control 137
Adjusting air volume
Automatic climate control 137
Air conditioner (cooling)
Turning on 139
Air conditioning
Cooling 139