engine MERCEDES-BENZ ML320 1997 Complete Repair Manual

234
Engine compartment
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
Automatic transmission fluid level
The transmission has a permanent fill of automatic
transmission fluid.
Regular automatic transmission fluid level checks and
changes are not required. For this reason the dipstick is
omitted.
If you notice fluid leaks or gear shifting malfunctions,
have your authorized Mercedes-Benz Light Truck Center
check the transmission fluid level.
Engine oil consumption
Engine oil consumption checks should only be made
after the break-in period. During the break-in period,
higher oil consumption may be noticed and is normal.
Frequent driving at high engine speeds results in
increased consumption. Coolant level
To check the coolant level, the vehicle must be parked
on level ground and the engine stopped.
Check coolant level only when coolant is cold.
The coolant level should reach the COLD LEVEL mark in
the reservoir.P20.30-0241-20

235
Engine compartment
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
Adding coolant
If coolant has to be added, a 50 / 50 mixture of water and
MB anticorrosion / antifreeze should be added.
After adding coolant, close cap until you hear it click a
few times.
The drain plugs for the cooling system are located on
the left and right side of the engine block directly above
the engine mounts and at the bottom of the radiator.
Anticorrosion / antifreeze mixture, see page 297.
Wa r n i n g !
In order to avoid possible serious burns or injury: • Use extreme caution when opening the hood if there are any signs of steam or coolant leaking
from the cooling system, or if the coolant
temperature gauge indicates that the coolant is
overheated.
• Do not remove pressure cap on coolant reservoir if engine temperature is above 194 °F
(90 °C). Allow engine to cool down before
removing cap. The coolant reservoir contains
hot fluid and is under pressure.• Using a rag, slowly open cap approximately 1/2 turn to relieve excess pressure. If opened
immediately, scalding hot fluid and steam will
be blown out under pressure.• Do not spill antifreeze on hot engine parts. Antifreeze contains ethylene glycol which may
burn if it comes into contact with hot engine
parts.

236
Engine compartment
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
Windshield washer/headlamp cleaning system
The reservoir should be refilled with MB Windshield
washer concentrate and water (or commercially
available premixed windshield washer solvent/
antifreeze, depending on ambient temperatures).
1 Windshield washer / headlamp cleaning / rear
window wiper / washer system fluid reservoir
Vehicles without headlamp cleaning system:
Capacity approximately 5.3 US qt (5.0 l).
Vehicles with headlamp cleaning system:
Capacity approximately 8.0 US qt (7.6 l).
Wa r n i n g !
Washer solvent / antifreeze is highly flammable. Do
not spill washer solvent / antifreeze on hot engine
parts, because it may burn. You can be seriously
burned.

246
Tires, Wheels
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
Move vehicle to a level area which is a safe distance
from the roadway.
Important!
The vehicle doors lock if the left front wheel rotates with
the engine running. Do not leave the engine running
while changing a wheel.
1. Set parking brake and turn on hazard warning flasher.
2. Move selector lever to position “P” and turn off engine, and remove key from the steering lock.
3. Prevent vehicle from rolling away by blocking wheels with wheel chocks (not supplied with
vehicle) or sizable wood block or stone. When
changing a wheel on a hill, place chocks on the
downhill side blocking both wheels of the other
axle. On a level road, place one chock in front of and
one behind the wheel that is diagonally opposite to
the wheel being changed. 4. Using the wrench, loosen but do not yet remove the
wheel bolts.
5. Open jack enough to fit under vehicle.
The jack take-up brackets are located directly
behind the front wheel housings and in front of the
rear wheel housings.
P40.10-2370-26

247
Tires, Wheels
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
6. Place jack on firm ground. Position the jack under
t he take-up bracket so t hat it is always ve rtical
(plumb-line) as seen from the side, even if the
vehicle is parked on an incline.
7. Open jack further until jack arm end seats firmly in the take-up bracket and its base sits sq uarely on the
ground. Jack up the vehicle until the wheel is clear
of the ground. Never start engine while vehicle is
raised. 8. Unscrew and remove all wheel bolts. Keep bolt
threads protected from dirt and sand.
9. Remove wheel. Grip wheel from the sides. Keep hands from beneath the wheels.
Clean contact surfaces of wheel and wheel hub.
Install spare wheel on wheel hub. Insert wheel bolts
and tighten them slightly.
10. Lower vehicle to ground. Remove jack.
Before storing the jack, it should be fully collapsed, with
handle folded in.
For proper storage of jack see page 237.

249
Tires, Wheels
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
Inflating the space-saver tire
(ML 55 AMG only)
1. Remove air pump from compartment behind the space-saver spare wheel.
2. Open lid (arrow) and pull out filler hose (1) with pressure gauge and electrical plug (2). Observe
manufacturer’s instructions.
3. Unscrew tire valve cap from space-saver tire valve.
4. Screw filler hose (1) onto space-saver tire valve. 5. Plug air pump electrical plug (2) into electrical
outlet in front passenger footwell or rear cargo
compartment.
6. Start the engine and switch on the air pump.
7. Operate air pump (approximately 8 minutes) until pressure gauge displays 61 psi (4.2 bar).
8. Switch off air pump and turn off the engine.
9. Unscrew filler hose from space-saver tire. Reinstall tire valve cap.
Note:
Excessive tire air pressure should be released using the
vent screw.
3
12
Wa r n i n g !
When working on the vehicle with the engine
running, always set the parking brake in addition
to shifting the gear selector lever to position “P”.Wa r n i n g !
To prevent possible injury when unscrewing air
pump filler hose from space-saver tire valve after
inflating the tire, use a rag since the tire valve
could be hot.

251
Battery
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
If a tire constantly loses air, it should be inspected for
damage.
The spare tire should be checked periodically for
condition and inflation. Spare tire will age and become
worn over time even if never used, and thus should be
inspected and replaced when necessary. Battery
Important!
Battery replacement information:
The maintenance-free battery is located in the engine
compartment.
The service life of the battery is dependent on its
condition of charge. The battery should always be kept
sufficiently charged, in order to last an optimum length
of time.
Wa r n i n g !
Do not overinflate tires. Overinflating tires can
result in sudden deflation (blowout) because they
are more likely to become punctured or damaged
by road debris, potholes etc.. Follow recommended
inflation pressures.Do not overload the tires by exceeding the specified
vehicle capacity weight (as indicated by the label
on the driver’s door latch post). Overloading the
tires can overheat them, possibly causing a
blowout.
Wa r n i n g !
Failure to follow these instructions can result in
severe injury or death.Never lean over batteries while connecting, you
might get injured.Battery fluid contains sulfuric acid. Do not allow
this fluid to come in contact with eyes, skin or
clothing. In case it does, immediately flush affected
area with water and seek medical help if necessary.A battery will also produce hydrogen gas, which is
flammable and explosive. Keep flames or sparks
away from battery, avoid improper connection of
jumper cables, smoking etc..

252
Battery
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
Therefore, we strongly recommend that you have the
battery charge checked frequently, and corrected if
necessary, especially if you use the vehicle less than
approximately 200 miles (300 km) per month,
mostly for short distance trips, or if it is not used for
long periods of time.
Only charge a battery with a battery charger after the
battery has been disconnected from the vehicle’s
electrical circuit.
Always disconnect the battery negative lead first and
connect last.
When removing and connecting the battery, always
make sure that all electrical consumers are off and the
key is in steering lock position 0. The battery must
always be securely installed when the vehicle is in
operation. During removal and installation always
protect the disconnected battery positive (+) terminal
with the cover attached to the battery.
While the engine is running the battery terminal clamps
must not be loosened or detached, otherwise the
generator and other electronic components would be
damaged. Note:
After reconnecting the battery also set the clock in
instrument cluster (see page 80), set date in trip
computer (see page 83), resynchronize the sliding / pop-
up roof (see page 272), the Skyview Top (see page 273)
and the electronic stability program (ESP) (see
page 206).
Battery recycling
Batteries contain material that can harm the
environment with improper disposal.
Large 12 Volt storage batteries contain lead.
Recycling of batteries is the preferred method of
disposal.
Many states require sellers of batteries to accept old
batteries for recycling.

253
Jump starting
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
Jump starting
Important!
A discharged battery can freeze at approximately +14 °F
(–10 °C). In that case, it must be thawed out before
jumper cables are used. Attempting to jump start a
frozen battery can result in it exploding, causing
personal injury.
Jumper cable specifications:
• Minimum cable cross-section of 25 mm
2 or
approximately 2 AWG
• Maximum length of 11.5 ft. (3.5 m).
If the battery is discharged, the engine should be started
with jumper cables and the (12 V) battery of another
vehicle.
Only use 12 V battery to jump start your vehicle. Jump
starting with more powerful battery could damage the
vehicle’s electrical systems, which will not be covered
by the Mercedes-Benz Limited Warranty.
The battery is located in the engine compartment.
Wa r n i n g !
Failure to follow these directions will cause
damage to the electronic components, and can lead
to a battery explosion and severe injury or death.Never lean over batteries while connecting or jump
starting, you might get injured.Battery fluid contains sulfuric acid. Do not allow
this fluid to come in contact with eyes, skin or
clothing. In case it does, immediately flush affected
area with water, and seek medical help if
necessary.A battery will also produce hydrogen gas, which is
flammable and very explosive. Keep flames or
sparks away from battery, avoid improper
connection of jumper cables, smoking etc..Read all instructions before proceeding.

254
Jump starting
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
Proceed as follows: 1. Position the vehicle with the charged battery so that the jumper cables will reach, but never let the
vehicles touch. Make sure the jumper cables do not
have loose or missing insulation.
2. On both vehicles: • Turn off engine and all lights and accessories,
except hazard warning flashers or work lights.
• Apply parking brake and shift selector lever to
position “P”.
Important!
3. Clamp one end of the first jumper cable to the positive (+) under hood terminal of the discharged
battery and the other end to the positive (+) terminal
of the charged battery. Make sure the cable clamps
do not touch any other metal parts.
4. Clamp one end of the second jumper cable to the grounded negative (–) terminal of the charged
battery and the final connection to the negative (–)
terminal of the discharged battery. Important!
5. Start engine of the vehicle with the charged battery and run at high idle. Make sure the cables are not
on or near pulleys, fans, or other parts that move
when the engine is started. Allow the discharged
battery to charge for a few minutes. Start engine of
the disabled vehicle in the usual manner.
6. After the engine has started, remove jumper cables by exactly reversing the above installation
sequence, starting with the last connection made
first. When removing each clamp, make sure that it
does not touch any other metal while the other end
is still attached.
Notes:
If engine does not run after several unsuccessful
starting attempts, have it checked at the nearest
authorized Mercedes-Benz Light Truck Center.
Excessive unburned fuel may damage the catalytic
converter.