Mercedes-Benz 300SD 1981 User manual

Drive Sensibly — Save Fuel
Fuel consumption depends to a great
extent on driving habits and operating
conditions.
In order to save fuel you should:
ensure that tire pressures are
correct
not carry unnecessary loads
remove ski racks or roof-mounted
luggage racks when not in use
not warm up your engine at idle
and with the vehicle at standstill
avoid frequent acceleration and
deceleration
avoid frequent braking
avoid unnecessarily high speeds
have all the maintenance jobs
specified by us carried out at
regular intervals by a
MERCEDES-BENZ service station.
Driving in low temperature weather, in
stop-and-go city traffic and on short
hops, and in hilly country also
increases fuel consumption.

300SD
Type 126 D
1981

You have chosen to drive a MERCEDES-BENZ, a car in whose construction
and production we have taken great pains because we believe that quality is
not a matter of chance.
Perhaps you have already had experience with a MERCEDES, maybe this is
your first car from the DAIMLER-BENZ company. In both cases — for your
own benefit — please read this owner’s manual before putting it away. Even
though you have been driving a car for years, some things in this car may be
new to you, and this manual certainly contains a few hints which will help you
to make the most of your new car.
We wish you safe and pleasant motoring.
DAIMLER-BENZ Aktiengesellschaft
3

This Owner's Manual also describes
optional extras as far as this is
required for their operation.
/4s the scope of delivery is deter
mined by the order the equipment of
your vehicle may deviate from the
descriptions and illustrations to some
extent.
Vehicle Operation
Instruments and Controls .
Instrument Cluster ............
Keys, Doors ......................
Master Key and
Supplementary Key
Flat Key ..........................
Obtaining Replacement
Keys ..............................
Opening, Locking and
Unlocking of Doors
Master Lock System .. .
Seats ...................................
Electrical Adjustment of
Driver’s and Front
Passenger’s Seats ........
Safety Headrests ..........
Orthopaedic Seat Back .
Arm Rest (Front Seats) .
Arm Rest (Rear Seat) . .
Seat Heater ..................
Safety Belts ..................
The last page
What you should know at the gas
station
Contents
Controls ....................................... 22
Steering Lock ........................... 22
Lighting Switch ....................... 23
12 Combination Switch ............... 24
14 Cruise Control .......................... 25
Automatic Climate Control 26
^ Various Equipment ..................... 28
Exterior M irrors ....................... 28
Inside Rear View Mirror 28
Sun Visors ............................... 29
Sliding R oof ............................. 29
Interior Lam ps ......................... 30
Heated Rear Window .............. 30
16 Electric Lighter .......................... 31
Shelf below Rear Window .... 31
Electric Window Lifters 31
I® Radio .............................................. 32
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18
19
19
20
5

Contents
Driving
Hood ............................................. 42
Regular Inspections .................... 43
Parking Brake .............................. 44
Starting and Turning
off the Engine ............................... 44
Starting and Shifting Gears 46
Safe Driving ................................. 48
Brake Pad Wear Indicator
Lamp ......................................... 50
Brake Fluid ............................... 50
Charge Indicator Lam p 50
Oil Pressure Gauge ................ 50
Coolant Temperature Gauge 50
Emission Control ..................... 51
Engine Oil Consumption 51
The First 1500 km/1000 Miles ... 51
Special Operating Conditions... 52
Winter Driving .......................... 52
Hints for Driving ...................... 52
High Altitude Correction
Device ....................................... 53
Tire Chains ............................... 53
Traveling Abroad .................... 53
Vehicle Care
MERCEDES-BENZ Maintenance
System ......................................... 56
Severe Operating Conditions 56
Enginge Oil Change and Filter
Change ..................................... 57
Automatic Transmission —
Fluid and Filter Change 57
Spare Parts Service .................... 57
Cleaning and Care of the Vehicle 58
Jobs related to C are .............. 59
Practical Hints
Ash trays ..................................... 62
Rear Seat Cushion ...................... 62
Bleeding the Fuel System 63
Turning off Engine Manually .... 63
First Aid Kit ................................... 64
Luggage or Ski Racks ................ 64
Spare Wheel, Jack,
Vehicle Tool Kit .......................... 64
Wheels, Tires, Changing Wheels 65
Wheels, Tires .......................... 65
Changing Wheels ..................... 66
Tire Inflation Pressure 67
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Contents
Checking Fuels, Coolants,
Lubricants, etc
.............................. 68
Engine Oil Level Check 68
Checking Coolant Level
........ 69
Replenishing Coolant ............ 69
Fluid Level —
Automatic Transmission 70
Electrical System ......................... 71
Fuses
....................................... 71
Battery
..................................... 71
Replacing Bulbs ....................... 72
Windshield Wipers
....................... 75
Emergency Operation of
Sliding R oof ................................. 75
Unlocking the Fuel Filler Flap ... 75
Jump Starting ............................... 76
Tow-starting and Towing
the Vehicle ................................... 76
Technical Data, Fuels, Coolants,
Lubricants, etc.
Identification Plates ..................... 80
Vehicle Data Cards ..................... 81
Warranty Coverage ..................... 81
Technical Data
............................. 82
Fuels, Coolants, Lubricants, etc. 84
Capacities ................................. 84
Engine Oils ............................... 86
Brake Fluid ............................... 86
Diesel Fuels ............................. 87
Coolants ................................... 88
Service Literature
......................... 89
Vehicle Operation
Driving
Vehicle Care
Practical Hints
Technical Data, Fuels,
Coolants, Lubricants, etc.
7

Vehicle Operation

Instruments and Controls
For more detailed descriptions see quoted pages.
B 1 Speaker grilles
2 Side ventilation outlets (page 26)
3 Swivelling outlets for nonheated fresh air (page 26)
4 Parking brake release handle (page 44)
5 Handle to disengage hood lock (page 42)
6 Parking brake pedal (page 44)
7 Combination switch (page 24)
8 Lighting switch (page 23)
9 Cruise control (page 25)
10 Instrument cluster (page 12)
11 Horn control
12 Steering lock (page 22)
Steering lock with preglow/starter switch
13 Lever for nonheated fresh air (page 26)
10
14 Switch for rear passenger compartment lamp
(page 30)
15 Switch for electric sliding roof (page 29)
16 Switch for hazard warning flasher system
17 Switch for automatic antenna (page 34)
18 Switch for heated rear window (page 30)
19 Automatic climate control (page 26)
20 Radio (page 32)
21 Ash tray with lighter (page 31, 62)
22 Switch for left front seat heater (page 19)
23 Loudspeaker — fader control
24 Switch for right front seat heater (page 19)
25 Switch group for window lifters (page 31)
26 Adjusting lever for exterior mirror on front
passenger side (page 28)
27 Glove compartment, illuminated (only in steering
lock positions “ 1 ” or “2”)

Instruments and Controls
11

Instrument Cluster
1 Coolant temperature gauge (° C)
Up to red marking: Maximum permissible
temperature for an antifreeze-blended fill protecting
down to - 30° C/ - 22° F. See page 50.
2 Fuel gauge with reserve warning lamp (yellow)
Fuel reserve and capacity, refer to page 85 and last
page.
3 Oil pressure gauge (bar). See page 50.
4 Turn signal indicator lamp, left (green)
5 Main odometer
6 Trip odometer
7 Turn signal indicator lamp, right (green)
8 Tachometer
9 Electric clock
10 Knob for clock adjustment
(press in for adjustments)
11 Seat belt warning lamp (red)
12 Preglow indicator lamp (yellow)
13 Brake warning lamp (red) comes on if
the parking brake is engaged
not enough brake fluid is in the reservoir
14 Brake pad wear indicator lamp (yellow):
Lights up during braking if the front wheel brake pads
are worn down. See page 50.
15 Charge indicator lamp (red):
Comes on when the steering lock key is moved to
driving position “2” and must go out when the
engine is idling. See page 50.
16 High beam indicator lamp (blue)
17 Knob for instrument lamps and trip odometer
Rotate knob: instrument lamps intensity are
infinitely variable
Depress knob: trip odometer is turned back
Note
A stop is provided on the speedometer at the
138 km/h/85 mph reading. Speeds in excess of
138 km/h/85 mph will not be indicated.

Instrument Cluster
13

Keys Doors
Master Key — square head -
locks on the car. -fits all Flat Key
Supplementary Key— rounded head
— fits only the door locks and the
steering lock. This key is intended to
be used whenever the car is left with
an attendant. Be sure to lock glove
compartment and trunk with the
master key.
The flat key fits all vehicle
locks. We recommend that
you carry the flat key with
you and keep it in a safe
place so that it is always
handy, if needed (e.g. in
your wallet). Never leave the flat key in
the vehicle.
Obtaining Replacement Keys
Replacement keys can be obtained
only via MERCEDES-BENZ service
stations. If the keys are lost, assist
ance is rather time consuming and
expensive.
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Keys Doors
Opening t e Doors
From outside: pull handle outwards (1)
From inside: pull handle in door trim
panel (4).
4
Locking and Unlocking of Doors
From the outside: turn key.
From the inside: actuate plunger.
2 Unlocking
3 Locking
When the rear door plungers are
pushed down, the rear doors cannot
be opened from the outside or the
inside. They can be opened after
pulling plungers up.
One cannot lock:
the driver’s door if it is open.
any door if the door lock has not
engaged fully. In this case open
the door and close it again.
15

Keys Doors Seats
>
Master Lock System
The master lock system locks or
unlocks the driver’s door, the other
vehicle doors, the fuel tank filler flap
and the trunk lid simultaneously. The
lock plungers of the other vehicle
doors must then move together with
the lock plunger of the driver’s door.
If this does not happen, the lock of
the respective door is not properly
engaged. Open the door again and
shut it correctly.
The front passenger door and the rear
doors can also be locked or unlocked
individually from inside. The front
passenger door can also be locked
and unlocked with the key.
With the master lock system in the
locked position, the trunk lid can also
be unlocked individually: To do so,
turn the main key to the left as far as it
will go, then depress the trunk lid lock
push button with the key and open
the trunk. Turn the key to its initial
position and withdraw it. To lock the
trunk lid, close it firmly; the trunk lid
will then be locked by the master lock
system again.
The trunk lid can also be locked
independently (for instance, to leave
the vehicle in a workshop) without
actuating the master lock system.
Turn the main key to the right as far as
it will go and withdraw it. In this case
the trunk lid can only be unlocked
with the main key which must be
inserted and turned back to the left.
Note:
If the fuel tank filler flap cannot be
opened, refer to “ Unlocking the Fuel
Filler Flap” (page 75).
Electrical Adjustment of Driver’s and
Front Passenger's Seats
Turn key in steering lock to
position “2” .
Seat and seat back can be adjusted
individually by means of the switches.
These are accommodated in the front
doors.
When the key is withdrawn or turned
to steering lock positions “ 1” or “0",
seat and seat back can be adjusted
only if the driver's door is open.
16

Seats
Note:
Prior to operating the vehicle, the
driver should adjust the seat height
for proper vision as well as fore-aft
placement and seat back angle to
insure adequate control, reach, oper
ation, and comfort. The headrest
should also be adjusted for proper
height so that when the cushion is
tipped completely forward, it should
form a cradle behind the seat
occupant’s head. Both the inside and
outside rear view mirrors should then
be adjusted for adequate rearward
vision. Fasten seat belts. Children
under the age of six or under the
weight of 23 kg/50 lb should be
seated in the back seat with an
approved restraint system properly
secured.
All seat, headrest, and rear view
mirror adjustments as well as fasten
ing of seat belts should be accom
plished before the vehicle is put into
motion.
Safety Headrests
Adjust headrest to support the back
of the head approximately at ear level.
Safety headrests, front
Height adjustment:
Press headrest slightly forward (1)
and reset upward or downward as
required.
Detaching headrests:
Pull headrest out to the stop. Release
arrester by depressing release knob
to be felt under the seat back
covering material and pull headrest
upward quickly, holding it by the LH
headrest post (viewed in driving
direction). Then pull out headrest
completely with both hands.
The headrest release knob is located
below the LH headrest post (2).
Safety headrests, rear
Height adjustment:
Raise or lower headrest as required.
Detaching headrests:
Pull up headrest until resistance can
be felt. Then pull it out quickly using
both hands.
17

Seats
>
Ort opaedic Seat Back
Turn handwheel (1) to adjust the
spinal support. The spinal support
must not be inflated when being
adjusted. A red mark in window (2)
indicates the height it is adjusted to.
To inflate the spinal support, actuate
hand pump (3) as required. For
deflation, push button (4).
Arm Rest (Front Seats)
The arm rest engages in 3 positions.
Position 1 = arm rest folded up.
Position 2 = for normally inclined
seat back.
Position 3 = for extremely inclined
seat back.
For downward adjustment of the arm
rest, depress release button 4.
Note:
The arm rest does not suffice as a
child restraint system. In case of a
frontal collision a child can be
catapulted forward over the locked
arm rest. It is only suitable as
protection against objects which
might be hurled forward when the
vehicle is decelerated.
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