Lawn Tractor 8211 0276 01 Stiga Park Pro20 Pro18 Pro16 Royal President Senator Operators Manual

							ENGLISHGB
START AND OPERATING
ENGINE CASING
To inspect and maintain the engine and battery, re-
move the engine casing as follows:
1. Unscrew the fuel cap/fuel gauge.
2. Carefully lift off the engine casing (fig. 10).
Assembly:
1. Make sure that the front part of the casing fits
into the track in the U-shaped attachment on the
machine (fig. 11).
2. Place the casing over the lip on each side
(fig. 11).
3. Make sure that the pins on the back edge of the
casing go down into the respective holes (fig. 12).
4. Finally, screw in the fuel cap/fuel gauge.
Do not use the machine without first fit-
ting the engine casing, otherwise there
is a risk of burn injuries or crushing ac-
cidents.
FILLING THE FUEL TANK
Always use lead-free petrol. Never use oil-mixed
petrol.
NOTE! Bear in mind that petrol is a perishable; do
not purchase more petrol than can be used within
thirty days.
Environmentally friendly petrol can be used. This
type of petrol has a composition that is less hazard-
ous for people and nature.
Petrol is highly inflammable. Always
petrol in containers that are made espe-
cially for this purpose.
Only fill or top up with petrol outdoors,
and never smoke when filling or top-
ping up. Fill with petrol before starting
the engine. Never remove the filler cap
or fill with petrol while the engine is
running or still warm.
Never completely fill the fuel tank. Leave an emp-
ty space (= at least the entire filler tube plus 1 - 2
cm at the top of the tank) to allow the petrol to ex-
pand when it warms up without overflowing (fig.
28).
CHECKING THE ENGINE OIL LEVEL
On delivery, the crankcase is filled with SAE 30
oil.
Check the oil level every time before using to
ensure that it is correct. The machine should be
standing on level ground.
Wipe clean round the oil dipstick, remove
it and wipe off. Push down the dipstick
fully and screw it back in.
Then unscrew it and pull it up again. Read off the
oil level. Top up with oil to the “FULL” mark, if
the level comes below it (figs. 13 - 15).
CHECKING THE TRANSMISSION
OIL LEVEL (Pro16- Pro18 - Pro20)
The transmission is filled with SAE 10W-40 oil
when the machine is delivered from the factory,
Check the oil level every time before using to
ensure it is correct. The machine should be
standing on level ground.
Read off the oil level in the reservoir (fig. 29). It
should be between the MAX and MIN marks. If
necessary, top up with SAE 10W-40 (20W-50) oil.
SAFETY SYSTEM
This machine is equipped with a safety system that
consists of:
- a switch on the gearbox (only Senator).
- a switch at the brake pedal.
- a switch in the seat mounting (Senator, Presi-
dent) or the seat bracket (other models).
- a switch at the power take-off engagement.
In order to start the machine, the following are nec-
essary:
- gear lever in neutral (only Senator).
- brake pedal pressed down.
- driver sitting on seat.
- power take-off engagement lever at lowest set-
ting (i.e. power take-off disengaged).
Always check the operation of the safe-
ty system before using the machine!
With the engine operating and the driver sitting on
the seat, check in the following way:
- select a gear, lift your weight off the seat – the
engine must stop (applies to Senator).
- press the drive pedal so that the machine starts
to move, release the drive pedal – the machine 
						

							ENGLISHGB
must stop (applies to President, Royal, Pro16,
Pro18, Pro20).
- press the drive pedal so that the machine starts
to move, engage the cruise control, lift your
weight off the seat – the machine must stop (ap-
plies to Royal, Pro16, Pro18, Pro20).
- press the drive pedal so that the machine starts
to move, engage the cruise control, press the
brake pedal – the machine must stop (applies to
Royal, Pro16, Pro18, Pro20).
- engage the power take-off, lift your weight off
the seat – the engine must stop (applies to Sen-
ator, President, Royal, Pro16).
- engage the power take-off, lift your weight off
the seat, the power take-off must be disengaged
(applies to Pro18, Pro20).
Do not use the machine if the safety sys-
tem does not work! Take the machine to
a service agent for inspection!
STARTING ENGINE
1. Open the fuel cock (fig. 16).
2. Make sure that the sparking plug cable is prop-
erly in place.
3. Check to make sure that the power take-off is
disengaged.
4a. Senator:
Put the gear lever in neutral
4b. President-Royal-Pro16-Pro18-Pro20:
Do not keep your foot on the drive pedal.
5a. Senator-President:
Starting cold engine – put the throttle control in the
choke position. Starting warm engine – put the
throttle control at full throttle (approx. 1 cm behind
the choke position).
5b. Royal-Pro16-Pro18-Pro20:
Put the throttle control at full throttle. Starting cold
engine – pull the choke control out fully. Starting
warm engine – do not touch the choke control.
6. Depress the brake pedal fully.
7. Turn the starter key and start the engine.
8a. Senator-President:
Once the engine has started, move the throttle con-
trol gradually to full throttle if the choke has been
used.
8b. Royal-Pro16-Pro18-Pro20:
Once the engine has started, push the choke control
in gradually if it has been used.9. When starting from cold, do not make the ma-
chine work under load immediately, but let the en-
gine run for some minutes first. This will allow the
oil to warm up.
When in use, always operate the engine at full
throttle.
STOPPING
Disengage the power take-off and apply the park-
ing brake.
Allow the engine to idle 1 - 2 mins. Stop the engine
by turning off the ignition key.
Shut off the petrol cock. This is particularly impor-
tant if the machine is to be transported on a trailer
for example.
If the machine is left unattended, re-
move the lead from the spark plug. Also
remove the starter key.
The engine may be very warm immedi-
ately after it is shut off. Do not touch the
silencer, cylinder or cooling flanges as it
can cause burns and injury.
CATALYTIC CONVERTER (Pro18 -
Pro20)
The catalytic converter gets very hot during opera-
tion. The heat remains for a long time after the en-
gine has been stopped. Be aware of fire risk.
Do not park in close proximity to in-
flammable objects. Do not cover the
machine until the catalytic converter
has cooled down.
STEERING AID (Pro20)
Built-in function in order to facilitate steering. The
operator only has to turn the steering wheel gently.
An hydraulic torque amplifier creates the remain-
ing force.
As opposed to a normal servo steering (e.g. in a
car), the steering aid has a limited capacity. This
means that it has some characteristics that might be
considered negative:
- at a low engine rpm or in situations where extra
steering force is needed, steering can be consid-
ered to be “jumpy”.
- the machine should always be moving when the
steering is used. Avoid turning the steering
wheel when the machine stands completely still
and the accessory is in the lowered working po- 
						

							ENGLISHGB
sition.
The steering is adapted in order to produce better
results at a normal working speed.
Even when the engine is not running, the steering
works. However, it is harder to turn in this case, if
the machine is to be manoeuvred manually.
OPERATING
Make sure that there is the correct quantity of oil in
the engine when driving on slopes (oil level on
“FULL”).
Be careful when driving on slopes. No
sudden starting or stopping when mov-
ing up or down a slope. Never drive
across a slope. Move from the top and
down, and from down to the top.
The machine, equipped with original
accessories must not be driven on slopes
greater than 10º in any direction.
Reduce the speed on slopes and when
moving the machine in sharp turns to
prevent the machine from tipping over
or that you lose control over the ma-
chine.
Do not turn the steering wheel to full
lock when driving in top gear and at full
throttle, as the machine can easily top-
ple over.
Keep hands and feet well away from ar-
ticulated steering joint and seat bracket
to avoid having them squeezed. Never
operate the machine without the engine
casing.
SERVICE AND MAINTENANCE
SERVICE PROGRAM
In order to keep the machine in good condition, as
regards reliability and operational safety as well as
from an environmental perspective, STIGA’s serv-
ice program should be followed.
The contents of this program can be found in the
attached service log.
We recommend that an authorised workshop car-
ries out every service. This guarantees that the
work is performed by trained personnel and with
original spare parts.At every service, the service log should be
stamped. A “fully stamped” service log is a valua-
ble document that improves the machine’s second-
hand value.
PREPARATIONS
Unless otherwise stated, all service and mainte-
nance must be performed on a machine that is
standing still where the engine is not running.
Prevent the machine from rolling, by al-
ways applying the parking brake.
Prevent involuntary engine start by al-
ways stopping the engine, loosening the
spark plug cable from the sparking
plug and earthing it. Remove the minus
(-) cable from the battery.
CLEANING
To reduce the risk of fire, keep the en-
gine silencer/catalytic converter, bat-
tery and fuel tank free from grass,
leaves and oil.
To reduce the risk of fire, regularly
check the machine for oil and/or fuel
leakage.
When washing the machine with water under high
pressure, do not point the jet directly at the trans-
mission.
Do not point jets of water directly at the engine,
use a brush or compressed air in order to clean it.
CHANGING ENGINE OIL
Change the oil for the first time after 8 hours run-
ning (Senator and President after 5 hours), and
then after every 50 hours running or once a year.
Change oil when the engine is warm.
Always use a good grade of oil (service grade SE,
SF or SG).
Change the oil more often (after 25 hours of run-
ning or at least once a season) if the engine has to
operate under demanding conditions or if the am-
bient temperature is high.
The engine oil may be very warm if it is
drained off directly after the engine is
shut off. Therefore, allow the engine to
cool a few minutes before draining the
oil. 
						

							ENGLISHGB
1a. Oil drain hose (rubber):
Loosen the oil drain hose from the fastener. Bend
it out of the engine.
1b. Oil drain pipe (metal):
Unscrew the oil drain plug at the end of the pipe.
Let the oil run out into a collection vessel. Then
take the oil to a recycling station. Do not allow
oil to get on the V-belts.
2a. Bend up the oil drain hose and attach it firmly
to the fastener.
2b. Screw up the oil drain plug. Make sure that the
fibre gasket and the O-ring inside the plug are not
damaged and that they are in the correct place.
3. Remove the dipstick and fill up with new oil.
Oil capacity:
Senator, President – 1.4 l
Royal – 1.9 l (including oil filter)
Pro16, Pro18, Pro20 - 1.7 l (including oil filter)
Oil type summertime (> 4º C): SAE-30
(SAE 10W-30 can also be used. However, oil con-
sumption may increase somewhat if 10W/30 is
used. Therefore, check the oil level more regularly
if you use this type of oil).
Oil type winter (< 4º C): SAE 5W-30
(if this oil is not available, use SAE 10W-30).
Use oil without any additives.
Do not fill too much oil as this can result in over-
heating the engine.
After filling up the oil, start the engine and idle for
30 seconds. Stop the engine. Wait for 30 seconds
and then check the oil level.
Check to see if there is any oil leakage. If neces-
sary, fill up the oil up to the “FULL” mark.
OIL FILTER - ENGINE (Royal - Pro16
- Pro18 - Pro20)
Replace the oil filter after every 100 hours of oper-
ation or once a season.
Before screwing the new filter, oil the filter gasket
with engine oil.
Screw the filter by hand, until the filter gasket
touches the filter attachment. Then tighten ½ to ¾
of a full turn (fig. 17 - 18).
Start the engine and idle to see if any leakage oc-
curs. Switch off the engine, check the oil level. If
necessary, fill up the oil up to the “FULL” mark.
AIRFILTER-ENGINE
Clean the foam pre-filter every 3 months or after
every 25 hours of operation, whichever comes
first.
Clean the paper filter insert once a year or after
every 100 hours of operation, whichever comes
first.
NOTE! The filters should be cleaned more often if
the machine operates on dusty ground.
1. Loosen the wing nut under the fuel tank and
move it backwards (fig. 16). Also loosen the bat-
tery to make it easier to get at the air filter (applies
to Pro16-Pro18-Pro20).
2. Remove the protective cover of the air filter (fig.
19 - 21).
3. Dismantle the paper filter insert and the foam
pre-filter. Make sure that no dirt gets into the car-
burettor. Clean the air filter housing.
4. Wash the pre-filter in liquid detergent and water.
Squeeze dry. Pour a little oil on the filter and
squeeze in the oil.
5. Clean the paper filter insert as follows: Knock it
lightly against a flat surface. If the filter is very
dirty, change it.
6. Assemble in the reverse order.
Petroleum-based solvents such as kerosene must
not be used for cleaning the paper filter insert as
these can destroy the filter.
Do not use compressed air for cleaning the paper
filter insert. The paper filter insert must not be
oiled.
AIRFILTER-CATALYTICCONVERT-
ER (Pro18 - Pro20)
Clean the catalytic converter’s air filter every 3
months or after every 25 hours of operation,
whichever comes first.
1. Remove the cover by pressing in the locking
mechanism with a screwdriver, etc. (fig. 22).
2. Remove the foam filter and wash it in liquid de-
tergent and water. Squeeze dry. Pour a little oil on
the filter and squeeze in the oil.
3. Replace the filter and snap the lock into place.
SPARKING PLUG
Only use a Briggs & Stratton sparking tester to 
						

							ENGLISHGB
check the spark of the sparking plug(s) (fig. 23).
Clean the sparking plug after every 100 hours of
operation or once a season. For replacing a spark-
ing plug, a sparking plug sleeve A and a torsion pin
B are provided in the accessories bag.
The engine manufacturer recommends:
Senator-President: Champion J19LM
Royal-Pro16-Pro18-Pro20: Champion RC12YC
The correct distance between the electrodes is 0.75
mm.
COOLING AIR INTAKE - ENGINE
The engine is air-cooled. A blocked cooling sys-
tem can damage the engine. The engine should be
cleaned at least once a year or every 100 hours of
operation.
Remove the fan casing. Clean the cooling fins on
the cylinder, the fan and the rotating protective
grille (fig. 24 - 25). Clean more frequently if mow-
ing dry grass.
BATTERY
Check the acid level regularly.
The acid level should be between “UPPER “ and
“LOWER” on the battery. When adjusting the lev-
el, only use distilled water (battery water).
The battery acid is extremely corrosive
and can cause burns and injuries to
skin and clothing. Always use rubber
gloves and glasses (goggles) to protect
the eyes. Avoid inhaling any acid va-
pour.
Do not incline the battery too much so
that the battery acid can run out on to
hands and clothing. If this should hap-
pen, flush with lots of water.
If the battery terminals are coated with oxide, they
should be cleaned. Clean the battery terminals with
awirebrushandgreasethem.
LUBRICATION - CHASSIS
The machine’s articulated steering joint has four
grease nipples that should be lubricated with uni-
versal grease after every 25 hours of operation
(fig. 26).
Please note that the fourth grease nipple is not
shown on the picture. It is located on the underside,
on the flexible axle’s front bearing.Senator-President-Royal:
Lubricate the steering cables and steering chain
with universal grease a couple of times per season.
Pro16-Pro18-Pro20:
Apply universal grease to the steering chain a cou-
ple of times each season. If the steering chains are
really dirty, dismantle them, wash them and then
grease them once more.
Apply universal grease to all the plastic bearings a
couple of times per season.
Apply a coating of engine oil to the tension arm
joints a couple of times each season.
Apply a few drops of engine oil to both ends of the
throttle control cable a couple of times a season.
Senator:
The transmission is filled with oil (SAE 80W-90)
upon delivery from the factory. If it is not opened
(which must only be done by a specialist), normal-
ly no topping up of oil should be carried out.
STEERING CABLES (Senator -
President - Royal)
The steering cables should be adjusted for the first
time after the machine has been in operation for 2
- 3 hours, and then after every 25 hours of opera-
tion.
Put the machine in the straight-ahead position.
Tension the steering cables by tightening up the
nuts that are located on the underside of the articu-
lated steering joint (fig. 27). The screws in the ends
of the cables should be held firmly during adjust-
ment so that the cables are not twisted. Use an ad-
justable wrench or similar for this purpose,
inserting it in the key handles in the ends of the
screws. Tension the cables until they are no longer
slack.
Adjust both the nuts the same amount to ensure
that the alignment of the steering wheel is not
changed.
Once the adjustment is complete, turn the steering
wheel as far as it will go in either direction. Check
that the chain does not come into contact with the
pulley, and that the cables do not become entan-
gled with the steering pinions.
Do not tension the steering cables too hard. Other-
wise the steering will be heavy and wear and tear
on the cables will increase. 
						

							ENGLISHGB
STEERING CHAINS (Pro16 - Pro18 -
Pro20)
Adjust the steering chains after every 50 hours of
operation.
Put the machine in the straight-ahead position.
Tension the steering chains by tightening up the
nuts that are located on the underside of the articu-
lated steering joint (fig. 27). Tension until all play
is removed.
Adjust both the nuts the same amount to ensure
that the alignment of the steering wheel is not
changed.
Do not over-tighten the steering chain. This will
cause the steering to become heavy and will in-
crease wear on the steering chain.
PAT E N T –
PROTECTION OF DESIGNS
This machine, or parts thereof, is protected by the
following patent and protection of design:
DESIGN APPLICATION
Sweden no. 99 1095
PATENT APPLICATION
Sweden no. 9900627-2
9901091-0
9901730-3
STIGA reserves the right to modify the product without giv-
ing any prior notice.