WilTec LIFAN 2V90F User manual

Operating instructions
LIFAN Engine 2 V90F
92670
Illustration similar, may vary depending on model
Please read and follow the operating instructions and safety information prior to initial operation.
Technical changes reserved!
Illustrations, functional steps, and technical data may deviate insignificantly due to continuous further
developments.

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The information contained in this document may alter at any time without prior notice. No part of this
document may be copied or otherwise duplicated without prior written consent. All rights reserved.
WilTec Wildanger Technik GmbH cannot be held liable for any possible mistakes in this operating man-
ual, nor in the diagrams and illustrations shown.
Although WilTec Wildanger Technik GmbH has made every possible effort to ensure that this operating
manual is complete, accurate, and up-to-date, errors cannot be ruled out entirely.
If you have found an error or wish to suggest an improvement, we look forward to hearing from you.
Send us an e-mail to:
[email protected]
or use our contact form:
https://www.wiltec.de/contacts/
The most recent version of this manual in several languages can be found in our online shop:
https://www.wiltec.de/docsearch
Our postal address is:
WilTec Wildanger Technik GmbH
Königsbenden 12
52249 Eschweiler – Germany
To return your goods for exchange, repair, or other purposes, please use the following address. Atten-
tion! To allow for a trouble-free complaint or return, it is important to contact our customer service team
before returning your goods.
Retourenabteilung
WilTec Wildanger Technik GmbH
Königsbenden 28
52249 Eschweiler – Germany
E-mail: [e-mail]
Tel: [phone]
Fax: [phone]

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Introduction
Thank you for choosing to purchase this quality product. To minimise the risk of injury, we ask you to
always take some basic safety precautions when using this product. Please read this operating manual
carefully and make sure that you understand it.
Keep these operation instructions in a safe place.
These instructions are an integral part of the petrol engine and should be included if the petrol engine is
passed on to third parties.
Safety instructions
You will find safety instructions in this manual and on the petrol engine itself. Please read and under-
stand their meaning to avoid harm to yourself and others. Below you will find safety instructions, followed
by the content of the respective safety instructions.
•Danger! Non-compliance with any of the following instructions might lead to serious injuries or
even death.
•Warning! Non-compliance with any of the following instructions might lead to serious injuries
or even death.
•Attention! Non-compliance with any of the following instructions might lead to injuries.
•Important! Failure to follow the instructions may result in damage to the petrol engine or other
damage.
Whenever the above information appears in the manual and on the petrol engine, please read it carefully
and observe it when operating. Each instruction informs you of the possible dangers, their conse-
quences, and how to avoid them so that you can minimise the risk of injury.
Different models have different labelling. Please take the actual product as a basis.
Safety precautions
•Familiarise yourself with the operation of all the controls and learn how to switch off the petrol
engine in an emergency. Make sure that the operator of the motor is specially trained.
•Children must not operate petrol engines. Keep the motor out of the reach of children and pets
to avoid accidents.
•The exhaust gas emitted by the petrol engine contains toxic carbon monoxide. Ensure good
ventilation and do not allow petrol engines to be used in a closed room.
•The temperature of the engine housing and exhaust gas emitted is very high when the petrol
engine is running. Therefore, keep a minimum distance of 1 m from buildings or other facilities
and keep the motor away from flammable objects. It is forbidden to cover the petrol engine
during operation.
•This petrol engine is suitable for general use. It is forbidden to use it for other purposes, e.g.,
for a car or motorbike.

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Location of the warning signs
The warning signs draw your attention to possible dangers that could lead to serious injury. Please read
and observe them carefully.
Hot surface! Do not touch!
Position of parts and controls
№
Name
№
Name
1
Spark plug
5
Air cleaner
2
Fuel filter
6
On-button start switch
3
Oil filter
7
Potentiometer button
4
Drain screw
8
Tachometer

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№
Name
№
Name
№
Name
№
Name
1
Oil filler plug
4
Drain screw
1
Main cable
3
Accelerating the
motor
2
Spark plug
5
Dipstick
2
Electronic con-
troller
4
Throttling the mo-
tor
3
Motor starter
6
Silencer
Inspection before commissioning
For your safety and to increase the service life of your device, please take some time to check the
condition of the petrol engine before operation.
Warning!
•Improper maintenance or operation of the petrol engine without fault checking can lead to seri-
ous injury or even death.
•An inspection must be carried out before each operation so that various faults can be rectified.
•Ensure that the motor is on a level surface before inspection.
•Check the following points before each start:
General conditions
•Check for oil and fuel leaks.
•Remove excess dirt and deposits, especially around the silencer.
•Check if there are any signs of damage.
•Check the position of all bonnets and covers and check the fastening of the bolts, nuts, and
screws.
Petrol engine
•Ensure that there is a sufficient fuel level. Prior refuelling can reduce or prevent interruptions
during operation due to the need for refuelling.
•Check the oil level. A low oil level leads to damage to the petrol engine during operation.
•Check the air-filter element. A dirty air filter hinders the air supply to the carburettor and reduces
the power of the motor.
•Before starting the petrol engine, check the equipment and read the operating instructions to
understand the operating instructions and necessary steps.

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Operation
Warning before starting operation
•Before using the petrol engine for the first time, be sure to read the chapter on safety measures
and inspection before use.
•To achieve full performance, it is recommended that the new product is allowed to warm up for
15 min before use.
•Please read the safety instructions carefully and familiarise yourself with starting, switching off,
and operating the motor.
•Do not use the petrol engine if the surface on which it is to be used is inclined at 20° or more.
Warning! Do not use the motor in enclosed spaces. Carbon monoxide in exhaust fumes can reach
dangerous concentrations in enclosed spaces, which can lead to unconsciousness and even death. –
Petrol engines must not be operated in closed rooms, not even in semi-ventilated rooms where people
are present. It is important to ensure that enclosed spaces are adequately ventilated to prevent carbon
monoxide poisoning.
Starting the engine
1. If the fuel tank is equipped with a fuel tap, make sure that the fuel tap is set to “ON” before
starting the petrol engine.
2. Turn the potentiometer button anti-clockwise to the starting position for the idle speed.
№
Name
№
Name
1
On-button start switch
2
Potentiometer button
3. Start the engine by pressing and holding the on-button starter switch until the petrol engine
starts. If the petrol engine does not start successfully after more than 5 s, release the switch for
10 s before pressing it again.
Important! Do not use the starter motor for longer than 5 s, otherwise the starter motor may
overheat or be damaged.
4. Allow the petrol engine to warm up for 2–3 min.
Turning off the engine
To switch off the engine in an emergency, please proceed as follows. Additional information is found in
the user’s manual.
1. Press the on-button start switch.
2. If the fuel tank is equipped with a fuel tap, set the tap to the “OFF” position.

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Maintenance
Proper maintenance of the petrol engine is of great importance for safety, lower fuel consumption, and
smooth operation. It also helps to reduce pollution. You should therefore carry out maintenance on your
petrol engine as carefully as possible. On the following pages, you will find detailed maintenance sched-
ules, regular inspection procedures, and simple maintenance work that can be carried out using ordinary
hand tools. If further professional or complex maintenance work is required, we recommend that you
contact a specialist.
The maintenance schedule covers the regular operation of the petrol engine. If you use the motor in
harsh conditions, e.g., under constant load, at high temperatures, or in a particularly damp or dusty
environment, please contact a specialist to obtain maintenance recommendations for your individual
application.
Please only use original parts for your petrol engine. The use of inferior spare parts can cause damage
to the petrol engine, and this damage cannot be covered by the warranty.
Warning!
Improper maintenance or operation without correcting existing faults can lead to more serious faults or
even serious injury or death. — Please adhere strictly to the inspection and maintenance instructions
and the maintenance schedule in these operating instructions.
Safety precautions
Below, you will find some very important safety instructions. We cannot list all the hazards that can occur
during maintenance. You must decide for yourself if you are qualified to carry out repair work.
Warning! Failure to observe the maintenance instructions and warnings can result in serious injury
or even death. Please be sure to follow the steps and safety instructions in these operating instructions.
Safety instructions
1. The petrol engine must be switched off before any maintenance or repair work is carried out in
order to minimise safety hazards. The following measures should be observed:
•Good ventilation of the workplace is necessary to prevent carbon monoxide poisoning from
exhaust fumes.
•The petrol engine and the exhaust system must cool down before touching them to prevent
burns from hot parts.
•Injuries caused by moving parts should be avoided.
•Do not touch the running petrol engine unless expressly stated otherwise.
2. Read the instructions before commissioning to ensure that you have complete information and
knowledge.
3. Be extremely careful to reduce the risk of fire or explosion when petrol is near the engine. Use
flame-retardant solvents to clean the parts and avoid using petrol. All components coming into
contact with petrol must be kept away from cigarette butts, sparks, and naked flames.
Please note that a specialist is more familiar with your petrol engine and has the necessary equipment
for maintenance and repair. To ensure the best quality, safety, and reliability, only new and original Lifan
parts may be used for repairs or replacements.

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Maintenance schedule
Frequency
Type of intervention
Every
time
During
the 1st
month or
after 40
hours
After 6
months of
100 hours
Every year or
after 300
hours
Every 2 years
or after 500
hours
Motor oil
Check oil level.
X
Replace.
X
X
Air filter
Check.
X
Clean.
X(1)
Replace.
X*
Spark plug
Clean, adjust.
X
Replace.
X
Ignition sen-
sor
Clean.
X
Idling
Check, adjust.
X
Burning
chamber
Clean.
Every 1000 hours of operation
Oil filter
Replace.
Every 200 hours of operation
Petrol filter
Clean.
X
Fuel supply
line
Check.
After 2 years (replace if necessary)
(1) In dusty environments, service more frequently than indicated in the table. — * Only replace paper
element
•It is recommended that an authorised specialist carries out the work unless you are specially
trained and equipped with the appropriate tools.
•For commercial use, it is important to record the operating hours in order to determine the ap-
propriate maintenance cycle.
•Damage resulting from non-compliance with this maintenance schedule is excluded from the
warranty.
Refuelling
Recommended fuel
•It is recommended to use a petrol with 92 octane for this engine.
•Stop the engine and refuel in a well-ventilated area. If the petrol engine has just been running,
allow it to cool down first. It is forbidden to refuel in places where there may be flames or sparks.

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Warning!
•There is a risk of burns and injury when refuelling, as petrol is flammable and explosive.
•Switch off the motor and keep it away from naked flames, sparks, and heat sources.
•Refuel outdoors and wipe up any spilt fuel immediately.
Important!
•Petrol can damage paint and plastic parts. Avoid spilling petrol when refuelling, as damage
caused by petrol splashes is not covered under warranty.
•It is important never to use aged, contaminated, or mixed oil and to ensure that no dust or water
gets into the fuel tank.
•Before checking the oil level, place the petrol engine on a level surface and unscrew the fuel
filler cap. If the oil level is too low, top up the oil. Observe the operating instructions for the
engine and accessories when refuelling.
•Only fill the fuel in a well-ventilated area before starting the petrol engine.
•After operating the petrol engine, wait until it has cooled down completely before operating or
refuelling it again.
•Be careful when refuelling the engine to avoid fuel splashes.
•Under different operating conditions, the oil level may fall below the upper limit value.
•After refuelling, the tank cap should be firmly tightened.
•Avoid storing petrol near lights, stoves, electrical devices, power sources, and other objects that
can produce open flames, sparks, or high temperatures.
•Spilt petrol is not only a potential fire hazard, but also pollutes the environment. Therefore, wipe
up any spilt petrol immediately.
Motor oil
•Engine oil plays a decisive role in the performance of the engine. Please only use 4-stroke petrol
engine oil.
•Check the API label on the engine oil container. Unless otherwise specified, we recommend
engine oil SJ 10 W-30, which should at least correspond to class SE.
•If the average ambient temperature in your area is within the temperature range shown in the
illustration, you can use the appropriate engine oil viscosity from the illustration. For ranges
below −20 ℃, it is recommended to use a 0 W-30 engine oil for easier starting.
Ambient temperature
Check oil level
Make sure that the motor is on a level surface. Make sure that the oil level is within the recommended
range.
1. Start the petrol engine and let it idle for 1–2 min. Leave the motor running for a further 2–3 min
after switching off.
2. Remove and clean the oil dipstick.
3. Insert the dipstick into the oil filler neck and pull it out to check the oil level.
4. If the oil level is too low, open the oil filler cap and fill with the recommended engine oil up to the
upper mark on the oil dipstick.
5. Then refit the oil dipstick and the oil filler plug.

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№
Name
1
Oil filler plug
2
Dipstick
3
Upper limit
4
Lower limit
Important!
•Damage caused by operating a petrol engine with an insufficient oil level is not covered by the
warranty.
•If the oil level falls below the lower safety limit, the engine may come to a standstill or even be
damaged. To avoid accidental burn-out, it is important to check the oil level before every start.
This should be carried out every few months to ensure the long-term protection of the engine.
Oil change
Changing the oil is quick and easy when the petrol engine is warm.
1. Place a suitable container under the petrol engine to collect the used oil. Remove the oil pres-
sure sensor, the drain plug, and the seal.
2. Drain the residual oil completely, then insert the drain plug and a new seal and tighten them.
Important! When disposing of used oil, the environment must not be polluted. We recommend collecting
the used oil in a container and taking it to a recycling centre or recycling workshop. Do not dispose of it
in household waste, do not pour it on the floor, do not dispose of it in the sewage system!
3. Position the petrol engine horizontally and fill with the recommended oil up to the upper mark
on the dipstick.
4. Then reinsert the oil pressure sensor and tighten it.
Replacing the oil filter
1. Drain the oil and then retighten the oil drain plug.
2. Remove the oil filter and empty the oil into the oil reservoir. Please ensure that you do not harm
the environment when disposing of the residual oil and oil filter.
Important! Use a special socket spanner to prevent damage to the oil pressure switch.
3. Clean the filter base and apply a layer of clean engine oil to the new washer.
Important! Make sure that you use an original oil filter. If you use a bad filter, the petrol engine
will be damaged.
4. To install a new oil filter, tighten it by hand until the seal touches the base, then turn it a further
three-quarters of a turn using a special socket spanner (tightening torque of the oil filter: 15 Nm).
5. Fill the crankcase with the recommended amount of oil and then fit the oil filler plug and the oil
dipstick.
6. Start the petrol engine and check for oil leaks.
7. Switch off the petrol engine and check the oil level. If necessary, top up the oil to the upper limit
mark on the dipstick.

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Air filter
A dirty air filter prevents air from entering the carburettor and reduces the performance of the petrol
engine. When using petrol engines in dusty conditions, the air filter should be cleaned more frequently
than specified in the maintenance schedule.
Important! If the air filter element is missing or damaged, dust can get into the petrol engine and accel-
erate its wear. Damage caused for this reason is excluded from the warranty.
Checking
Remove the air filter vent cover and check the element. Clean or replace the air filter. Replace the air
filter element if it is damaged.
№
Name
№
Name
1
Nut of air-filter cover
4
Fastening screw for air filter
2
Air-filter cover
5
Bracket for air filter
3
Air filter element
Cleaning
1. Unscrew the nut on the air-filter cover and remove the air-filter cover.
2. Remove the air-filter element from the air-filter holder.
3. Check the element and replace it if necessary. The air-filter element must be replaced at the
time recommended in the maintenance schedule.
4. Clean the air filter before reusing it.
5. Tap the air-filter insert several times on a solid surface to remove the dust or blow the dust from
the side of the air-filter holder using an air compressor (≤ 2.1 Kgf/cm²).
6. It is forbidden to remove the dust with a brush, as it will be brushed into the fibres of the air filter.
Replace the air filter if there is too much dust.
7. Wipe off the dust outside the air filter or on the cover of the air filter with a damp cloth. Make
sure that the dust does not get into the carburettor through the air duct.
8. Reinsert the air-filter insert and make sure that it and the bracket are firmly seated.
9. Tighten the nut on the air-filter cover.
Spark plug
Recommended spark-plug model: F6RTI-5. Commercially available petrol engines can be operated in
the correct temperature range with the recommended spark plug.
Important!
•The use of an unsuitable spark plug will damage the petrol engine.

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•If the petrol engine has just been running, wait until it has cooled down before servicing the
spark plug.
•To ensure normal operation of the petrol engine, the spark-plug gap must be set correctly and
there must be no deposits.
1. Remove the spark-plug cap and remove the dirt from around the spark plug.
2. Remove the spark plug using a special 21-mm socket spanner.
3. Check the spark plug and replace it if it is damaged or heavily clogged, the seal is aged, or
the electrodes are excessively worn.
4. Measure the electrode gap with a feeler gauge. If necessary, bend the side electrode to
adjust the distance.
5. The spark-plug gap is 0.7–0.8mm.
6. Install the spark plug carefully to avoid thread misalignment.
7. After installing the spark plug, tighten the spark plug with the seal using a 21-mm spark-plug
socket spanner.
Important!
•When installing a new spark plug, tighten the seal by half a turn more.
•When installing a used spark plug, tighten the seal by an eighth to a quarter of a turn more.
№
Name
1
Spark-plug connector
2
Spark plug
3
Side electrode
Troubleshooting
Low motor power
Problem
Possible cause
Proposed solution
Engine power is insuffi-
cient, engine speed
drops, or engine even
stops
Ignition system
Incorrect ignition timing
Replace ignition coil.
Fuel supply system
Air mixture in the oil circuit
Release air.
Incorrect setting of main
nozzle
Set new.
Needle valve or main noz-
zle clogged
Clean and blow out.
Fuel tap blocked
Clean or replace.
Too many carbon depos-
its in combustion chamber
Clean out.

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Suction system
Air filter clogged
Clean or replace element.
Air leakage in the suction
system
Repair or replace.
Poor compression
Piston, cylinder, or piston
ring worn
Replace.
Air outlet between cylin-
der block and cylinder
head.
Replace cylinder gasket
Incorrect valve clearance
Readjust.
Poor valve tightness
Grind or replace.
Problems starting the engine
Problem
Possible cause
Proposed solution
Normal cyl-
inder pres-
sure
Normal
sparking
of the
spark
plug
Fault in
the fuel-
supply
system
Fuel sup-
ply is not
smooth
Not enough fuel in the fuel tank
or fuel tap closed
Fill with fuel, open the
fuel tap.
Ventilation of fuel-filler cap
blocked
Clean the vent open-
ing.
Fuel tap blocked
Clean.
Main nozzle not set correctly or
clogged
Readjust, clean, blow
out.
Needle valve or float jammed
Repair/replace.
The fuel
supply is
smooth
Fuel too dirty or spoilt
Replace fuel, clean
carburettor.
Water in fuel
Replace fuel, clean
carburettor.
Too much fuel in the cylinder
Drain excess fuel, dry
spark plug.
Wrong fuel brand
Select the correct fuel
brand according to the
requirements.
Normal
fuel sup-
ply sys-
tem
Normal
sparking
Spark
plug is
damaged
Too many carbon deposits and
dirt around the electrodes
Clean.
Insulators damaged
Replace spark plug
Electrodes badly burnt
Replace spark plug.
Wrong spark plug gap
Adjust.
Spark
plug
works
smoothly
No spark-
ing
High-pressure coil damaged
Replace.
Ignition coil damaged
Replace.
Magnet loses magnetic force
Magnetise/replace.
Abnormal
cylinder
pressure
Normal
fuel sup-
ply sys-
tem
Normal ig-
nition sys-
tem
Spark
plug
works
smoothly
Piston ring excessively worn or
broken
Replace.
Piston ring jammed
Remove carbon de-
posits.
Spark plug not tightened or in-
stalled without gasket
Tighten with a gasket.

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Air outlet between cylinder
block and cylinder head.
Replace cylinder gas-
ket.
Air outlet in the valves
Grind or replace.
Sudden failure
Problem
Possible cause
Proposed solution
Sudden failure
during operation
Fuel supply sys-
tem
Fuel consumed
Fill in fresh fuel.
Carburettor clogged
Check the fuel supply and
pump and clear any blockages.
Float leaking
Repair.
Needle valve jammed
Repair.
Ignition system
Short circuit due to a breakdown
or carbon deposit on the spark
plug
Replace spark plug.
Side electrode of the spark plug
has fallen off
Replace spark plug.
Spark-plug cable dropped
Repair or replace.
Breakdown of the ignition coil
Replace.
Oil-pressure
system
Too little oil in the tank
Check and top up oil.
Other
Cylinder severely damaged or
valves broken
Repair or replace damaged
parts.
Abnormal noises
Problem
Possible cause
Proposed solution
Knocking noises
Piston or piston ring worn
Replace worn parts.
Connecting rod, piston pin, and piston-pin
bore worn
Replace worn parts.
Worn crankshaft
Repair or replace.
Piston ring broken
Replace piston ring.
Deflagration with
metallic sound
Too much carbon build-up in combustion
chamber
Remove carbon deposits.
Spark-plug-electrode gap too small
Set the electrode clearance correctly.
Engine flooded with fuel
Check carburettor.
Unsuitable fuel type
Replace fuel.
Engine overheating
See table below.
Engine overheating
Problem
Possible cause
Proposed solution
Engine overheat-
ing
Incorrect ignition timing
Replace ignition coil.
Insufficient oil supply
Add oil.
Exhaust clogged
Clear obstruction.

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Air leakage in the bonnet
Repair damaged part.
Air ducts blocked
Clean slats.
Cooling fan damaged
Replace and reinstall.
Piston ring worn, air flow between cylinder
and crankcase
Replace worn parts.
Hints and recommendations
Storage
1. Preparing for storage: Proper preparation for storage is important to prevent damage to the
petrol engine and to maintain its appearance. Observe the following points to prevent corrosion
and rust, keep the performance and appearance of the engine in good condition, and ensure a
smooth restart.
2. Cleaning: Allow the petrol engine to cool down for at least 30 min after switching it off before
cleaning it. Remove dirt from the entire exterior surface, repair damage to the paint, and apply
a thin layer of oil to prevent rusting.
Important! If you clean the petrol engine with a hose or a high-pressure cleaner, there is a possibility
that water can penetrate through the openings of the air filter or the silencer. The water may get into the
air-filter element and from there into the air filter or silencer, which can damage the cylinder.
Fuel
•Petrol can oxidise and spoil during storage. Prolonged storage of petrol leads to starting diffi-
culties and gelatine-like deposits. If the petrol in the engine deteriorates during storage, it is
necessary to repair or replace the carburettor or another part of the fuel system.
•The service life of the petrol in the tank or carburettor depends on various factors, e.g., the
mixing ratio, the storage temperature, and the filling level. The air in an unfilled tank can also
cause the petrol to deteriorate more quickly, as can high temperatures. It is possible for petrol
to spoil within 30 days or less, especially if the oil has become old.
Important! Any damage to the fuel system or loss of performance of the petrol engine due to improper
storage by the user is not covered by the warranty.
Draining fuel from the fuel tank and carburettor
Warning!
•Petrol is highly flammable and explosive and can cause severe burns if handled incorrectly.
•Keep the petrol away from heat sources, sparks, or naked flames.
•In the event of spillage, remove the petrol immediately.
1. Remove the fuel line attached to the side of the petrol engine and drain the fuel from the fuel
tank into a container provided for this purpose. If the fuel tank is equipped with a fuel tap, turn
the fuel tap to “ON” to drain the fuel. After you have completely drained the fuel, reconnect the
fuel line.
2. Loosen the carburettor drain plug to drain the remaining oil into a container and then retighten
the drain plug.
Motor oil
1. Replace the engine oil.
2. Remove spark plug.
3. Fill about 5–10 ml of new engine oil into each cylinder.

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4. Set the petrol engine switch to “ON” and hold it down for a few seconds so that the oil is dis-
tributed in the cylinder.
5. Refit the spark plug.
№
Name
1
Drain screw
2
Overflow pipe
Storage warning
•If you store your petrol engine and there is still petrol in the fuel tank or carburettor, you must
ensure that the petrol vapours do not ignite and cause a serious accident. Choose a well-venti-
lated storage location and keep away from all appliances that can produce an open flame, e.g.,
heaters, water heaters, tumble dryers. Also avoid starters or other power consumers that can
generate sparks.
•Avoid places with high humidity as far as possible, as appliances located there are very sus-
ceptible to rust and corrosion.
•Store the petrol engine horizontally. Avoid tilting it to prevent fuel or oil leaks.
•If the fuel remains in the tank, set the fuel tap to “OFF” to prevent leakage.
•Cover the cooled petrol engine and the exhaust system to prevent dust deposits.
•Some flammable materials can be ignited or melt by the hot petrol engine and exhaust system.
It is important not to cover the engine with plastic film, as the impermeable films allow ambient
moisture to condense, which can accelerate rust and corrosion. If the engine is equipped with
a battery, it is recommended that the battery is removed and stored in a cool, dry place and
charged monthly to extend its service life.
Retrieving from storage
•Check the petrol engine according to the instructions in the section “Inspection before commis-
sioning.”
•If the fuel has been drained before storage, fill the fuel tank with new petrol and check the tank
to ensure that the petrol is clean. Over time, petrol can oxidise or go bad, making it difficult to
start the engine.
•It is normal for a petrol engine to emit smoke when starting if preservative oil has been applied
to the outside of the cylinder.
Transport
•If the petrol engine has just been running, it should cool down for at least 15 min before it is
loaded onto the transport vehicle. A hot petrol engine and a hot exhaust system can endanger
people and flammable materials in the vicinity.
•The petrol engine should be kept level to prevent oil from leaking during transport. If the fuel
tank has a fuel tap, this should be turned to “OFF.”

© by WilTec Wildanger Technik GmbH Item 92670 Page 17
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Connection between starter motor and battery
Recommended battery: 12 V/45 Ah
Make sure that the battery cables are not connected in reverse order, otherwise a short circuit may
occur. First connect the positive cable to the battery and then the negative cables so that accidental
contact between positive and earth does not cause a short circuit.
Warning!
•Incorrect handling can cause the battery to explode and cause serious injury to people in the
vicinity.
•Keep the battery away from sparks, flames, and other flammable materials.
Important! The battery terminals, clamps, and corresponding accessories contain lead and lead com-
pounds. Wash your hands after touching them.
1. Connect the positive cable of the battery to the start relay.
2. Connect the negative cable of the battery to the fastening screw of the petrol engine, the ground
screw, or another well-grounded connection point.
3. Connect the positive cable of the battery to the positive terminal of the battery as shown.
4. Connect the negative cable of the battery to the negative terminal of the battery.
5. Apply grease to the poles and cable ends.
№
Name
1
Negative pole (−)
2
Starting relay
3
Positive pole (+)
Carburettor change for high altitudes
•At higher altitudes, the standard mixture ratio for the carburettor is too rich, which leads to a
reduction in performance and increased fuel consumption. A mixture that is too rich also leads
to contamination of the spark plug, which can cause starting difficulties. When operating a petrol
engine at different altitudes, exhaust emissions increase with the operating time.
•The performance of a petrol engine can be improved at high altitudes by adjusting the carburet-
tor. If the engine is operated permanently at high altitudes (≥ 1500 m), please contact a specialist
to adjust the carburettor. However, the output decreases by 3.5 % every 300 m above sea level.
If the carburettor is not adjusted, the performance drops even more.
Important! The carburettor must be correctly adjusted so that it is adapted to the conditions at high
altitudes. A petrol engine with an incorrectly adjusted carburettor cannot be used in areas with low alti-
tudes (< 1500 m) as the fuel mixture is too weak. This can cause the motor to overheat and cause
serious damage. Please contact a specialist to have the carburettor setting adjusted before using the
petrol engine at low altitudes.

© by WilTec Wildanger Technik GmbH Item 92670 Page 18
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Technical specifications
Model name
2V90F
Bore x stroke (㎜)
90 × 78.5
Cubic capacity (㎤)
999
Fuel
Unleaded petrol
Max. Net torque (Nm / rpm)
69.50 / 2800
Max. motor power (kW / rpm)
24 / 3600
Motor speed (rpm)
3600
Motor power (hp / kW)
33.31 / 24.50
Motor type
4-cycle 2-cylinder V-motor with air cooling
Engine oil capacity (ℓ)
2.4
Net power (kW / rpm)
24.5 / 3600
Product type
Motor
Starter
E-start
Compression ratio
8.9:1
Ignition system
Transistor/magneto ignition (TCI)
Fuel
Petrol ≥ 92 octane
Lubricant
SJ 10 W-30
Amount of lubricant (ℓ)
2.3
Spark plug
F6RTI-5
Spark-plug gap (㎜)
0.7–0.8
Cooling system
Ventilation
Direction of rotation of the PTO axis
Anti-clockwise (viewed from the dispensing side)
Note! The technical data may vary for different types and may change at any time without prior notice.
Circuit diagram
Motor with electric starter and oil protection system
Important note: Reproduction and any commercial use (of parts) of this operating manual, requires a
written permission of WilTec Wildanger Technik GmbH.