or call 844-DUROMAX Monday - Friday 7am to 5:00pm. PST
Product Support (Product: information, application, service info & warranty questions)
support@duromaxpower.com
or call 844-DUROMAX Monday - Friday 7am to 5:00pm. PST
This manual provides information regarding the operation and maintenance of these products.
We have made every effort to ensure the accuracy of the information in this manual.
We reserve the right to change this product at any time without prior notice.
Please keep this manual available to all users during the entire life of the engine.
PARTS DESCRIPTIONS .............................................................................................................................................
FUEL AND FUEL TANK........................................................................................................................................6
STARTING THE ENGINE ............................................................................................................................................7
RUNNING THE ENGINE..............................................................................................................................................8
EXHAUST CONTROL SYSTEM.................................................................................................................................9
EXPLODED VIEW AND PARTS LIST(7HP)............................................................................................................24
EXPLODED VIEW AND PARTS LIST(16HP)..........................................................................................................27
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SAFETY PRECAUTIONS
WARNING:
Before operating the engine, be sure to read and familiar with the manual carefully, otherwise
personal injury or equipment damage may produce.
Please pay special attention to the following:
1. Running the engine in a well-ventilated place, keep it at least one meter away from building
walls or other equipments, keep away from inflammables such as gasoline, matches and so on
to avoid possibility of fire.
2. Keep the engine out of reach of children and pets to avoid accidents.
3. Operator of engine has been specially trained.
4. Refuel in a well-ventilated area with the engine stopped, and in places refueling or storing
gasoline, no smoking and any flames or sparks.
5. Refuel the fuel tank not too full so as to avoid fuel’s spilling out. If there is spilled fuel around, be
sure to clean it thoroughly before starting.
6. Locate the engine on a level-working platform to avoid fuel’s spilling out.
7. Maker sure the fuel filler cap is tightened securely.
8. The exhaust muffler is very hot during running the engine even after the engine stops. Never
touch it, or you may get burns. Transport or store the engine with it cooling down entirely.
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PARTS DESCRIPTION
The main parts of engine are located as follows
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BATTERY CONNECTION (electric-start type)
In the case that the specifications of the battery are 12V and more than 18A.h connect its
positive lead to the electromagnetic coil while connect its negative lead to engine mount strew,
base screw or any place capable of grounding with the engine well.
Make sure the battery leads are connected tightly and no corrosion is found. If any, eliminate it.
WARNING:
● The battery may give off explosive gas;
keep sparks, flames and cigarettes away.
Charge or use it in an area with good
ventilation.
● The battery contains sylphlike acid
(electrolyte). Contact with skin or eyes
may cause severe burns. Wear protective
clothing and a face shield.
If electrolyte gets in your skin, flush with
water; if gets in your eyes, flush with water for at least 15 minutes and call a physician at once.
● Electrolyte is poisonous. If swallowed, drink large quantities of water or milk, and follow with
milk of magnesia or vegetable oil and oil a physician.
● Keep out of reach of children.
CAUTION:
● Do not add tap water to the battery instead of distilled water, or the battery life will be
short-need.
● Do not add distilled water over electrolyte upper level mark, or electrolyte will spill out to corrupt
the engine parts. If so, be sure to wash them away with water.
● Make sure not to connect the battery leads in reverse or-deer, or short-circuit or breaker’s
cutting may result.
PRE-OPERATE INSPECTION
ENGINE OIL
CAUTION:
● Engine oil is key factor in deciding the engine’s
performance. Do not apply engine oil with additives
or 2-stroke gasoline oil, as they haven’t enough
lubrication, which may shorten the en-gene’s service
life.
●Check the engine with it
stopped on a level ground.
Engine oil recommended:
SAE10W-30
As viscosity varies with
regions and temperatures,
so the lubricant has to be
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selected in accordance with our recommendation.
Check
1. Ensure that the engine is stopped on a level ground.
2. Remove the dipstick and clean it.
3. Reinsert the dipstick into the oil filler without screwing it, and check oil level.
4. If the oil level is too low, add the recommended engine oil up to the oil filler neck.
5. Reinstall the dipstick.
CAUTION: Run with insufficient engine oil may damage the engine severely.
OIL IN THE REDUCTION GEAR BOX (only for the model
equipped with it) 1/2 Reduction gear with an auto-centrifugal
clutch
Brand of the box oil is the same as that of engine oil.
Oil capacity: 0.5liters for 190N, 0.3liters for 170N. Check the oil
lever in the following order.
1. Remove the dipstick and clean it.
2. Reinsert the dipstick without screwing it in, and then check
oil level
.
3. If the oil level is too low, add the
recommended engine oil until it arrives the
upper level mark.
4. Reinstall the dipstick.
AIR CLEANER
I. Double-core type
Dismantle the air cleaner housing and check its
filter element, make sure it clean and intact,
otherwise clean or replace it.
II. Dust-collecting type
1. Dismantle the dust-collecting hood and check
the filter element of the air cleaner; make
sure it is clean and intact, otherwise clean or
replace.
2. Check whether there is any dust or dirt inside
the dust-collecting hood, if any, clears away.
III. Single-core type
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Dismantle the air cleaner housing and check its filter element, make sure it is clean and intact,
otherwise clean or replace.
IV. Oil-bath type
1. Dismantle the air cleaner housing and check its core, make sure it is clean and intact,
otherwise clean or replace.
2. Check oil level and oil quality. If the oil level is too low, add the recommended engine oil up to
oil level mark.
CAUTION:
Never run the engine without an air cleaner, or severe wear of the engine may result.
FUEL AND FUEL TANK
Fuel
To ensure that the engine runs smoothly use only FRESH, UNLEADED GAS WITH AN
OCTANE RATING OF 87 OR HIGHER. Using unleaded gasoline will decrease the possibility of
producing car boll deposit and will prolong the engine’s service life. Never apply used or polluted
gasoline or a mixture of gasoline with engine oil. Make sure the fuel is free of dirt and water.
Gasoline Containing Alcohol
If you decide to use a gasoline containing alcohol (fuel blend), be sure its octane rating is at least
as high as that recommended by the company. There are two types of“gasohol”. One contains
ethanol, and the other contains methanol. Neither gasoline containing more than 10% ethanol nor
5% methanol is allowed to be used. If methanol content in the fuel blend exceeds 5%, it may bring
bad effect on the engine performance, besides, it may damage metals, rubber and plastic parts.
CAUTION: Handle fuel with care because it change plastic and painted surface.
It is normal when you hear occasionally light spark knock or pinking with the engine running under
heavy load.
If “spark knock” or “pinking” occurs at a steady speed under normal load, change brand of
gasoline; if Such phenomena still happen, consult your dealer for help, otherwise the
engine may be damaged.
Fuel Tank
Fuel tank capacity: 3.6liters for 170N , 6.5liters for 190N.
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Check
1. Remove the fuel filler cap and check fuel level.
2. If the fuel level is too low, refuel the tank. Remember adding
fuel not over the fuel filler shoulder.
WARNING:
● Gasoline is extremely flammable and is explosive
under certain conditions. Refueling in a well-ventilation
area with the engine stopped. Do not smoke and smoke
and allow flames or sparks in the area where gasoline
is stored or where the fuel tank is refueled.
● Do not overfill the tank (there should be no fuel in the
filler neck). After refueling, make sure the fuel filler cap
is set back securely.
● Be careful not to spill fuel when refueling. Spilled fuel
or fuel vapor may ignite. If any fuel is spilled, make
sure the area is dry before starting the engine.
● Avoid repeated or prolonged contact with skin or
breathing of fuel vapor. Keep out of reach of children.
STARTING THE ENGINE
1. Push the fuel cock to“ON”.
2. Push the choke lever to “CLOSE”.
NOTE: if the engine is hot, closing the choke is unnecessary.
3. Move left the throttle lever a little.
4. Start the engine as follows:
a) Hand-operated kick-starter Push the engine switch to“ON”. Pull slightly the starting rope handle
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up until feeling anti-action, and then make a rapid pull.
CAUTION:
Releasing the handle suddenly may make it hitting the
engine. Release the handle slowly conforming to its
recoiling force.
b) Electric starter
Push the engine switch to “START”and remain there
until the engine starts. Once the engine starts, reset the
engine switch to “ON”.
CAUTION:
Use the engine switch not more than 5 minutes each time to avoid
damage of the engine. Try once more 10 minutes later after last
attempt failures.
RUNNING THE ENGINE
1. Preheat the engine and push back the choke lever to “OPEN”.
2. Set the throttle lever in proper position to ensure the engine runs
at required velocity.
ENGINE OIL ALARM
The engine oil alarm is designed to function when the engine oil in the crankcase is insufficient.
Lack of engine oil may damage the engine. Oil may damage the engine. Once oil level in the
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crankcase is too low, the engine oil alarm will stall the engine automatically to make it free of
damage while the engine switch is still at “ON”.
CAUTION:
If cannot restart the engine, check the engine oil level first before go to other check items.
BREAKER (Electric-start type)
The breaker will cut off automatically to protect the charging circuit of the battery in the case that
short circuit or incorrect connection of the battery poles occurs.
The green indicator in the breaker will jump out with the circuit cutting off. After finding troubles and
troubleshooting, depress the breaker button to tune the breaker on.
OPERATING ON HIGHLANDS
On highlands, the standard mixture ratio is relatively too big so the engine performance may be
impaired while the fuel consumption may increase, besides, too big mixture ratio will pollute the
spark plug to result in starting the engine difficultly. This problem can be solved by amending the
carburetor technological status. If always using on highlands with a height above sea level of 1800
meters, ask your dealer for doing the job.
CAUTION:
Amended engine applicable to highlands may be damaged seriously in area below altitude of 1800
meters for overheating, because its mixture ratio is too small for operation in low altitude area. In
the case, ask your dealer to recover the engine to its normal technical status.
STOP
In emergency, push the engine switch to “OFF” to stall the
engine; to stop it in normal, do as follows:
1. Push right the throttle lever to the bottom.
2. Push the engine switch to “OFF”.
3. Set the fuel cock to “OFF”.
CAUTION:
Sudden stopping at high speed under heavy load is
forbidden, otherwise damage will result.
EXHAUST CONTROL SYSTEM
With the engine running, carbon monoxide, oxide of nitrogen and hydrocarbon will produce, and in
certain conditions, oxide of nitrogen and hydrocarbon will react chemically each other to make
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smoke while carbon monoxide is toxic, so exhaust control of them is very important. The company
decreases the exhaust emissions by introducing poor-fuel carburetors and other devices into the
engine to solve the problem.
To keep the exhaust of your engine with in the standard exhaust emission, pay attention to the
following:
1. Maintenance
Maintain the engine
periodically in accordance
with the maintenance
schedule in the manual. The
maintenance schedule is
made out on the base of
normal use in normal
conditions, if using under
heavy load, dusty or wet
circumstances or in high
temperature, service of the
engine should be done more
often.
2. Replacement of Parts
We recommend that you
should choose such parts which are manufactured by the company or equivalent to these in quality
as replacement ones. Replacement without so high quality as the original may impair the exhaust
the exhaust control system in effectiveness.
3. Modifying
Modifying the exhaust control system may make actual exhaust emissions exceeding statutory
limit values. Illegal modification as such:
a) Dismantle or modify any part of air intake or exhaust system.
b) Modify or take off speed-adjusting connection device or speed adjustment device to result in the
engine’s running beyond the set parameters.
4. Problems Affecting Exhaust Emissions
a) Difficult starting or difficult stopping.
b) Unstable idling.
c) Give off black smoke or consume too much fuel.
d) Poor ignition sparks or sparks returned.
Once you find any of above problems, contact your dealer for help.
MAINTENANCE
MAINTENANCE SCHEDULE
Each
Frequency
Item
Oil level check √ Engine oil
Replace √√
Oil level check √ Reduction gear
oil
PDF created with pdfFactory Pro trial version www.pdffactory.com
Fuel supply line Check Every two years (do a replacement if necessary)
CAUTION:
Use only parts from the company or equivalents in quality; otherwise engine damage may result.
NOTE:
*: only for inside-ventilating double-core carburetors.
**: only for paper core air cleaners. Every two years or 600 hours’ later for dust collecting air
cleaners.
① More often than that in the schedule if in dusty circumstances.
② Should be done by your dealer unless you are specially trained and is well equipped with tools.
WARNING:
Stall the engine before service. If service is required with the engine running, be sure to keep good
ventilation in the area. The exhaust emissions from the engine contain toxic carbon monoxide,
inbreathing of it may result injury and even death.
REPLACEMENT OF ENGINE OIL
A still hot engine is helpful to drain out the engine oil in the crankcase rapidly and entirely.
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1. Turn off the oil filler cap and drain plug to drain engine oil
thoroughly. Reinstall the drain plug and screw in securely.
2. Fill the specified engine oil up to the upper level mark.
3. Reinstall the oil filler cap.
Engine oil capacity in the reduction gear box is 0.3 0.5 liters,
engine oil capacity in the crankcase is 0.6(1.1) liters.
NOTE:
Do not dump oil containers or discarded engine oil into rubbish
boxes or onto the ground. For the sake of environmental
protection, we suggest you take in discarded engine oil with a
closed container and bring to local recycling station.
SERVICE OF AIR CLEANER
A dirty air cleaner may block enough air’s flowing into the
carburetor. To keep the carburetor in good working conditions,
please service the air cleaner periodically. If operating the engine
in extremely dusty area, the job should be done more often.
WARNING:
Never clean the air cleaner core in gasoline or low flash-point
detergents, or explosion may happen.
CAUTION:
Never run the engine without an air cleaner, or air with dirt and dust may enter the engine so speed
the engine’s wear.
Dual element type
Unscrew the wing nut, dismantle the air cleaner housing.
Check if the two cores are damaged, if so, replace with new
one.
a) Foam filter element: clean with home detergents and
warm water (or non-flammable or high flash-point cleansing
solvents) and dry up, then soak in clean engine oil until
saturated. Squeeze out excess oil, otherwise, the engine
will discharge smoke in starting stage.
b) Paper filter element: knock the core against a solid plane
to get rid of accumulated dust or blow out dust from inside to
outside with high-pressure air flow (not more than 30psi).
Never clean with a brush, as brushing may force the dust
into the core fiber. If the core is extremely filthy, replace with
a new one.
Dust-collecting type
1. Unscrew the wing nut, dismantle the air cleaner housing,
check if the two cores are damaged, if so, replace with new
one.
a) Foam filter element: clean with home detergents and
warm water (or non-flammable or high flash-point cleansing solvents) and dry up, then soak in
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clean engine oil until saturated. Squeeze out excess oil, otherwise, the engine will discharge
smoke in starting stage.
b) Paper filter element: knock the core against a solid plane to got rid of accumulated dust or blow
out dust from inside to outside with high-pressure air flow (not more than 30psi). Never clean with a
brush, as brushing may force the dust into the core fiber. If the core is extremely filthy, replace with
a new one.
2. Clean the dust-collecting hood: screw off the three special semi-round screws and remove the
hood, wash parts with water and then dry up. Reinstall the hood.
CAUTION:
● When reinstalling the dust collecting core air cleaner, make sure to embed the fin on the pre-air
cleaner hood in the dent in the dust-collecting hood.
● Install the air guide in correct order.
Single-core type
1. Remove the wing nut and air cleaner housing, and take out the filter element.
2. Clean with home detergents (or high flash-point cleansing solvents) and warm water, and dry
up.
3. Soak in clean engine oil until saturated; squeeze excess oil, or the engine will exhaust smoke in
starting stage.
4. Reinstall the filter element and air cleaner housing.
Oil bath type
1. Remove the nut and air cleaner housing, and take out the filter element.
2. Clean with home detergents (or high flash-point cleansing solvents) and warm water, and dry
up.
3. Soak in clean engine oil until saturated. Squeeze excess oil, or the engine will discharge smoke
in starting stage.
4. Empty the air cleaner housing of oil. Clear away the dust inside with non-flammable or high
flash-point cleansing solvents, and dry it up.
5. Fill the air cleaner housing with the specified engine oil up to the standard oil level mark.
6. Reinstall the air cleaner.
WASHING OF DEPOSIT CUP
Set the fuel cock at “OFF”, disconnect the
deposit cup and O-ring. Wash in non-flammable
or high flash-point cleansing solvents, and then
try them up, at last, reinstall it. Set the fuel cock
to “ON” and check for leaks.
WARNING:
Gasoline is extremely flammable and explosive
in certain condition. Keep cigarette, sparks and
open flames away.
● After reinstalling the deposit cup, make sure the area around the engine is dry enough.
SPARK PLUG
Spark plug type: BPR6ES (NGK) or NHSP LD F6RTC
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Proper spark plug clearance ensures the engine’s normal running under no deposit around the
spark plug. Warning Be careful not to touch the muffler during or just after running the
engine.
1. Remove the spark plug cap.
2. Clear away dirt around the spark plug base.
3. Dismantle the spark plug with a spark plug
wrench.
4. Clean with a steel brush. If the insulator is
damaged, replace the spark plug instead.
5. Measure the spark plug clearance with a
feeler. The clearance should be 0.7~0.8mm.
If adjustment is necessary, bend the side
electrode carefully.
6. Check if the spark plug gasket is in good
conditions, or replace with a new one. Screw
on the spark plug to the bottom first by hand
and then screw in by a spark plug wrench. If
a new spark plug is used, twist 1/2 more
turns after impacting the gasket, if reinstall
the original one, just twist 1/8-1/4 more
turns.
CAUTION:
● The spark plug must be tightened securely, or it may become very hot to damage the
engine.
● Only use recommended spark plug or the equivalent. Incorrect heat range of the spark
plug may damage the engine.
CARBURETORIDLING
ADJUSTMENT
1. Start and preheat the engine until arriving
at the normal working temperature.
2. Obtain standard idling by adjusting the
throttle fixing screw under the engine’s
idling. Standard idling: 1700±150rpm.
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TRANSPORT, STORAGE AND REMOVAL FROM STORAGE
TRANSPORT
Transport with the fuel cock turned off. Transport or store the engine when it is cool so as to avoid
getting burns or fire.
CAUTION:
Do not incline the engine so as to avoid fuel’s spill. Spilled fuel or fuel vapor may ignite to cause
fire.
STORAGE
If the engine is not kept in use for a long time, be sure to store it properly. Make sure the storage
area is dry and free of dust.
1. Drain the fuel ...
a. With the fuel valve in the OFF position, remove and empty the sedi-ment cup.
b. Turn the fuel valve to the ON position and drain the gasoline from the fuel tank into a suitable
container.
c. Replace the sediment cup and tighten securely.
d. Drain the carburetor by loosening the drain screw. Drain the gasoline into a suitable container.
WARNING: Gasoline is extremely flammable and is explosive under certain conditions. Do not
smoke or allow flames or sparks in the area.
2. Replace engine oil.
3. Disconnect the spark plug. Fill about a spoon of fresh engine oil from the spark plug mount hole
into the cylinder. Crank the engine up to distribute engine oil evenly. Reinstall the spark plug.
4. Pull the starting rope slowly until feeling a slight anti-action, and then keep pulling it so as to
align the arrow of the starting sleeve with the hole of the starter. At this time, both the inlet and
outlet valves are closed so help prevent the engine inside from rusting.
5. Electric starter: disconnect the battery and store in dry and cool area. Charge once every
month.
6. Cover the engine so keep dust away.
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REMOVAL FROM STORAGE
Before reusing, service the engine in accordance with the instruction of the table
STORAGE TIME SERVICE ITEM
Within one month Non
One ~ tow months
Two month ~ one
year
Above one year
⑴ Screw off the drain plug and drain out fuel in the carburetor.
⑵ Turn off the engine switch first, disconnect the deposit cup and empty it.
Note: for the sake of environmental protection, we recommend to fill the discarded fuel into a
closed container and bring to local recycling station. Never pour freely.
Drain out original fuel of the fuel tank and
refuel
Drain out original fuel of the fuel tank and
refuel;
Drain out fuel in the carburetor①;
Empty the deposit cup②
Drain out original fuel of the fuel tank and
refuel;
Empty the fuel cup in the carburetor①:
Empty the deposit cup②
WARNING:
Fuel is extremely flammable and explosive under certain conditions. Keep cigarette, open flames
and sparks away from operating site.
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SPECIFCAIONS
MAIN SPECIFICATIONS
Model
XP7HP XP7HPE XP16HP XP16HPE
Items
Engine type 4-strok, OHV,25°,single-cylinder, force air-cooled
bore×stroke(㎜)
Rated
power(kW/rpm)
Max.
torque(N·m/rpm)
Displacement(ml) 208 420 420
Starting type
Ignition type Induction ignition
Lubricating type splashing
There is no enough fuel
in fuel tank of fuel cock is
closed.
Air vent in the fuel filler
cap is clogged.
Fuel cock is clogged. Clean first and then dredge.
Improper or clogged main
oil flow hole.
Torque Value(N﹒m)
Fill fuel, open fuel cock.
Dredge air vent.
Readjust or clean, blow to get through.
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supply.
1. Normal cylinder
compression.
2. Normal spark plug
spark.
3. Something wrong
with the fuel
system.
4. Smooth fuel flow.
1. Normal cylinder
compression.
2. Normal fuel
supply.
3. Normal
high-pressure coil
spark.
4. Spark plug is in
bad conditions.
1. Normal cylinder
compression.
2. Normal fuel
supply.
3. No high-pressure
coil spark.
4. Normal spark
plug.
1. Poor cylinder
compression.
2. Normal fuel
supply system.
3. Normal ignition
system.
Needle valve is not
closed properly or start
Dismantle needle valve and repair, clean,
blow to get through.
hole is clogged.
Float is damaged or
Repair float
sticking.
Fuel is too filthy or
Replace
deteriorated
There is water in fuel Replace
Too much fuel in engine Drain extra fuel, dry up spark plug
Clear away
and dirt around
electrodes.
Electrodes are burn
Replace spark plug
damaged seriously or
insulators damaged
Improper electrodes gap Adjust to proper value
High-pressure coil is
Replace
damaged
Ignition coil is damaged Replace
Magneto loses
Replace
magnetism
Piston ring is worn to or
Replace
even over its wear limit
Piston ring is broken Replace
Piston ring is sticking Clear up carbon fouling
Spark plug is not installed
Tighter with a gasket in
tighten or without a
gasket
Air leakage between
cylinder block and
cylinder head
Check cylinder gasket, and the flatness of
the surface by which cylinder block
contacting with cylinder head, tighten
cylinder head bolts in stipulated order to
stipulated torque.
Air leakage in valves
Check valve, clearance and tightness,
repair if necessary
WARNING:
● When testing the spark plug, never hold the high-voltage wire of the spark plug with wet hand.
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● Make sure there is no spilled fuel outside the engine and that the spark plug isn’t dipped with
fuel.
● To prevent fire, keep sparks far away from the spark plug mount hole.
2. By using starting motor
ITEM CAUSE REMEDY
Check battery connection Incorrect connection Correct
Check battery No charge or under charge,
corrosion
Starting motor functions
Be the same as kick-starter Conduct it in the same way
normally
Check the breaker, charge
up the battery or replace it
of kick-starter
Having fulfilled all the check items above, the engine still fails to work, contact your dealer for help.
II. LOW GASOLINE ENGINE POWER OUTPUT
TROUBLE CAUSE REMEDY
When turning
throttle greater,
speed in crease
responds slow or
speedis
decreased even
engine stops
running
Ignition
system
Fuel supply
system
Incorrect ignition time
Air in fuel line or fuel line
clogged
Main oil flow hole is not
adjusted properly
In carburetor, needle valve hole
and main oil flow hole clogged
Fuel cock is clogged up
Too much carbon deposit in
combusting chamber
Too much carbon fouling in
muffler and exhaust pipe
Air cleaner is clogged up Clean air cleaner filter
Readjust ignition advance
angle
Exhaust air or dredge fuel
line
Readjust
Clean and blow to get
through
Clean, replace damaged
part
Clear away
Clear away
elemi
Intake pipe is leaking Repair or replace
Piston or cylinder or piston ring
Replace the worn
is worn
Poor
compression
Air leakage from the surface by
which cylinder block contacting
Replace cylinder gasket
with cylinder head
Too big or too small valve
Readjust it
clearance
Valve tightness is poor repair
III. GASOLINE ENGINE CANNOT RUN SMOOTHLY
TROUBLE CAUSE REMEDY
Engine is pinging
Piston, cylinder or piston ring is worn
excessively
Piston pin and piston pin hole are
worn excessively
Replace the worn
Replace piston or piston pin
Tie rod small head is worn excessively Replace tie rod
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Roller bearing for crankshaft main
shaft is worn
Engine is too hot Shoot trouble
Too much carbon deposit in
Abnormal combustion
combustion chamber
Improper gasoline brand or low
gasoline quality
There is water in float chamber Clean
Engine cannot start
because of spark
lacking
Improper spark plug electrodes
clearance
Incorrect ignition time Readjust
Something wrong with induced coil,
and so on
IV. STOP SUDDENLY WHEN RUNNING
TROUBLE CAUSE REMEDY
Fuel supply
system
Stop suddenly
when running
Ignition system
The other
Replace roller bearing
Clear away
Replace with qualified
gasoline
Adjust
Check and replace
damaged parts
Fuel is used up Refill fuel
Carburetor is clogged Check fuel line and dredge
Float is leaking Repair
Needle valve sticks
Dismantle float chamber
and criminate it
Spark plug is struck
through, or
short-circuited by carbon
Replace spark plug
deposit
Side electrode of spark
Replace spark plug
plug is dropped out
High-pressure wire is
Weld on
dropped out
Ignition coil is struck
Replace ignition coil
through to be
short-circuited
Parking wire is located
on engine body
Cylinder is pulled
damage, valve is
Find out meeting and
insulate
Repair or replace damaged
parts
dropped out
V. GASOLINE ENGINE IS EXCEESIVELY HOT
TROUBLE CAUSE REMEDY
Gasoline engine is
excessively hot
Improper ignition time Adjust ignition advance angle
properly
Insufficient fuel supply Refill engine oil
Exhaust pipe is blocked up Dredge exhaust pipe
Flow guard is leaking Repair damaged part
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Dirt or something like this fill up
noise during
among air cooling fins
Cooling fan is loosen, losing
Clear away dirt or something like
this
Reinstall well
function
The rod deformation makes
Replace tie rod
piston and cylinder bushing side
wear
Cylinder or piston or piston ring
Replace the worn
is worn, resulting in air flow
between cylinder and crankcase
Improper adjustment of engine
speed produces excessive
Readjust engine speed to proper
value by speed regulator
rotational speed
Crankshaft main bearing is burnt
Replace main bearing
out
NOTE: the gasoline should run under certain temperature. Generally, permitting temperature at the
flow guard outlet is between 80-110℃, while the temperature of the crankcase is about 60℃ under
the magneto. If temperatures surpass the limits, it is an indication that the gasoline engine is
excessively hot.
VI. THERE EXISTS ABNORMAL NOISE WHEN ENGINE RUNNING
TROUBLE CAUSE REMEDY
Abnormal noise
Piston, piston ring or cylinder is
worn
Tie rod or piston pin and piston pin
hole is worn
Replace the worn
Replace the worn
Crankshaft main bearing is worn Replace
Piston ring is broken Replace
There is an abnormal
combustion
Too much carbon deposit in
combusting chamber
Too small electrode clearance of
spark plug