YARDMAX RV170-SPRO Gasoline Engine Owner’s Manual

Gasoline Engine
Operator’s Manual

Save This Manual for Future Reference
MODEL NUMBER RV170-SPRO
SERIAL NUMBER
PURCHASE DATE
Both model numbers and serial numbers may be found on the unit. You should record both of them in a safe place for future use.

FOR YOUR SAFETY

READ AND UNDERSTAND THE ENTIRE MANUAL BEFORE OPERATING THE MACHINE
Tame the Great Outdoors·
Your newYARDMAX® engine offers quality construction and is easy and safe to operate. With proper use and care, it is designed to give you many years of dependable service.
Prepare to experience the durability to take on any job with the ease, portability, and convenience of your new engine!
Discover the YARDMAX Advantage
At YARDMAX, we understand that land ownership definitely has its privileges, but it also comes with a great deal of responsibility. When duty calls and you need to respond, will you have what it takes to tame the great outdoors?
When looking for outdoor power equipment (OPE) to get the job done right, at the right price, YARD MAX delivers the perfect combination of performance and practicality. YARD MAX has a solution that’s right for you.
MAX Performance, MAX Value, MAX Support that’s YARDMAX

• Backed by decades of proven manufacturing expertise
• Enhanced design features come standard
• Engineered for the best user experience
• Quality metal parts are used instead of plastic
• A robust warranty supports all products
• Budget-friendly prices make it practical

Up for the job? YARD MAX is.

Introduction Specifications Safety Know Your Engine Check before Operation Operation Maintenance

Introduction

DISCLAIMER
Keep this owner’s manual handy, so you can refer to it at any time.
This owner’s manual is considered a permanent part of the engine and should remain with the engine if resold.
The information and specifications included in this publication were in effect at the time of approval for printing.
READ THIS OWNER’S MANUAL CAREFULLY. Pay special attention to these symbols and any instructions that follow:
WARNING
Indicates serious injury or death will result if instructions are not followed.
DANGER
Indicates a strong possibility that serious injury or death could result if instructions are not followed.
CAUTION
Indicates a possibility that minor injury or a result if instructions are not followed.
NOTE
Indicates that equipment or property damage can result if instructions are not followed.
If a problem should arise, or if you have any questions about your engine, consult your engine dealer.
WARNING
Carefully read through this entire operator’s manual before using your new engine. Pay attention to all cautions and warnings.
ENVIRONMENTAL
Recycle unwanted materials instead of disposing of them as waste. All tools, hoses, and packaging should be resorted, taken to the local recycling center and disposed of in an environmentally safe way.
ENGINE SERIAL NUMBER
Record the engine serial number on the front cover of this manual. You will need this serial number when ordering parts, and when making technical or warranty inquiries. DISCLAIMER
YARDMAX reserves the right to discontinue, change, and improve its products at any time without notice or obligation to the purchaser. The descriptions and specifications contained in this manual were in effect at printing. The equipment described within this manual may be optional. Some illustrations may not be applicable to your unit.
SUPPORT
Have questions about your YARD MAX equipment? Call us at 847-327-0566 or 844-YARDMAX, email us at support@yardmax.com, or contact us via your favorite social media site.

SPECIFICATI0NS

MAIN SPECIFICATION

DATA ADJUSTMENT

-0.10mm

CAUTION
The specification is subject to change without notice. For further information, please contact our company dealer.
TORQUE OF IMPORTANT BOLTS

SAFETY

OWNER RESPONSIBILITIES

• The engines are designed to give safe and dependable service if operated according to instructions.
• Read and understand this owner’s manual before operating the engine.
• Failure to do so could result in personal injury or equipment damage.
• Know how to stop the engine quickly, and understand the operation of all controls. Never permit anyone to operate the engine without proper instructions.
• Do not allow children to operate the engine. Keep children and pets far away from the area of operation.

SAFETY PRECAUTIONS

DANGER
Indicate a possibility of invalid warranty and personal or equipment damage if instructions are not followed.

• Strictly set the engine according to the regulated power on the owner’s manual. Do not overload, overrun the engine, or run it with low load and at low speed in a long time.

• Use the specified grade of gasoline. The fuel should be fully deposited and filtrated before use. Keep clean the fuel filler, and change the oil periodically.

• Periodically check the installation, connection, and the degree of tightness of the fixed bolt. Tighten it if necessary.

• Periodically clean the element ofthe air cleaner, change it when necessary.

• The engine is air-cooled, so clean the radiator, wind cover, and fan in time in order to make the engine cool normally.

• The operator should be familiar with the working principle and structure of the gasoline engine, knowing how to make an emergent stop and the operation of all controlling parts. Anyone without training is forbidden to operate the engine. Keep periodical maintenance. Solve problems in time. Do not nm the engine in spite of malfunction.

• running die engine in a well-ventilated place, keep it at least one meter away from building walls or other equipment, keep away from inflammable such as gasoline, mates, and so on to avoid the possibility of fire.

• Refuel in an awell-ventilated area with the engine stopped, and in places refueling or storing gasoline, nonsmoking, and any flames or sparks.

• 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.

• Do not run the engine in airtight or ill-ventilated places.

• The inclination of a gasoline engine which indicates the included angle between crankcase cover and level is less than 26°during its running.lf that is over 26°, the oil will flow into the combustion chamber and burn with white smoke, which will cause gasoline engine has lower power and higher emission.

• Engine alone or assembled on the ultimate machine, when it tilts towards the air filter, the angle should not be beyond 26°, or oil would enter the air filter, which affects operation (engine tilts towards the muffler, the angle should be within 90°; towards the cylinder head, the angle should be within 26°).

• The engine alone or assembled on an ultimate machine, the angle it tilting backward should not be beyond 26°, or it would accelerate gasoline leakage and affect operation.

• Safe warning label: Please carefully read the warning label before operating. Our company will not assume any responsibility for a person hurt, or equipment damage caused by disregarding this warning label.

REFUEL WITH CARE
Gasoline is extremely flammable, and gasoline vapor can explode. Refuel outdoors, in a well-ventilated area, with the engine stopped. Never smoke near gasoline, and keep other flames and sparks away. Always store gasoline in an approved container. If any fuel is spilled, make sure the area is dry before starting the engine.

HOT EXHAUST

• The muffler becomes very hot during operation and remains hot for a while after stopping the engine. Be careful not to touch the muffler while it is hot. Let the engine cool before storing it indoors.
• To prevent fire hazards and to provide adequate ventilation for stationary equipment applications, keep the engine at least 3 feet (1 meter) away from building walls and other equipment during operation. Do not place flammable objects close to the engine.

CARBON MONOXIDE HAZARD
Exhaust gas contains poisonous carbon monoxide. Avoid inhalation of exhaust gas. Never run the engine in a closed garage or confined area.
OTHER EQUIPMENT
Review the instructions provided with the equipment powered by this engine for any additional safety precautions that should be observed in conjunction with engine startup, shutdown, operation, or protective apparel that may be needed to operate the equipment.

KNOW YOUR ENGINE

FEATURES AND CONTROLS

CHECK BEFORE OPERATION

IS YOUR ENGINE READY TO GO?
For your safety, and to maximize the service life of your equipment, it is very important to take a few moments before you operate the engine to check its condition. Be sure to take care of any problem you find, or have your servicing dealer correct it, before you operate the engine.
WARNING
Improperly maintaining this engine, or failing to correct a problem before operation, could cause a malfunction in which you could be seriously injured. Always perform a  reoperation inspection, and correct any problem.
Before beginning your preoperation checks, be sure the engine is level and the engine switch is in the OFF position.

CHECK THE GENERAL CONDITION OF THE ENGINE

• Look around and underneath the engine for signs of oil or gasoline leaks.
• Remove any excessive dirt or debris, especially around the muffler and recoil starter.
• Look for signs of damage.
• Check that all shields and covers are in place, and all nuts, bolts, and screws are tightened.

CHECK THE ENGINE
Check the engine oil level. Running the engine with a low oil level can cause engine damage.
The Oil Alert system (applicable engine types) will automatically stop the engine before the oil level falls below safe limits. However, to avoid the inconvenience of an unexpected shutdown, always check the engine oil level before startup.
Check the air filter. A dirty air filter will restrict airflow to the carburetor, reducing engine performance.
Check the fuel level. Starting with a full tank will help to eliminate or reduce operating interruptions for refueling.
CHECK THE EQUIPMENT POWERED BY THIS ENGINE
Review the instructions provided with the equipment powered by this engine for any precautions and procedures that should be followed before engine startup.

OPERATION

SAFE OPERATING PRECAUTIONS
Before operating the engine for the first time, please review the IMPORTANT SAFETY INFORMATION and the chapter titled BEFORE OPERATION.
WARNING
Carbon monoxide gas is toxic. Breathing it can cause unconsciousness and even kill you. Avoid any areas or actions that expose you to carbon monoxide.
Review the instructions provided with the equipment powered by this engine for any safety precautions that should be observed in conjunction with engine startup, shutdown, or operation.
STARTING THE ENGINE

1. Push down the engine switch to the ON position.
2. Starting primer bulb operation is an important operation of the starting engine. For cold starting, slightly press the primer bulb one to three times in succession and quickly pull the recoil cable grip. For hot starting, directly pull the starter cable grip.
3. Pull the starter grip lightly until resistance is felt, then, briskly pull to syncline upper 30 degrees out.

NOTE
Don’t allow the starter grip to snap back against the engine. Return it gently to prevent damage to the starter.
STOPPING THE ENGINE
Push down the engine switch to the OFF position.
CAUTION
Sudden stopping at high speed under heavy load is forbidden, otherwise, the damage will result.

MAINTENANCE

THE IMPORTANCE OF MAINTENANCE
Good maintenance is essential for safe, economical, and trouble-free operation. It will also help reduce air pollution.
WARNING
Improperly maintaining this engine, or failure to correct the problem before operation can cause a malfunction in which you can be seriously hurt or killed. Always follow the inspection and maintenance recommendations and schedules in this owner’s manual.
To help you properly care for your engine, the following pages include a maintenance schedule, routine inspection procedures, and simple maintenance procedures using basic hand tools. Other service tasks that are more difficult, or require special tools, are best handled by professionals and are normally performed by a technician or other qualified mechanic.
The maintenance schedule applies to normal operating conditions. If you operate your engine under unusual conditions, such as sustained high-load or high-temperature operation, or use in unusually wet or dusty conditions, consult your servicing dealer for recommendations applicable to your individual needs and use.

Operation & Maintenance

MAINTENANCE SAFETY PRECAUTIONS
Some of the most important safety precautions are as follows: However, we cannot warn you of every conceivable hazard that can arise in performing maintenance. Only you can decide whether or not you should perform a given task.
1. Make sure the engine is off before you begin any maintenance or repairs. This will eliminate several potential hazards:

• Carbon monoxide poisoning from engine exhaust.
  Be sure there is adequate ventilation whenever you operate the engine.

• Burns from hot parts.
  Let the engine and exhaust system cool before touching.

• Injury from moving parts.
  Do not run the engine unless instructed to do so.

2. Read the instructions before you begin, and make sure you have the tools and skills required.
3. To reduce the possibility of fire or explosion, be careful when working around gasoline. Use only a nonflammable solvent, not gasoline, to clean parts. Keep cigarettes, sparks, and flames away from all fuel-related parts.
Remember that your servicing dealer knows your engine best and is fully equipped to maintain and repair it.
To ensure the best quality and reliability, use only new, genuine parts or their equivalents for repair and replacement.

MAINTENANCE SCHEDULE

Proper maintenance is essential for safe, economical, and trouble-free operation. It also helps reduce air pollution. In order to keep your gasoline engine in good working condition, it must be periodically serviced. The following maintenance schedule and routine inspection procedures must be carefully followed.

Frequency| Every time| First
month or
10 hrs of
operation| Thereafter,
every 3
months
or 30hrs of
operation| Every 6
months or
50
hrs of
operation| Every year
or 100 hrs
of
operation
---|---|---|---|---|---
ITEM
Engine oil| Check-Refill| √| | | |
Change| | √| √| |
Air filter element| Check| √| | | |
Clean| | | √| |
Change| | | | √|
Spark plug| Clean-adjust| | | | √|
Spark arrester| Clean| | | | √|
Valve clearance| Check-adjust| | | | | √**
Fuel hose| Check| Every 2 years (change if necessary)
Cylinder head, Piston| Remove carbon deposits| Every 125 hours

• These items should be serviced by a company-authorized dealer unless you have the proper tools and are mechanically proficient.
• These items should be serviced by a mechanically proficient person or by a lour authorized servicing dealer.

CAUTION Service more frequently when used in dusty areas.
NOTE  If you frequently operate your gasoline engine under high-load or high-temperature conditions, change the engine oil every 10 hours of operation. If your gasoline engine frequently works under dusty or severe conditions, clean the air filter element every 10 hours of operation. If necessary, change the element every 25  hours of operation. Period and operation hours, the one which comes first should govern. If you accidentally missed the servicing time, do it immediately.
WARNING
Stop the engine before servicing. Put the engine on a level surface and to avoid starting, remove the spark plug cap. Never run your engine in a poorly ventilated area. Be sure to keep good ventilation in the working area. The exhaust from the engine may contain poisonous carbon monoxide, breathing it would cause shock, unconsciousness, and even death.
Fuel Check

1. Remove the fuel tank cap and check the fuel level.
2. If the level is too low, refuel the tank. Remember adding fuel, not over the fuel upper level.

WARNING
Gasoline is extremely flammable and is explosive under certain conditions. Refueling in a well-ventilation area with the engine stopped. Do ot smoke and allow flames or sparks the area where gasoline is stored or where the fuel tank is refueled. Do not overfill the fuel tank (there should be no fuel in the filling neck). After refueling, make sure the fuel tank 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.
Fuel tank capacities: 0.8L/ 27oz Only use unleaded gasoline and recommend gasoline grade 90#over.
Unleaded gasoline can reduce gasoline engine carbon deposit and prolong the exhaust system service life.
Never use contaminated gasoline or mixed gasoline with oil. Don’t allow the dust, foreign matter or water to enter into the fuel tank.
CAUTION
Fuel may damage the oil paint and plastic. Be careful not to spill fuel when refueling. Any damage due to oil spilling is not within a valid warranty.
” Light knocking” or “spark exploding” sound can be heard when the engine is overloading. It is normal. Do not worry about that.
If a “knocking” or “spam exploding” sound occurs at a steady speed under normal load, change the brand of gasoline; if such phenomena still happen, consult your dealer for help, otherwise the engine may be damaged.
When the engine is running, a continuous “knocking” or “spark exploding” sound occurring will damage engine.
“Knocking” or “spam exploding” sound from misuse will not be within the valid warranty.
ENGINE OIL LEVEL CHECK
Check the engine oil level with the engine stopped and in a level position.

1. Remove the filler cap/dipstick and wipe it clean.

2. Insert and remove the dipstick without screwing it into the filler neck. Check the oil level shown on the dipstick.

3. If the oil level is low, fill the edge of the oil filler hole with the recommended oil.

4. Screw-in the filler cap/dipstick securely.

WARNING
Running the engine with a low oil/eve/ can cause engine damage.
ENGINE OIL CHANGE
Drain the used oil while the engine is warm. Warm oil drains quickly and completely.
CAUTION
Used engine oil may cause skin cancer if repeatedly left in contact with the skin for prolonged periods. It is still advisable to thoroughly wash your hands with soap and water as soon as possible after handling used oil.

1. Place a suitable container below the engine to catch the used oil, remove the oil dipstick, drain plug, and washer.

2. Allow the used oil to drain completely, and then reinstall the drain plug, and tighten it securely.
   CAUTION
   Please dispose of used engine oil in an environmentally friendly way. We suggest you take used oil in a sealed container to your local recycling center or service station for reclamation. Do not throw it in the trash; pour it on the ground; or down a drain.

3. With the engine in a level position, fill to the outer edge of the oil filler hole with the recommended oil. Engine oil capacities: O.SL/ 17oz

4. Screw-in the filler cap/dipstick securely.

ENGINE OIL RECOMMENDATIONS
Oil is a major factor affecting performance and service life. Use 4-stroke automotive engine oil.
SAE lOW-30 is recommended for general use. Other viscosities shown in the chart may be used when the average temperature in your area is within the recommended range. The SAE oil viscosity and service classification are in the API label on the oil container. We recommend that you use API SERVICE Category SJ class or above oil.

AIR FILTER INSPECTION
Remove the air cleaner cover and inspect the filter. Clean or replace dirty filter elements. Always replace damaged filter elements. If equipped with an oil-bath air cleaner, also check the oil level.
A dirty air filter will restrict airflow to the carburetor, reducing engine performance.
If you operate the engine in very dusty areas, clean the air filter more often than specified in the MAINTENANCE SCHEDULE.
WARNING
Operating the engine without an air filter, or with a damaged air filter, will allow dirt to enter the engine, causing rapid engine wear. This type of damage is not covered by the Distributor’s Limited Warranty.

1. Remove the air cleaner housing.
2. Remove foam element or paper element, paying attention to prevent dust and foreign matter from entering into the air cleaner.
3. Check, clean, or replace damaged air cleaner parts.
4. Reinstall the air cleaner parts back.

CAUTION
Never run the engine without an air cleaner or severe wear of the engine may be resulted in. Replace the air filter element every 50 hours.
WARNING
Never clean the air cleaner element with gasoline or low flash-point detergents, or an explosion may happen.
CAUTION
Clean the foam filter with soapy water, blow the paper element with compressed air or light tap off dust, and never dry to brush .
WARNING
Gasoline is extremely flammable and explosive in certain conditions. Keep cigarettes, sparks, and fire away. After reinstalling the deposit cup, don’t start the engine until the area around is dry.
SPARK PLUG SERVICE

In order to ensure the engine normal running, a gap of the spark plug must be correct and no deposit around the spark plug.
Spark recommended using plug model TORCH: FSTC/FSRTC
WARNING
Don’t touch the muffler to avoid burning in the engine running or just stopping a moment.

1. Remove the tlie spark plug cap.
2. Clear away the dirt around the spark plug base.
3. Dismantle the spark plug with a spark plug wrench.
4. Visually check the spark plug. 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. To avoid cross-threading, first, screw in the spark plug by hand, then tighten with a spark plug wrench to compress tlie gasket.
7. If a new spark plug is used, please replace it with the same spark plug model as can as possible, and more twist 1/2 turns after compressing the gasket.
8. If reinstalling the used spark plug, just more twist 1/8-1/4 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. The incorrect heat range of the spark plug may damage the engine.

STORAGE/ TRANSPORTING

STORAGE PREPARATION
Proper storage preparation is essential for keeping your engine trouble-free and looking good. The following steps will help to keep rust and corrosion from impairing your engine’s function and appearance and will make the engine easier to start after storage.
CLEANING
If the engine has been running, allow it to cool for at least half an hour before cleaning. Clean all exterior surfaces, touch up any damaged paint, and coat other areas that may rust with a light film of oil.
CAUTION
Do not incline the engine so as to avoid fuel spill in transport. Spilled fuel or fuel vapor may ignite to cause (Ire.
If suspended for a long time, storage should be as follows:

1. The storage area is dry and free of dust.

2. Completely drain fuel out of the fuel tank and carburetor.
   WARNING
   Fuel is extremely flammable and explosive under certain conditions. Keep smoke, (Ire and spark away from the operating site.

3. Replace engine oil.

4. Remove the spark plug. Fill about a spoon of fresh engine oil onto the cylinder. Crank the engine up to distribute engine oil evenly. Reinstall the spark plug.

5. Agility pull the recoil starter rope until tlie resistance is felt. Close the choke to protect the dust from entering.

6. Cover the engine to protect dust entering.

WARNING
The length of time that gasoline can be /eft in your fuel tank and carburetor without causing functional problems will vary with such factors as gasoline blend, your storage temperatures, and whether the fuel tank is partially or completely (!/led. The air in a partially (!/led fuel tank promotes fuel deterioration. Very warm storage temperatures accelerate fuel deterioration. Gasoline will oxidize and deteriorate in storage. Deteriorated gasoline will cause hard starting, and it leaves gum deposits that clog the fuel system. As a result, If the engine is not used for more than one month, the fuel oil shall be drained thoroughly to prevent from deterioration of the fuel in the fuel system and carburetor. The failures of fuel system or engine performance arising from improper storage are beyond the scope of the warranty.
REMOVAL FROM STORAGE
Check your engine as described in the chapter CHECK BEFORE OPERATION.
If the fuel was drained during storage preparation, fill the tank with fresh gasoline. If you keep a container of gasoline for refueling, be sure that it contains only fresh gasoline. Gasoline oxidizes and deteriorates over time, causing hard starting.
If the cylinders were coated with oil during storage preparation, the engine may smoke briefly at startup. This is normal.

TRANSPORTING

If the engine has been running, allow it to cool for at least 15 minutes before loading the engine-powered equipment on the transport vehicle. A hot engine and exhaust system can burn you and can ignite some materials.
Keep the engine level when transporting to reduce the possibility of fuel leakage. Move the fuel valve lever to the OFF position.

TROUBLESHOOTING

If still can’t start, have the engine to our authorized dealer for repair.

WARNING
When testing the spark plug, never hold the high-voltage wire of the spark plug with wet hand.
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 mounting hole.
2. Gasoline Engine Power Output Insufficiency

When increasing throttle, speed increase slowly or even decrease and stop running| Fuel supply system
1. Air in the fuel line or fuel line clogged
2. Main oil flow hole is not adjusted properly
3. In a carburetor, the needle valve hole and main oil flow hole clogged
4. Fuel cock is clogged up
5. Too much carbon deposit in combusting chamber.
6. Too much car boii fouling in muffler and exhaust pipe
7. Air cleaner is closed up
8. Intake pipe is leaking| 1. Exhaust air or dredge fuel line
2. Readjust
3. Clean and blow to get through
4. Clean, replace damaged part
5. Clear away
6. Clear away
7. Clean air cleaner filter element
8. Repair or replace
Poor compression
1. Piston or cylinder or piston ring is worn
2. Air leakage from the surface by which cylinder block contacting Replace cylinder gasket with the cylinder head.
3. Too big or too small valve clearance
4. Valve tightness is poor| 1. Replace the worn
2. Replace the cylinder gasket
3. Readjust
4. Repair

3. Gasoline Engine Gan not Running Unsmoothly

2. Piston pin and piston pin hole are won excessive
3. Tie rod small head is worn excessive
4. Roller bearing for crankshaft main shaft is worn| 1. Replace the worn
2. Replace piston or piston pin
3. Replace tie rod
4. Replace roller bearing
Abnormal combustion| 1. Engine is too hot
2. Too much carbon deposit in the combustion chamber
3. Improper gasoline brand or low gasoline quality| 1. Shoot trouble
2. Clear away
3. Replace with qualified gasoline
Spark lacking| 1. There is water in the float chamber
2. Improper spark plug electrodes clearance
3. Something wrong with an induced coil, and so on| 1. Clean
2. Adjust
3. Check and replace damaged parts

4. Stop Suddenly When Running

1. Fuel is finished
2. Carburetor is clogged
3. Float chamber is leaking
4. Needle valve is a stuck Ignition system| 1. Refill fue
2. Check fuel line and dredge
3. Repair
4. Dismantle feat chamber and eliminate it
1. Spark plug is punctured, or short
circuited by carbon deposit
2. Side electrode of the spark plug is dropped out
3. High-tension wire is dropped out
4. Ignition coil is punctured or shortcircuited
5. Parking wire is located on the engine body| 1. Replace the spark plug
2. Replace the spark plug
3. Weldon
4. Replace ignition coil
5. Find out meeting and insulate
Stop suddenly when running| The other
1. Cylinder is seriously scored and valve
dropped out| 1. Repair or replace damaged parts

5. Gasoline Engine Is Overheat

Gasoline engine is
overheat| 1. Oil insufficient or wrong oil ratio in the gasoline
2. Exhaust pipe blocked up
3. Shroud leaking
4. Cooling fins blocked by foreign matter
5. Connection rod deformation to make piston and cylinder bushing side wear
6. Cylinder or piston or piston ring is worn
to make hunting between cylinder and crankcase
7. Improper adjustment of engine governor
to produce speed high
8. Crankshaft main bearing burnt out| 1. Refill engine oil
2. Clean exhaust pipe
3. Repair damaged part
4. Clear cooling fins
5. Replace the connection rod
6. Replace the won parts
7. Readjust engine governor
8. Replace the main bearing

**** CAUTION
The gasoline engine should be kept at about 80 -110°C temperature around the outlet of the shroud. If the temperature is too high, it will indicate the gasoline engine overheating.

2. Connection rod or piston pin and piston pinhole are worn
3. Crankshaft main neck is worn
4. Piston ring is broken| 1. Replace the worn part
2. Replace the worn part
3. Replace bearing
4. Replace piston ring
Metal beating sound when abnormal combustion occurs| 1. Too much carbon deposit in combusting chamber
2. ImproPer nuclei brand
3. Engine is overheat| 1. Clear away carbon deposit
2. Replace fuel
3. Find a cause and eliminate it
The other| 1. Improper valve clearance
2. Flywheel is not connected with
crankshaft tightly| 1. Readjust valve clearance properly
2. Connect tightly

WIRING DIAGRAMS

EASY WORN PARIS AND ACCESSORIES LIS

Easy worn parts list

• Cylinder head cover gasket
• Cylinder head gasket
• Spark plug
• Oil sealing
• Breath groove gasket
• Recoil starter
• Carburetor gasket
• Carburetor insulation gasket
• Insulation plate gasket
• Exhaust vent gasket

KIT HIGH ALTITUDE REPLACEMENT FOR EPAIII ENGINES

3000-6000ft/6000-8000ft of elevation
At high altitudes, the standard carburetor air-fuel mixture will be too rich. The performance will decrease and fuel consumption will increase. A very rich mixture will also foul the spark plug and cause a hard starting. Operation at an altitude that differs from that at which this engine was certified, for extended periods of time, may increase emissions.
The fuel system on this engine/equipment may be influenced by operation at higher altitudes. Proper operation can be ensured by installing an altitude kit when required. See the table below to determine when an altitude kit is required. Operating this engine/equipment without the proper altitude kit installed may increase the engine’s emissions and decrease fuel economy and performance. Kits may be obtained from any dealer and should be installed by a qualified individual.

• Engine, Generator Set, Pressure Washer, Walk-Behind Lawnmower, Compressor, Pump, Tiller etc. ** Elevation above sea level.

  • This high-altitude jet is to be used at elevations above 3000 feet.
  • At elevations above 8000 feet, the engine/equipment may experience decreased performance, even with the high altitude kit.
  • If a carburetor is replaced, the proper high altitude kit jet will need to be installed into the replacement carburetor.

WARNING
To prevent serious injury from frre: Follow the kit procedures in a well- ventilated area away from ignition sources. If the engine is hot from use, shut the engine off and wait for it to cool before proceeding.
NOTE
The warranty may be void if necessary adjustments are not made for high altitude use

EXHAUST CONTROL SYSTEM SERVICE

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 with each other to make smoke while carbon monoxide is toxic, so exhaust control of them is very important.
The company decreases exhaust emissions by introducing poor-fuel carburetors and other devices into the engine to solve the problem.
To keep the exhaust of your engine within 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 used under heavy load, in dusty or wet circumstances or in high temperature, service of the engine should be done more often.
2. Replacing Parts
To ensure the best quality and reliability, use only new genuine our company parts or their equivalents for repair and replacement.
3. Tampering and Altering
Tampering with or altering the emission control system may increase emissions beyond the legal limit. Among those acts that constitute tampering are:

1. Removal or alteration of any pa art of the intake, fuel. or exhaust systems.
2. Altering or defeating the governor linkage or speed-adjusting mechanism to cause the engine to operate outside its design parameters.

4. Problems Affecting Exhaust Emissions

1. Difficult starting or difficult stopping.
2. Unstable idle speed.
3. Give off black smoke or consume too much fuel.
4. Poor ignition sparks or sparks returned. S)Too early ignition.

CALIFORNIA AND FEDERAL EXHAUST AND EVAPORATIVE EMISSIONS CONTROL WARRANTY STATEMENT

YOUR WARRANTY RIGHTS AND OBLIGATIONS

• The California Air Resources Board, the United States Environmental Protection Agency, and YARDMAX POWER PRODUCTS (YARDMAX), are pleased to explain the exhaust and evaporative emissions (“emissions”) control system warranty on your 2022/2023 small off-road engine/ equipment. In California, new equipment that use small offroad engines must be designed, built, and equipped to meet the State’s stringent anti-smog standards. YARDMAX must warrant the emissions control system on your small off-road engine/equipment for the period listed below provided there has been no abuse, neglect or improper maintenance of your small off-road engine/equipment leading to the failure of the emissions control system.
• Your emissions control system may include parts such as the carburetor or fuel-injection system, the ignition system, catalytic converter, fuel tanks, fuel lines (for liquid fuel and fuel vapors), fuel caps, valves, canisters, filters, clamps and other associated components. Also included may be hoses, belts, connectors, and other emission-related assemblies.
•  Where a warrantable condition exists, YARDMAX will repair your small off-road engine/equipment at no cost to you including diagnosis, parts and labor.

MANUFACTURER’S WARRANTY COVERAGE
The exhaust and evaporative emissions control system on your small off-road engine/equipment is warranted for two years. If any emissions-related part on your small off-road engine/equipment is defective, the part will be repaired or replaced by YARDMAX.
OWNER’S WARRANTY RESPONSIBILITIES

• As the small off-road engine/equipment owner, you are responsible for the performance of the required maintenance listed in your owner’s manual. YARDMAX recommends that you retain all receipts covering maintenance on your small offroad engine/equipment, but YARDMAX cannot deny warranty coverage solely for the lack of receipts or for your failure to ensure the performance of all scheduled maintenance.
• As the small off-road engine/equipment owner, you should however be aware that YARDMAX may deny you warranty coverage if your small off-road engine/equipment or a part has failed due to abuse, neglect, improper maintenance or unapproved modifications.
• You are responsible for presenting your small off-road engine/ equipment to a YARDMAX distribution center or service center as soon as the problem exists. The warranty repairs shall be completed in a reasonable amount of time, not to exceed 30 days.
•  If you have any questions regarding your warranty rights and responsibilities, you should contact YARDMAX POWER PRODUCTS. at 847-327-0566 or 844-YARDMAX”. The nationwide service E_mail is support@yardmax.com.

DEFECTS WARRANTY REQUIREMENTS

• The warranty period begins on the date the small off-road engine/equipment is delivered to an ultimate purchaser.

• General Emissions Warranty Coverage. YARDMAX warrants to the ultimate purchaser and each subsequent owner that the engine or equipment is:
  (1) Designed, built, and equipped so as to conform with all applicable regulations adopted by the Air Resources Board; and
  (2) Free from defects in materials and workmanship that causes the failure of a warranted part for a period of two years.

• The warranty on emission-related parts will be interpreted as follows:

1. Any warranted part that is not scheduled for replacement as required maintenance in the written instructions must be warranted for the warranty period defined in Subsection (b)(2). If any such part fails during the period of warranty coverage, it must be repaired or replaced by YARDMAX according to Subsection (4) below. Any such part repaired or replaced under the warranty must be warranted for the remaining warranty period.
2. Any warranted part that is scheduled only for regular inspection in the written instructions must be warranted for the warranty period defined in Subsection (b)(2). A statement in such written instructions to the effect of”repair or replace as necessary” shall advise owners ofthe warranty coverage for emissions-related parts. Replacement within the warranty period is covered by the warranty and will not reduce the period of warranty coverage. Any such part repaired or replaced under warranty must be warranted for the remaining warranty period.
3.  Any warranted part that is scheduled for replacement as required maintenance in the written instructions must be warranted for the period of time prior to the first scheduled replacement point for that part. If the part fails prior to the first scheduled replacement, the part must be repaired or replaced by YARDMAX according to Subsection (4) below. Any such part repaired or replaced under warranty must be warranted for the remainder of the period prior to the first scheduled replacement point for the part.
4. Repair or replacement of any warranted part under the warranty provisions must be performed at no charge to the owner at a warranty station.
5. Notwithstanding the provisions of Subsection (4)above, warranty services or repairs must be provided at distribution centers that are franchised to service the subject engine/equipment.
6. The owner must not be charged for diagnostic labor that leads to the determination that a warranted part is in fact defective, provided that such diagnostic work is performed at a warranty station.
7. YARDMAX is liable for damages to other engine/equipment components proximately caused by a failure under warranty of any warranted part.
8. Throughout the emissions control system’s warranty period set out in subsection (b)(2), YARDMAX must maintain a supply of warranted parts sufficient to meet the expected demand for such parts and must obtain additional parts if that supply is exhausted.
9. Manufacturer-approved replacement parts that do not increase the exhaust or evaporative emissions of the engine or emissions control system must be used in the performance of any warranty maintenance or repairs and must be provided without charge to the owner. Such use will not reduce the warranty obligations of YARDMAX.
10. Add-on or modified parts that are not exempted by the Air Resources Board may not be used. The use of any nonexempted add-on or modified parts will be grounds for disallowing a warranty claim. YARDMAX will not be liable to warrant failures of warranted parts caused by the use of a non-exempted add-on or modified part.
11. YARDMAX issuing the warranty shall provide any documents that describe the warranty procedures or policies within five working days of request by the Executive Officer.

Emission Warranty Parts List for Exhaust

1. Fuel Metering System
   (i) Carburetor and internal parts (and/or pressure regulator
   or fuel injection system).
   (ii) Air/fuel ratio feedback and control system.
   (iii) Cold start enrichment system.

2. Air Induction System
   (i) Controlled hot air intake system.
   (ii) Intake manifold.
   (iii) Air filter.

3. Ignition System
   (i) Spark Plugs.
   (ii) Magneto or electronic ignition system.
   (iii) Spark advance/retard system.

4. Exhaust Gas Recirculation (EGR) System
   (i) EGR valve body, and carburetor spacer if applicable.
   (ii) EGR rate feedback and control system.

5. Air Injection System
   (i) Air pump or pulse valve.
   (ii) Valves affecting distribution of flow.
   (iii) Distribution manifold.

6. Catalyst or Thermal Reactor System
   (i) Catalytic converter.
   (ii) Thermal reactor
   (iii) Exhaust manifold.

7. Particulate Controls
   (i) Traps, filters, precipitators, and any other device used to capture particulate emissions.

8. Miscellaneous Items Used in Above Systems
   (i) Electronic controls.
   (ii) Vacuum, temperature, and time-sensitive valves and switches.
   (iii) Hoses, belts, connectors, and assemblies.

• Emission Warranty Parts List for Evap

1. Fuel Tank
2. Fuel Cap
3.  Fuel Lines (for liquid fuel and fuel vapors)
4. Fuel Line Fittings
5. Camps*
6.  Pressure Relief Valves*
7. Control Valves*
8. Control Solenoids*
9. Electronic Controls*
10. Vacuum Control Diaphragms*
11. Control Cables*
12. Control Linkages*
13. Purge Valves*
14. Gaskets*
15. LiquidNapor Separator
16. Carbon Canister
17. Canister Mounting Brackets
18. Carburetor Purge Port Connector

• Note: As they relate to the evaporative emission control system.
  • YARDMAX will furnish with each new small off-road engine/ equipment written instructions for the maintenance and use of the engine/equipment by the owner.
  California And Federal Exhaust And Evaporative Emissions Control Warranty Statement

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