honda lpg (liquefied petroleum gas) engines

8/13/2019 Honda LPG (liquefied petroleum gas) Engines

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Owners Manual

GX270GX390LPG-Fueled Engine


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Keep this owners manual handy, so you can refer to it at any time.

This owners manual is considered a permanent part of the engine andshould remain with the engine if resold.

The information and specifications included in this publication were ineffect at the time of approval for printing. Illustrations are based on theGX270 LPG. Honda Motor Co., Ltd. reserves the right, however, todiscontinue or change specifications or design at any time withoutnotice and without incurring any obligation whatever. No part of thispublication may be reproduced without written permission.

The engine exhaust from this productcontains chemicals known to the State

of California to cause cancer, birthdefects or other reproductive harm.


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1

INTRODUCTION

Congratulations on your selection of a Honda engine. We are certainyou will be pleased with your purchase of one of the finest engines onthe market.

We want to help you get the best results from your new engine and tooperate it safely. This manual contains the information on how to dothat; please read it carefully.

As you read this manual, you will find information preceded by asymbol. That information is intended to help you avoid

damage to your engine, other property, or the environment.

We suggest you read the warranty policy to fully understand itscoverage and your responsibilities of ownership. The warranty policyis a separate document that should have been given to you by yourdealer.

When your engine needs scheduled maintenance, keep in mind thatyour Honda servicing dealer is specially trained in servicing Hondaengines. Your Honda servicing dealer is dedicated to your satisfactionand will be pleased to answer your questions and concerns.

Best Wishes,Honda Motor Co., Ltd.


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2

INTRODUCTION

A FEW WORDS ABOUT SAFETY

Safety Labels

Safety Messages

Safety Headings

Safety Section

Instructions

Your safety and the safety of others are very important. And using thisengine safely is an important responsibility.

To help you make informed decisions about safety, we have providedoperating procedures and other information on labels and in thismanual. This information alerts you to potential hazards that couldhurt you or others.

Of course, it is not practical or possible to warn you about all thehazards associated with operating or maintaining an engine. You mustuse your own good judgment.

You will find important safety information in a variety of forms,including:

on the engine.

preceded by a safety alert symbol and oneof three signal words, DANGER, WARNING, or CAUTION.

These signal words mean:

You WILL be KILLED or SERIOUSLY HURT ifyou dont follow instructions.

You CAN be KILLED or SERIOUSLY HURT ifyou dont follow instructions.

You CAN be HURT if you dont followinstructions.

such as IMPORTANT SAFETY INFORMATION.

such as ENGINE SAFETY.

how to use this engine correctly and safely.

This entire book is filled with important safety information pleaseread it carefully.


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3

CONTENTS

.......................................................................................ENGINE SAFETY . 5................................................IMPORTANT SAFETY INFORMATION . 5

........................................................................CONTROLS & FEATURES . 7

............................................COMPONENT & CONTROL LOCATIONS . 7............................................................................................CONTROLS . 8

....................................................................................Engine Switch . 8.......................................................................................Choke Lever . 9

..................................................................................Throttle Lever . 10...........................................................................Recoil Starter Grip . 10

...........................................................................................FEATURES . 11.................................Oil Alert System (applicable engine types) . 11

.............................................................................BEFORE OPERATION . 12.....................................................IS YOUR ENGINE READY TO GO? . 12

..................................Check the General Condition of the Engine . 12.............................................................................Check the Engine . 13

............................Check the Equipment Powered by This Engine . 13

............................................................................................OPERATION . 14...................................................SAFE OPERATING PRECAUTIONS . 14

....................................................................STARTING THE ENGINE . 14....................................................................STOPPING THE ENGINE . 18...................................................................SETTING ENGINE SPEED . 19

.....................................................SERVICING YOUR HONDA ENGINE . 20............................................THE IMPORTANCE OF MAINTENANCE . 20

....................................................................MAINTENANCE SAFETY . 21..............................................................MAINTENANCE SCHEDULE . 22.............................................................FUEL RECOMMENDATIONS . 23

................................................................ENGINE OIL LEVEL CHECK . 24.........................................................................ENGINE OIL CHANGE . 25

..................................................ENGINE OIL RECOMMENDATIONS . 26....................................................................AIR FILTER INSPECTION . 27

......................................................................AIR CLEANER SERVICE . 28.......................................................................SPARK PLUG SERVICE . 30

...............................................................IDLE SPEED ADJUSTMENT . 31.....................................SPARK ARRESTER SERVICE (optional part) . 32


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CONTENTS

.........................................................HELPFUL TIPS & SUGGESTIONS . 33...................................................................STORING YOUR ENGINE . 33

........................................................................Storage Preparation . 33

........................................................................Storage Precautions . 34

...................................................................Removal From Storage . 35.................................................................................TRANSPORTING . 36

.....................................TAKING CARE OF UNEXPECTED PROBLEMS . 37.................................................................ENGINE WILL NOT START . 37

.....................................................................ENGINE LACKS POWER . 37

........................................TECHNICAL & CONSUMER INFORMATION . 38...............................................................TECHNICAL INFORMATION . 38

..................................................................Serial Number Location . 38.................................................................Remote Control Linkage . 39

...................Carburetor Modification for High Altitude Operation . 40..........................................Emission Control System Information . 41

...........................................................................................Air Index . 43..................................................................................Specifications . 44

...............................................................................Wiring Diagram . 45..............................................................CONSUMER INFORMATION . 46

.........................................................................Honda Publications . 46........................................................Warranty Service Information . 47

............................QUICK REFERENCE INFORMATION . Inside back cover


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5

ENGINE SAFETY

IMPORTANT SAFETY INFORMATION

Owner Responsibilities

Refuel With Care

Hot Exhaust

Most accidents with engines can be prevented if you follow allinstructions in this manual and on the engine. Some of the most

common hazards are discussed below, along with the best way toprotect yourself and others.

Honda engines are designed to give safe and dependable service ifoperated according to instructions. Read and understand thisowners manual before operating the engine. Failure to do so couldresult in personal injury or equipment damage.

Know how to stop the engine quickly, and understand the operationof all controls. Never permit anyone to operate the engine withoutproper instructions.

Do not allow children to operate the engine. Keep children and petsaway from the area of operation.

LPG is extremely flammable, and LPG can explode. Refuel outdoors, ina well-ventilated area, with the engine stopped. Never smoke near LPG,and keep other flames and sparks away.

The muffler becomes very hot during operation and remains hot for

a while after stopping the engine. Be careful not to touch the mufflerwhile it is hot. Let the engine cool before storing it indoors.

To prevent fire hazards and to provide adequate ventilation forstationary equipment applications, keep the engine at least 3 feet (1meter) away from building walls and other equipment duringoperation. Do not place flammable objects close to the engine.


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6

ENGINE SAFETY

Other Equipment

Carbon Monoxide Hazard

Review the instructions provided with the equipment powered by thisengine for any additional safety precautions that should be observedin conjunction with engine startup, shutdown, or operation, orprotective apparel that may be needed to operate the equipment.

Exhaust gas contains poisonous carbon monoxide. Avoid inhalation ofexhaust gas. Never run the engine in a closed garage or confined area.


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7

COMPONENT & CONTROL LOCATIONS

CONTROLS & FEATURES

MUFFLER AIR CLEANER

THROTTLE LEVER

RECOIL STARTER

SPARK PLUG

OIL DRAIN PLUG

ENGINE SWITCH

CHOKE LEVER

OIL FILLER CAP

STARTER GRIP


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8

CONTROLS & FEATURES

CONTROLS

Engine Switch

ENGINE SWITCH

OFF

ON

The engine switch enables and disables the ignition system.

The engine switch must be in the ON position for the engine to run.

Turning the engine switch to the OFF position stops the engine.


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9

CONTROLS & FEATURES

Choke Lever

CHOKE LEVER

OOPPEENNCLLOOSSEEDD

The choke lever opens and closes the choke valve in the carburetor.

Some engine applications use a remotely-mounted choke controlrather than the engine-mounted choke lever shown here.

The CLOSED position creates a vacuum to help the LPG to flow intothe engine during starting.

The OPEN position removes the vacuum after the engine has startedand can produced its own vacuum.


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10

CONTROLS & FEATURES

Throttle Lever

Recoil Starter Grip

THROTTLE LEVER

SLOWFASSTT

STARTER GRIP

The throttle lever controls engine speed.

Moving the throttle lever in the directions shown makes the enginerun faster or slower.

Some engine applications use a remotely-mounted throttle controlrather than the engine-mounted throttle lever shown here.

Pulling the starter grip operates the recoil starter to crank the engine.


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11

CONTROLS & FEATURES

FEATURES

Oil Alert System (applicable engine types)

If the engine stops and will not restart, check the engine oil level (page) before troubleshooting in other areas.

The Oil Alert system is designed to prevent engine damage causedby an insufficient amount of oil in the crankcase. Before the oil level inthe crankcase can fall below a safe limit, the Oil Alert system willautomatically stop the engine (the ignition switch will remain in theON position).

24


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12

BEFORE OPERATION

IS YOUR ENGINE READY TO GO?

Check the General Condition of the Engine

For your safety, and to maximize the service life of your equipment, itis very important to take a few moments before you operate the

engine to check its condition. Be sure to take care of any problem youfind, or have your servicing dealer correct it, before you operate theengine.

Improperly maintaining this engine,or failing to correct a problembefore operation, could cause amalfunction in which you could beseriously injured.

Always perform a preoperationinspection before each operation,and correct any problem.

Before beginning your preoperation checks, be sure the engine is leveland the engine switch is in the OFF position.

Remove any excessive dirt or debris, especially around the mufflerand recoil starter.

Look for signs of damage.

Check that all shields and covers are in place, and all nuts, bolts, andscrews are tightened.

Look and smell around and underneath the engine for signs of oil orLPG leaks.


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13

BEFORE OPERATION

Check the Engine

Check the Equipment Powered by This Engine

Check the engine oil level (see page ). Running the engine with alow oil level can cause engine damage.

The Oil Alert system (applicable engine types) will automaticallystop the engine before the oil level falls below safe limits. However,to avoid the inconvenience of an unexpected shutdown, alwayscheck the engine oil level before startup.

Check the air filter (see page ). A dirty air filter will restrict air flowto the carburetor, reducing engine performance.

Review the instructions provided with the equipment powered by thisengine for any precautions and procedures that should be followedbefore engine startup.

24

27


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14

OPERATION

SAFE OPERATING PRECAUTIONS

STARTING THE ENGINE

Before operating the engine for the first time, please review theIMPORTANT SAFETY INFORMATIONon page and the chapter titled

BEFORE OPERATION.

Review the instructions provided with the equipment powered by thisengine for any safety precautions that should be observed inconjunction with engine startup, shutdown, or operation.

Carbon monoxide gas is toxic.Breathing it can causeunconsciousness and even kill you.

Avoid any areas or actions thatexpose you to carbon monoxide.

Turn the fuel valve to the OPEN or ON position at the source beforeattempting to start the engine.

5

1.


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15

OPERATION

CHOKE LEVER

THROTTLE LEVER

SSLLOOWW

CLLOOSSEEDD

Move the choke lever to the CLOSED position.

Always use the choke when starting the engine.

Some engine applications use a remotely-mounted choke controlrather than the engine-mounted choke lever shown here.

Move the throttle lever away from the SLOW position, about 1/3 ofthe way toward the FAST position.


2.

3.


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16

OPERATION

ON

ENGINE SWITCH

STARTER GRIP

Turn the engine switch to the ON position.

Operate the starter.

Pull the starter grip lightly until you feel resistance, then pull briskly.Return the starter grip gently.

4.

5.


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OPERATION

CHOKE LEVER

OPEN

Move the choke lever to the OPEN position after the engine hasstarted.

6.


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OPERATION

STOPPING THE ENGINE

THROTTLE LEVER

ENGINE SWITCH

OFF

SLOW

To stop the engine in an emergency, simply turn the engine switch tothe OFF position. Under normal conditions, use the following

procedure.

Move the throttle lever to the SLOW position.


Turn the fuel valve to the CLOSED or OFF position at the source.

Turn the engine switch to the OFF position.

1.

2.

3.


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OPERATION

SETTING ENGINE SPEED

THROTTLE LEVER

SLOWFASSTT

Position the throttle lever for the desired engine speed.


For engine speed recommendations, refer to the instructions providedwith the equipment powered by this engine.


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20

SERVICING YOUR ENGINE

THE IMPORTANCE OF MAINTENANCE

Maintenance, replacement or repair of emission control devices andsystems may be done by any engine repair establishment orindividual, using parts that are certified to EPA standards.

Good maintenance is essential for safe, economical, and trouble-freeoperation. It will also help reduce air pollution.

Improperly maintaining this engine,or failure to correct a problembefore operation, can cause amalfunction in which you can beseriously hurt or killed.

Always follow the inspection andmaintenance recommendations andschedules in this owners manual.

To help you properly care for your engine, the following pages includea maintenance schedule, routine inspection procedures, and simple

maintenance procedures using basic hand tools. Other service tasksthat are more difficult, or require special tools, are best handled byprofessionals and are normally performed by a Honda technician orother qualified mechanic.

The maintenance schedule applies to normal operating conditions. Ifyou operate your engine under unusual conditions, such as sustainedhigh-load or high-temperature operation, or use in unusually wet ordusty conditions, consult your servicing dealer for recommendations

applicable to your individual needs and use.


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MAINTENANCE SAFETY

Safety Precautions

Carbon monoxide poisoning from engine exhaust.

Burns from hot parts.

Injury from moving parts.

Some of the most important safety precautions follow. However, wecannot warn you of every conceivable hazard that can arise in

performing maintenance. Only you can decide whether or not youshould perform a given task.

Failure to properly followmaintenance instructions andprecautions can cause you to beseriously hurt or killed.

Always follow the procedures andprecautions in the owners manual.

Make sure the engine is off before you begin any maintenance orrepairs. This will eliminate several potential hazards:

Be sure there is adequate ventilation whenever you operate theengine.

Let the engine and exhaust system cool before touching.

Do not run the engine unless instructed to do so.

Read the instructions before you begin, and make sure you have thetools and skills required.

Remember that your servicing dealer knows your engine best and isfully equipped to maintain and repair it.

To ensure the best quality and reliability, use only new, genuineHonda parts or their equivalents for repair and replacement.

To reduce the possibility of fire or explosion, be careful whenworking around LPG. Keep cigarettes, sparks and flames away fromall fuel-related parts.


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MAINTENANCE SCHEDULE

For commercial use, log hours of operation to determine propermaintenance intervals.

These items should be serviced by your servicing dealer, unlessyou have the proper tools and are mechanically proficient. Referto Honda shop manual for service procedures.

Service more frequently when used in dusty areas.

Replace the paper element type only.

Emission-related items.

(1)

(2)

(3)

( )

Engine oil

(LPG model)

Reduction gear oil

(Equipped model)

Air filter

Sediment cup

Spark plug

Spark arrester

(optional parts)

Idle speed

Valve clearance

Combustion chamberFuel tube (LPG model)

Fuel tube

Each

useITEM

First

month

or

20 Hrs.

Every

3 months

or

50 Hrs.

Every

6 months

or

100 Hrs.

Refer

to

page

Check level

Change

Clean

Replace

Check-adjust

(2)

(2)

(1)

24

25

27

28

30

32

31

Every

year

or

200 Hrs.

Check

Clean

Clean

Replace

Clean

Check

Check level

Change

REGULAR SERVICE PERIOD (3)

After every 250 Hrs (2)

Check-adjust

Check-adjust

Perform at every indicated

month or operating hour interval,

whichever comes first.

( )

Check Every 2 years (Replace if necessary) (2)


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FUEL RECOMMENDATIONS

Use LPG with a propane content of 95% or higher.

This engine is certified to operate on LPG only.

Occasionally you may hear a light spark knock or pinging(metallic rapping noise) while operating under heavy loads. This is nocause for concern.

If spark knock or pinging occurs at a steady engine speed, undernormal load, change brands of LPG. If spark knock or pinging persists,see an authorized Honda servicing dealer.

Running the engine with persistent spark knock or pinging can causeengine damage.

Running the engine with persistent spark knock or pinging is misuse,and theDistributors Limited Warranty does not cover parts damagedby misuse.


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ENGINE OIL LEVEL CHECK

LOWER LIMIT

UPPER LIMIT

FILLER CAP/DIPSTICK

Check the engine oil level with the engine stopped and in a levelposition.

Running the engine with a low oil level can cause engine damage.

The Oil Alert system (applicable engine types) will automatically stopthe engine before the oil level falls below safe limit. However, to avoidthe inconvenience of an unexpected shutdown, always check theengine oil level before startup.

Remove the filler cap/dipstick and wipe it clean.

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

If the oil level is low, fill to the edge of the oil filler hole with therecommended oil (see page 26).

Screw in the filler cap/dipstick securely.

1.

2.

3.

4.


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ENGINEOIL CHANGE

FILLER CAP/DIPSTICK

OIL LEVEL

DRAINPLUG

Drain the used oil while the engine is warm. Warm oil drains quicklyand completely.

1.16 US qt (1.10 )

Running the engine with a low oil level can cause engine damage.

The Oil Alert system (applicable engine types) will automaticallystop the engine before the oil level falls below the safe limit.However, to avoid the inconvenience of an unexpected shutdown,fill to the upper limit, and check the oil level regularly.

Place a suitable container below the engine to catch the used oil,then remove the filler cap/dipstick and the drain plug.

Allow the used oil to drain completely, then reinstall the drain plug,and tighten it securely.

Please dispose of used motor oil in a manner that is compatible withthe environment. We suggest you take used oil in a sealed containerto your local recycling center or service station for reclamation. Donot throw it in the trash, pour it on the ground, or down a drain.

With the engine in a level position, fill to the outer edge of the oilfiller hole with the recommended oil (see page 26).

Screw in the filler cap/dipstick securely.

1.

2.

Engine oil capacity:

3.

4.


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ENGINE OIL RECOMMENDATIONS

Oil is a major factor affecting performance and service life. Use4-stroke automotive detergent oil that is designed for engines

operating on LPG.

For operation in temperatures below 32F (0C), 5W-30 synthetic oilmay be used for easier starting. Do not use 5W-30 synthetic oil whenthe air temperature is above 32F (0C).

Do not use multigrade mineral-based oils. The use of multigrademineral-based oils may result in premature engine wear and/or

damage.

SAE 30 (API service classification SJ) is recommended for general use.The following are examples of oils that meet Hondas requirements forLPG-fueled engines:

Pennzoil HD 30Valvoline HPO 30Castrol HD 30


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AIR FILTER INSPECTION

PAPERFILTERELEMENT

FOAMFILTERELEMENT

Remove the air cleaner cover and inspect the filter elements. Clean orreplace dirty filter elements. Always replace damaged filter elements.

Refer to page for instructions that apply to the air cleaner and filterservice.

28


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AIR CLEANER SERVICE

AIRCLEANERCOVER

PAPER

FILTERELEMENT

FOAMFILTERELEMENT

GASKET

WINGNUTS

A dirty air filter will restrict air flow to the carburetor, reducing engineperformance. If you operate the engine in very dusty areas, clean the

air filter more often than specified in the MAINTENANCE SCHEDULE.

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 typeof damage is not covered by theDistributors Limited Warranty.

Remove the wing nut from theair cleaner cover, and removethe cover.

Remove the wing nut from theair filter, and remove the filter.

Remove the foam filter from thepaper filter.

Inspect both air filter elements,and replace them if they aredamaged. Always replace thepaper air filter element at thescheduled interval (see page22).

Clean the air filter elements ifthey are to be reused.

1.

2.

3.

4.

5.


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SPARK PLUG SERVICE

SPARK PLUG WRENCH

0.028 0.031 in

(0.70 0.80 mm)

BPR6ESW20EPR-U

An incorrect spark plug can cause engine damage.

Disconnect the spark plug cap, and remove any dirt from around thespark plug area.

Remove the spark plug with a 13/16-inch spark plug wrench.

Inspect the spark plug. Replace itif the electrodes are worn, or if theinsulator is cracked or chipped.

Clean the spark plug with a wirebrush if you are going to reuse it.

Measure the spark plug electrodegap with a suitable gauge. Thega p sh ou ld be 0.028 0.031 in(0.70 0.80 mm). Correct the gap,if necessary, by carefully bendingthe side electrode.

Install the spark plug carefully, byhand, to avoid cross-threading.

1.

2.

Recommended spark plugs: (NGK)

3.

4.

5.

(DENSO)


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IDLE SPEED ADJUSTMENT

THROTTLE STOP SCREW

A loose spark plug can overheat and damage the engine.Overtightening the spark plug can damage the threads in thecylinder head.

After the spark plug seats, tighten with a 13/16-inch spark plugwrench to compress the washer.

If reinstalling the used spark plug, tighten 1/8 1/4 turn after the

spark plug seats.

If installing a new spark plug, tighten 1/2 turn after the spark plugseats.

Attach the spark plug cap.

Start the engine outdoors, and allow it to warm up to operatingtemperature.

Move the throttle lever to its slowest position.

Turn the throttle stop screw to obtain the standard idle speed.

6.

7.

1.

2.

3.

Standard idle speed: 1,400 rpm200150


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SPARK ARRESTER SERVICE (optional equipment)

5 mm SCREWS

4 mm SCREW

4 mmSCREWS

8 mm NUTS MUFFLERSPARK ARRESTER

EXHAUSTDEFLECTOR

SPARKARRESTER

MUFFLERPROTECTOR

SCREEN

Your engine is not factory-equipped with a spark arrester. In someareas, it is illegal to operate an engine without a spark arrester. Check

local laws and regulations. A spark arrester is available fromauthorized Honda servicing dealers.

The spark arrester must be serviced every 100 hours to keep itfunctioning as designed.

If the engine has been running, the muffler will be very hot. Allow themuffler to cool before servicing the spark arrester.

Remove the two 8 mm nuts and remove the muffler from thecylinder.Remove the three 4 mm screws from the exhaust deflector, andremove the deflector.Remove the four 5 mm screws from the muffler protector andremove the muffler protector.Remove the 4 mm screws from the spark arrester, and remove thespark arrester from the muffler.

Use a brush to remove carbon depositsfrom the spark arrester screen. Becareful to avoid damaging the screen.The spark arrester must be free ofbreaks and holes. Replace the sparkarrester if it is damaged.Install the spark arrester, muffler protector, exhaust deflector, andmuffler in the reverse order of disassembly.

1.

2.

3.

4.

5.

6.


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33

HELPFUL TIPS & SUGGESTIONS

STORING YOUR ENGINE

Storage Preparation

Cleaning

Proper storage preparation is essential for keeping your enginetroublefree and looking good. The following steps will help to keeprust and corrosion from impairing your engines function andappearance, and will make the engine easier to start when you use itagain.

If the engine has been running, allow it to cool for at least half an hourbefore cleaning. Clean all exterior surfaces, touch up any damagedpaint, and coat other areas that may rust with a light film of oil.

Using a garden hose or pressure washing equipment can forcewater into the air cleaner or muffler opening. Water in the air cleanerwill soak the air filter, and water that passes through the air filter ormuffler can enter the cylinder, causing damage.

Water contacting a hot engine can cause damage. If the engine hasbeen running, allow it to cool for at least half an hour beforewashing.


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34


Engine Oil

Storage Precautions

Engine Cylinder

Align notch on pulley

with hole at top of cover.

Select a well-ventilated storage area away from any appliance thatoperates with a flame, such as a furnace, water heater, or clothes dryer.Also avoid any area with a spark-producing electric motor, or wherepower tools are operated.

If possible, avoid storage areas with high humidity, because thatpromotes rust and corrosion.

Leave the fuel valve lever in the OFF position at the source to reducethe possibility of fuel leakage.

Remove the spark plug (see page 30).

Pour a tablespoon (5 10 cc) of clean engine oil into the cylinder.

Pull the starter rope several times to disribute the oil in the cylinder.

Reinstall the spark plug.

Pull the starter rope slowly until resistance is felt and the notch onthe starter pulley aligns with the hole at the top of the recoil startercover. This will close the valves so moisture cannot enter the enginecylinder. Return the starter rope gently.

Change the engine oil (see page 25).1.

2.

3.

4.

5.

1.


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35


Removal From Storage

With the engine and exhaust system cool, cover the engine to keep out

dust. A hot engine and exhaust system can ignite or melt somematerials. Do not use sheet plastic as a dust cover. A nonporous coverwill trap moisture around the engine, promoting rust and corrosion.

Position the equipment so the engine is level. Tilting can cause oilleakage.

Check your engine as described in the BEFORE OPERATIONchapter ofthis manual.

If the cylinder was coated with oil during storage preparation, theengine may smoke briefly at startup. This is normal.


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36


TRANSPORTING

If the engine has been running, allow it to cool for at least 15 minutesbefore loading the engine-powered equipment on the transport

vehicle. A hot engine and exhaust system can burn you and can ignitesome materials.

Keep the engine level when transporting to reduce the possibility offuel leakage. Turn the fuel valve OFF at the source.


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37

TAKING CARE OF UNEXPECTED PROBLEMS

ENGINE LACKS

POWER

Possible Cause Correction

ENGINE WILL NOT

START

Possible Cause Correction

Fuel valve OFF.

Choke OPEN.Engine switch OFF.

Out of fuel.

Spark plug faulty,

fouled, or improperly

gapped.

Spark plug wet with

fuel (flooded engine).

Carburetor malfunction,

ignition malfunction,

valves stuck, etc.

Check control

positions.

Check fuel.

Remove and inspect

spark plug.

Take engine to an

authorized Honda

servicing dealer, or

refer to shop manual.

Check air filter.

Take engine to an

authorized Honda

servicing dealer, or

refer to shop manual.

Filter element(s)

clogged.

Carburetor malfunction,

ignition malfunction,

valves stuck, etc.

Clean or replace filter

element(s) (p. 28).

Replace or repair faulty

components as

necessary.

OPEN valve.

Move lever to CLOSED.Turn engine switch to

ON.

Refuel.

Clean, gap, or replace

spark plug (p. 30).

Dry and reinstall spark

plug. Start engine with

throttle lever in FAST

position.

Replace or repair faulty

components as

necessary.

1.

2.

3.

4.

1.

2.


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38

TECHNICAL & CONSUMER INFORMATION

TECHNICAL INFORMATION

Serial Number Location

SERIAL NUMBER

& ENGINE TYPE

Engine serial number:

Record the engine serial number in the space below. You will need thisserial number when ordering parts, and when making technical orwarranty inquires (see page ).47


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39


Remote Control Linkage

RETURN SPRING

Flexible wire coremounting

Solid wire coremounting

WIRE

5 mmCIRCLIP

THROTTLELEVER

WIRE HOLDER

4 mm SCREW

OPTIONAL

WIRE HOLDER CHOKE LEVERREMOTE CHOKE LINKAGE

REMOTE THROTTLE LINKAGE

THROTTLE LEVERFRICTION NUT

The throttle and choke control levers are provided with holes foroptional cable attachment. The following illustrations show

installation examples for a solid wire cable and for a flexible, braidedwire cable. If using a flexible, braided wire cable, add a return springas shown.

It is necessary to loosen the throttle lever friction nut when operatingthe throttle with a remotely-mounted control.


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40


Carburetor Modification for High Altitude Operation

Fuel Regulator Information

The GX270 and GX390 LPG-fueled engine do not require anymodifications for high-altitude operation. However, performance will

decrease at high altitudes.

This engine is certified to comply with U.S. EPA and California ARBemission regulations using the Impco Beam regulator specified in theinstallation instructions (see below).Honda used this regulator and other specific parts and adjustments todemonstrate compliance with the emission regulations. Adjustablefuel system parts must have U.S. EPA and California ARB approvedtamper resistant features to limit the available adjustment after thefuel system is correctly installed.If an equipment manufacturer did not install your engine in a product,you will need the installation instructions for the Honda certifiedsystem (see below).If you choose not to use the Honda fuel system, you must use asystem that has been certified by the fuel system manufacturer to be

used on this Honda engine.Or, if you use a fuel system that is not already certified, you must havecertification test data satisfactory to the U.S. EPA or California ARB.The test data must prove the system will meet the emission standardboth when the engine is new and at the end of its emission durabilityperiod (hours).

To obtain a copy of the installation instructions for this engine, contactan independent Honda engine distributor, or our Customer Service

Department (page ).47


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41


Emission Control System Information

Source of Emissions

The U.S. and California Clean Air Acts

Tampering and Altering

The combustion process produces carbon monoxide, oxides ofnitrogen, and hydrocarbons. Control of hydrocarbons and oxides ofnitrogen is very important because, under certain conditions, theyreact to form photochemical smog when subjected to sunlight. Carbonmonoxide does not react in the same way, but it is toxic.

Honda utilizes lean carburetor settings and other systems to reducethe emissions of carbon monoxide, oxides of nitrogen andhydrocarbons.

EPA and California regulations require all manufacturers to furnishwritten instructions describing the operation and maintenance ofemission control systems.

The following instructions and procedures must be followed in order

to keep the emissions from your Honda engine within the emissionstandards.

Tampering with or altering the emission control system may increaseemissions beyond the legal limit. Among those acts that constitutetampering are:

Removal or alteration of any part of the intake, fuel or exhaustsystems.

Altering or defeating the governor linkage or speed-adjustingmechanism to cause the engine to operate outside its designparameters.


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42


Problems That May Affect Emissions

Maintenance

Replacement Parts

If you are aware of any of the following symptoms, have your engineinspected and repaired by your servicing dealer.

Hard starting or stalling after starting.

Rough idle.

Misfiring or backfiring under load.

Afterburning (backfiring).

Black exhaust smoke or high fuel consumption.

Follow the maintenance schedule on page . Remember that thisschedule is based on the assumption that your machine will be usedfor its designed purpose. Sustained high-load or high-temperatureoperation, or use in unusually wet or dusty conditions, will requiremore frequent service.

A manufacturer of an aftermarket part assumes the responsibility thatthe part will not adversely affect emission performance. Themanufacturer or rebuilder of the part must certify that use of the partwill not result in a failure of the engine to comply with emission

regulations.

The emission control systems on your Honda engine were designed,built, and certified to conform with EPA and California emissionregulations. We recommend the use of genuine Honda partswhenever you have maintenance done. These original-design

replacement parts are manufactured to the same standards as theoriginal parts, so you can be confident of their performance. The useof replacement parts that are not of the original design and qualitymay impair the effectiveness of your emission control system.

22


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43


Air Index

An Air Index Information hang tag/label is applied to engines certifiedto an emission durability time period in accordance with the

requirements of the California Air Resources Board.

The bar graph is intended to provide you, our customer, the ability tocompare the emissions performance of available engines. The lowerthe Air Index, the less pollution.

The durability description is intended to provide you with informationrelating to the engines emission durability period. The descriptiveterm indicates the useful-life period for the engines emission controlsystem. See your Emission Control Warranty for additionalinformation.

Extended

Intermediate

Moderate

Descriptive Term

300 hours (0 65 cc)500 hours (greater than 65 cc)



Applicable to Emissions Durability Period

The Air Index Information hang tag must remain on the engine until it

is sold. Remove the hang tag before operating the engine.


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44


Specifications

GX270

GX390

GX270/GX390 Tuneup

ITEM SPECIFICATION MAINTENANCE

50.7 lbs (23.0 kg)

4-stroke, overhead valve, single cylinder

16.5 cu-in (270 cm )

3.0 2.3 in (77 58 mm)

15.7 16.9 16.0 in(400 430 407 mm)

8.9 bhp (6.6 kW, 9.0 PS) at 3,600 rpm

Length Width Height

Dry weight

Engine type

Displacement

[Bore Stroke]

Max. output

Max. torque

Fuel consumption

Cooling system

Ignition system

PTO shaft rotation

14.1 lbfft (19.1 Nm, 1.95 kgfm) at 2,500 rpm

0.42 lb/hph (258 g/kWh, 190 g/PSh)

Forced air

Transistorized magneto

Counterclockwise

Length Width Height

Dry weightEngine type

Displacement

[Bore Stroke]

Max. output

Max. torque

Fuel consumption

Cooling system

Ignition system

PTO shaft rotation

16.7 17.7 17.4 in

(425 450 443 mm)

63.9 lbs (29.0 kg)

4-stroke, overhead valve, single cylinder

23.7 cu-in (389 cm )

3.5 2.5 in (88 64 mm)

12.9 bhp (9.6 kW, 13.0 PS) at 3,600 rpm

19.5 lbfft (26.5 Nm, 2.7 kgfm) at 2,500 rpm

0.42 lb/hph (258 g/kWh, 190 g/PSh)

Forced air

Transistorized magneto

Counterclockwise

Refer to page: 30

See your authorized

Honda dealer

Spark plug gap

Valve clearance

Other specifications

0.15 0.02 mm

0.20 0.02 mm

0.028 0.031 in

(0.70 0.80 mm)

]

][

[

No other adjustments needed.

(cold)

(cold)

IN:

EX:


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45


Wiring Diagram

Engine Types With Oil Alert


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46


CONSUMER INFORMATION

Honda Publications

Shop Manual

Parts Catalog

These publications will give you additional information formaintaining and repairing your engine. You may order them fromyour Honda engine dealer.

This manual covers complete maintenance and overhaul procedures.It is intended to be used by a skilled technician.

This manual provides complete, illustrated parts lists.


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47


Warranty Service Information

Servicing dealership personnel are trained professionals. They shouldbe able to answer any question you may have. If you encounter a

problem that your dealer does not solve to your satisfaction, pleasediscuss it with the dealerships management. The Service Manager orGeneral Manager can help. Almost all problems are solved in this way.

If you are dissatisfied with the decision made by the dealershipsmanagement, contact the Honda Power Equipment CustomerRelations Office. You can write to:

Or telephone: (770) 497-6400

When you write or call, please give us this information:

Name and address of dealer who services your engine

Name of dealer who sold the engine to you

Model and serial number (see page )

Date of purchase

Your name, address and telephone number

A detailed description of the problem

American Honda Motor Co., Inc.Power Equipment DivisionCustomer Relations Office4900 Marconi DriveAlpharetta, Georgia 30005-8847

38


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48

MEMO


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QUICKREFERENCE INFORMATION

LPG with a propane content of95 % or higher

Fuel

Engine Oil

Spark Plug

CarburetorMaintenance

SAE 30, API SJ, for general use

1.16 US qt (1.10 )BPR6ES

W20EPR-U0.028 0.031 in (0.70 0.80 mm)

Check engine oil level.Check air filter.Change engine oil.

Refer to the maintenanceschedule on page 22.

Type

Type

CapacityType

Gap

Idle speedBeforeeach useFirst 20hoursSubsequent

NGK:DENSO:

,

(page 23)

(page 30)1,400 rpm (page 31)

(page 26)

200150


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honda lpg (liquefied petroleum gas) engines

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