Northern Industrial Tools 998800 User manual

GAS-POWERED CUTOFF SAW
OWNER’S MANUAL
WARNING: Read carefully and understand all
INSTRUCTIONS before operating. Failure to follow the safety
rules and other basic safety precautions may result in serious
personal injury.
Item# 998800
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Thank you very much for choosing a NORTHERN TOOL + EQUIPMENT CO., INC. Product!
For future reference, please complete the owner’s record below:
Model: _______________ Purchase Date: _______________
Save the receipt, warranty and these instructions. It is important that you read the entire
manual to become familiar with this product before you begin using it.
This machine is designed for certain applications only. Northern Tool + Equipment
cannot be responsible for issues arising from modification. We strongly recommend this
machine is not modified and/or used for any application other than that for which it was
designed. If you have any questions relative to a particular application, DO NOT use the
machine until you have first contacted Northern Tool + Equipment to determine if it can or
should be performed on the product.
For technical questions please call 1-800-222-5381.
INTENDED USE
This Heavy-Duty Cutoff Saw cuts steel, stone, asphalt, concrete, rebar and more.
TECHNICAL SPECIFICATIONS & PACKING LIST
Item Specification
Engine Displacement (cc.) 71
Bore Diameter (in.) 2"
Stroke (in.) 1–13/32"
Idle Speed (RPM) 2700
Recommended Max. Speed, Unloaded (RPM) 9500
Power (watts) 3,400
Ignition Type BPMR-7A
Spark Plug (mm.)
0.5
Fuel Capacity (qt.) 0.73
Weight (without fuel and cutting blade) (lbs.) 22
Dimension (length ×width ×height) (in.) 26" x 11" x 20"
Cutting Blade Diamond Blade, Maximum 14"
Max. Operating Speed 5,400
Required Fuel Unleaded 90 Octane
Required Oil Two-Stroke Engine Oil
Engagement Speed (RPM) ≥3800
Rated Spindle Speed (RPM) ≤5400
Equivalent Sound Pressure Level at the Operator’s Position 102 dB(A)
Equivalent Sound Power Level from the Machine 114dB( A)
Vibration Level (hand/arm) Max. 12m/s2
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GENERAL SAFETY RULES
WARNING: The use of any cutoff machine can be dangerous. Because a cutoff
machine is a high-speed, fast-cutting power tool, special safety precautions must be
observed to reduce the risk of personal injury.
WARNING: Read and understand all instructions. Failure to follow all
instructions listed below may result in electric shock, fire and/or serious injury. Do not lend or
rent your cutoff saw without this manual.
WARNING: The warnings, cautions, and instructions discussed in this
instruction manual cannot cover all possible conditions or situations that could occur.
It must be understood by the operator that common sense and caution are factors which
cannot be built into this product, but must be supplied by the operator.
SAVE THESE INSTRUCTIONS.
WORK AREA
•Keep the work area clean, free of clutter and well lit. Cluttered and dark work areas
can cause accidents.
•Do not use your tool where there is a risk of causing a fire or an explosion; e.g.
in the presence of flammable liquids, gasses or dust. Power tools create sparks,
which may ignite the dust or fumes.
•Keep children and bystanders away while operating a power tool. Distractions can
cause you to lose control, so visitors should remain at a safe distance from the work
area.
•Be aware of all power lines, electrical circuits, water pipes and other mechanical
hazards in your work area, particularly those hazards below the work surface hidden
from the operator’s view that may be contacted unintentionally and may cause
personal harm or property damage.
•Be alert to your surroundings. Using power tools in confined work areas may put
you dangerously close to cutting tools and rotating parts.
INTERNAL COMBUSTION ENGINE SAFETY
WARNING: Only operate the engine in a well-ventilated area. Carbon Monoxide
produced by the engine during use can kill. Do not use indoors, near windows or in other
sheltered areas.
WARNING: Internal combustion engines present special hazards during
operation and fueling. Read and follow the warning instructions in the engine Owner’s
Manual and the safety guidelines below. Failure to follow the warnings and safety standards
could result in severe injury or death.
•DO NOT run the machine indoors or in an enclosed area such as a deep trench
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unless adequate ventilation, through such items as exhaust fans or hoses, is
provided. Exhaust gas from the engine contains poisonous carbon monoxide gas;
exposure to carbon monoxide can cause loss of consciousness and may lead to
death.
•DO NOT smoke while operating the machine.
•DO NOT smoke when refueling the engine.
•DO NOT refuel a hot or running engine.
•DO NOT refuel the engine near an open flame.
•DO NOT spill fuel when refueling the engine.
•DO NOT run the engine near open flames.
•DO NOT modify or disengage safety devices.
•DO NOT operate the machine if any safety devices or guards are missing or
inoperative.
•DO NOT touch the engine or muffler while the engine is on or immediately after it
has been turned off. These areas get hot and may cause burns.
•ALWAYS refill the fuel tank in a well-ventilated area.
•ALWAYS replace the fuel tank cap after refueling.
•ALWAYS check the fuel lines and the fuel tank for leaks and cracks before starting
the engine. Do not run the machine if fuel leaks are present or the fuel lines are
loose.
•ALWAYS avoid contact with hot fuel, oil, exhaust fumes and solid surfaces.
•ALWAYS be sure that the operator is familiar with proper safety precautions and
operation techniques before using the machine.
•ALWAYS close the fuel valve when the machine is not being operated.
•ALWAYS operate the machine with all safety devices and guards in place and in
working order.
•ALWAYS avoid conditions that can create “kick-back”.
NOTE: All Federal and State laws and any regulation having jurisdiction covering the safety
requirements for use of the machine take precedence over the statements in this manual.
Users of this machine must adhere to such regulations.
PERSONAL SAFETY
•Stay alert. Watch what you are doing and use common sense when operating a
power tool. Do not use a power tool while you are tired or under the influence of
drugs, alcohol or medication. A moment of inattentiveness while operating power
tools may result in serious personal injury.
•Dress properly. Do not wear loose clothing, dangling objects, or jewelry. Keep
your hair, clothing and gloves away from moving parts. Loose clothes, jewelry
and/or long hair can be caught in moving parts. Air vents often cover moving parts
and should be avoided.
•Use the proper safety apparel and equipment. Use safety goggles or safety
glasses with side shields which comply with current national standards, or when
needed, a face shield. Use as dust mask in dusty work conditions. This applies to
all persons in the work area. Also use non-skid safety shoes, a hardhat, gloves, a
dust collection system and hearing protection when appropriate.
•Avoid accidental starting. Do not carry the power tool with your finger on the
switch. Ensure the switch is in the off position before starting.
•Do not overreach. Keep your footing and balance at all times.
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•Remove adjusting keys or wrenches before connecting the tool to the power
supply or turning it on. A wrench or key that is left attached to a rotating part of the
tool may result in personal injury.
TOOL USE AND CARE
•Do not force the tool. Tools do a better and safer job when used in the manner for
which they are designed. Plan your work, and use the correct tool for the job.
•Never use a tool with a malfunctioning on/off switch. Any power tool that cannot
be controlled with the switch is dangerous and must be repaired by an authorized
service professional before using.
•Disconnect spark plug from the tool and place the switch in the locked or off
position before servicing, adjusting, installing accessories or attachments or storing.
Such preventative safety measures reduce the risk of starting the power tool
accidentally.
•Secure your work with clamps or a vise instead of your hands when practical.
This safety precaution allows for proper tool operation using both hands.
•Use both hands to operate the saw.
•Always stop the engine and let the wheel come to a complete stop before putting
down or carrying the saw.
•This saw vibrates during use. Repeated or long-term exposure to vibration may
cause temporary or permanent physical injury, particularly to the hands, arms and
shoulders. Vary your time of operation.
•Make sure the Cutting Wheel's maximum operating speed is greater than the
maximum motor speed of 9500 RPM.
•Inspect the abrasive wheel frequently and replace immediately if cracked,
warped or showing other signs of wear.
•Never use circular saw blades,carbide-tipped blades, rescue blades, wood cutting
blades or toothed blades with this saw.
•Store idle tools. When tools are not is use, store them in a dry, secure place out
of the reach of children. Inspect the tools for good working condition prior to
storage and before re-use.
•Use only manufacturer-recommended accessories for your model. Accessories
that may be suitable for one tool may cause injury when used on another tool.
•Do not store the Cut-off Saw with the Blade installed.
•Keep all guards in place and in working order.
•Never leave the tool unattended when running.
DIAGRAM AND PARTS LIST
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1. Operator's Manual
2. Decompression Valve
3. Water Valve
4. Adjustment Handle for Blade Guard
5. Blade Guard
6. Throttle Control
7. Fuel Tank
8. Cutting Arm
9. Belt Tensioning Screw
10. Cutting Arm
11. Cutting Blade
12. Front Handle
13. Air Filter Cover
14. Chock
15. Stop Switch
16. Throttle Trigger Locknut
17. Starter
18. Starter Handle
19. Cylinder Cover
20. Starter Throttle Catch
ASSEMBLY
Check the Drive Shaft and Flanges
•Check the Drive Shaft for damage.
•Check the contact surfaces of the Cutting Blades and the Flanges. Make sure they
are flat, run correctly on the spindle and are free from foreign objects.
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•Do not use Flanges that are twisted, have damaged edges, are dirty or are a different
size than specified for the tool.
Fitting the Cutting Blade
The Blade is placed between the inner Flange Hub (A) and the outer Flange Hub (B). The
Flange Hub is turned so that it fits on the Axle. The Shaft can be locked using a screwdriver,
steel pin or similar tool. The Blade is tightened clockwise. Tightening torque for the bolt
holding the Blade is 15–25 Nm (11–18 ft./lbs.).
Blade Guard
Check the Blade Guard for cracks or other damage. Clean the inside of the guard before
installing a new wheel. Check that the guard can be adjusted and locked.
WARNING: The Blade Guard must be correctly installed prior to starting the
machine.
The Blade Guard should always be fitted on the Power Cutter.
The guard should be adjusted so that the rear section is close to the work piece. The best
distance is 1/4–9/32in. (6.5–7mm). The guard will collect cutting fragments and sparks,
keeping them away from the user.
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OPERATION
WARNING! Carbon monoxide in exhaust fumes can cause serious injury or death;
ensure proper ventilation before using this tool.
CUTTING
Check that no one is in the immediate vicinity when starting the machine or while working
with the machine to avoid distractions and control of the Power Cutter. This cutoff saw is a
one-person tool.
Avoid using the tool in unfavorable weather conditions.
Ensure that the work area is clear and that you have a firm foothold before operating this
tool. Be aware of potential obstacles and ensure that when cutting, no material can become
loose and fall, as this could cause injuries.
Take great care when working on uneven surfaces.
Make sure clothing and parts of the body do not come into contact with the Cutting Blade
when the engine is started.
Maintain a safe distance from the Cutting Blade when the engine is running.
The Blade Guard should always be fitted when the engine is running.
Ensure that the work area is sufficiently illuminated to create a safe working environment.
Do not move the Power Cutter when the Blade is rotating.
Some working positions may create greater stress on the operator.
Make sure that no pipes or electrical cables are routed in the area to be cut.
Cutting Technique
The technique described below is a general guideline. Check the
specific information for each Blade regarding individual cutting
characteristics (for example, a Diamond Blade requires less feeding
pressure than an Abrasive Disc).
1. Ensure that the work piece is fully supported to prevent
unpredictable movement.
2. Always cut with the throttle at full.
3. Do not force or squeeze the Blade into position.
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4. Use the appropriate Blade speed.
5. Move the Blade slowly backwards and forwards.
6. Only use the Blade's cutting edge when cutting.
7. Ensure that Blade is fully vertical while cutting; cut at right angles to the work piece.
WARNING!
•NEVER cut using the side of the Blade; doing so can cause damage and
serious injury.
•ALWAYS protect the wheel from hitting the ground or other objects that
may cause damage to the wheel.
•NEVER pull the Power Cutter to one side; doing so will cause the Blade to
jam or break and could result in serious injury.
Water Cooling
Water cooling is used with gas-powered cutters when cutting concrete. The water cools the
Blade, increases service life and reduces dust. Among the disadvantages are difficulties at
very low temperatures, the risk of damaging the floor and other sections of the building and
the risk of slipping.
Diamond Blades
Diamond Blades become dull and lose their effectiveness if used with the wrong feeding
pressure or when cutting materials such as heavily reinforced concrete. Working with a dull
Blade can cause overheating and potential damage.
Abrasive Discs
Do not use water with Metal Abrasive Discs. Discs can become uneven and cause damage
or potential injury if they come in contact with water or are stored in moist conditions.
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Blade Vibration
Take care in selecting feeding pressure; excessive feeding pressure can cause a Blade to
vibrate and lose proper shape.
Choosing a lower feeding pressure will usually stop vibrations; if vibration continues, replace
the Blade.
How to Avoid kickback
WARNING: Kickback can occur very suddenly and with great force. Follow the
directions below to minimize the risk of serious injury or even death.
1. Never cut with the top segment (illustrated in the diagram below).
2. Keep your balance and a firm foothold.
3. Use both hands and take a firm grip with the thumb and fingers around the
handle.
4. Stand at a comfortable distance from the work piece.
5. Run the Power Cutter at full throttle.
6. Take care when inserting the Blade in an existing cut.
7. Never cut above shoulder height.
8. Be alert to the movement of the work piece or anything else that can occur,
which could cause the cut to close and pinch the Blade.
WARNING: Sparks from cutting metal can burn or cause clothing to catch fire.
Wear appropriate clothing and keep fire extinguishing equipment readily available.
Pull In/Pinching
Pull In occurs when the lower part of the Blade is suddenly stopped or when the cut closes.
Pinching occurs when the cut closes around the Blade. When this happens, the Cutter can
be pulled down suddenly with great force and can cause injury.
To avoid Pull In/Pinching, ensure that the work piece is supported in a way that keeps the cut
open and the pieces in place until cutting is complete.
Check the Speed of the Drive Shaft
Use a tachometer (not included) regularly to check the speed of the Drive Axle at full throttle
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and without a load. The maximum speed is stated on the machine.
WARNING! If the Drive Axle speed is higher than the stated maximum speed, the
machine should be adjusted by an authorized service professional before it is used.
Care and Storage of the Power Cutter
Always handle the Power Cutter carefully and store it with the Blade removed.
Handling the Cutting Blades
•Blades should always be removed from Cutter following use and should be stored
carefully in dry conditions.
•Abrasive Discs require special handling. They must be stored on a flat, level
surface. Spacers should be used if Blades are supplied with a Backing Pad.
•Inspect all Blades for damage prior to use.
If used improperly, Cutting Blades may burst and cause injury.
•Never use a Cutting Blade at a lower speed than is specified.
•Never use a Cutting Blade for any other purpose than specified.
Cutting Blade Design
Cutting Blades come in two standard designs: Abrasive Discs and Diamond Blades.
Northern Industrial Cutting Discs are designed specifically for High Speed Power Cutters. If
you choose to use Blades from other sources, ensure that the Blades fit the specifications for
this Saw and comply with local regulations.
Abrasive Discs
Abrasive Discs use grit bonded to the Disc as cutting material. Reinforced Blades include a
fabric- or fiber-base that prevents total breakage at maximum working speed if the Blade
becomes cracked or damaged. The performance of an Abrasive Cutting Blade is determined
by the type of abrasive used and the type and hardness of the bonding agent.
Soft and Hard Blades
Blades that have a greater cutting capacity but a shorter service life are called Soft Blades.
Blades with a longer service life but slower cutting capacity are called Hard Blades. The
chart below provides additional information about Abrasive Blade characteristics.
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ABRASIVE DISCS TYPES AND USES USE
Blade
Type General
Characteristics Recommended Materials Water Cooling Applications
Concrete
Universal
application
Economical
Concrete, asphalt,
stone, brickwork,
cast iron, aluminum,
copper, brass,
cables, rubber
Can be used to
reduce dust. The
disc should not be
stored after cutting
is complete as water
affects the strength
of the disc while
stored. (Note: The
rusted Diamond
Blade may cause
serious injury.)
Metal Designed for
metalwork only Steel, steel alloys and other hard
metals NOT recommended
Examining Blades Before Use
Ensure that the Blades have been packaged or stored safely before use.
You can test an Abrasive Disc by hitting it lightly with a piece of wood. If the Blade does not
give a full-sounding ring, it is damaged and should not be used.
Never use a Blade that has fallen to the floor.
Specifications for Fitting Blades
Use the chart below to ensure your Blade fits properly.
Specifications for Fitting Abrasive Cutting Blades
Standard Spindle Size 1in. (25.4mm) / 3/4in. (20mm)
Min. Thickness of the Blade 1/8in. (3mm)
Spindle Hole/Drive Shaft Clearance .05in. (0.2mm)
Flange Tightening The bolt is tightened to 15–25Nm
Blade/Guard Check that the Blade runs free of the Guard.
Diamond Blades
Diamond Blades feature a steel body with segments that contain industrial diamonds. Refer
to the chart below for applications where Diamond Blades are indicated.
Diamond Blade Characteristics
Diamond Advantages Material Water cooling
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Blade Lower cost per
cutting operation.
Requires fewer
Blade changes.
Produces less dust
than Abrasive Discs.
All brickwork, reinforced
concrete and other composite
material.
Never use the Cutoff Saw with
saw blades, cutter blades,
brushes, carbide tipped, wood
cutting blades etc.
Water cooling is highly
recommended and
increases the Blade
service life.
We highly recommend that users cool Diamond Blades continuously with water to prevent
overheating that can cause Blade failure and potential injury and damage.
Proper Use of Diamond Blades
•Ensure that the Cutting Blade rotates in same direction as the markings indicate.
•Continually cool the Blade with water.
•Keep the Blade sharp.
•Always remove the Cutting Blade during transport.
•Never run a Blade in the opposite direction of the indicated markings.
•Never force a dull Blade or wedge a Blade into a cut.
•Never let the Blade fall onto a work piece.
Dry Cutting Diamond Blades
Dry Cutting Diamond Blades are a new generation of Blades. While these Blades do not
require water cooling, they can still be damaged by excessive heat. When using these
Blades, we recommend that the user let the Blade cool by lifting the Blade from the cut every
30-60 seconds, allowing the Blade to rotate in the air for 10 seconds to cool, then resuming
work.
Starting Your Cutoff Saw
Before starting, observe the following:
•Ensure the Cutting Arm, Belt and Cutting Head are in position; if they are not, the
clutch can disengage and cause injury.
•Ensure you have firm footing.
•Ensure that the Cutting Blade rotates freely.
•Keep unauthorized individuals away from the work area.
Starting a Cold Engine
1. Slide the Stop Switch to the Run position.
2. Press down the Choke Lever.
Press in the Throttle Control and thereafter the Starter Throttle Catch (Release the Throttle
Control) and the Throttle is blocked in Half Throttle position. The Catch is released when the
Throttle Control is pressed all the way in.
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3. Press in the Valve (B) to reduce the pressure in the Cylinder. This assists starting the
Cutter. Always use the Decompression Valve when starting the machine. When the
machine starts, the Valve automatically returns to its original position.
4. Hold the Front Handle with your left hand. Place your right foot on the lower section of
the Rear Handle, pressing the Cutter against the ground.
5. Grip the Starter with your right hand and slowly pull the Starter Cord until you feel
resistance, then pull the Cord quickly. Be careful to avoid pulling the Starter Cord
completely and avoid releasing the Starter from the fully extended position. Doing so
can damage the machine.
6. Press the Choke Control immediately when the engine fires. When the engine starts,
quickly apply full throttle; this will cause the Starter Throttle Catch to disengage
automatically.
Starting a Warm Engine
Use the same procedure for starting a cold engine but without the choke.
WARNING! The Cutting Blade can rotate when the engine starts. Make
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sure it can rotate freely before starting the engine. To stop the engine, turn off the
ignition by pressing the Switch to the Stop position.
FUEL HANDLING
Fuel Mix
This Cutoff Saw is equipped with a two-stroke engine and requires a mixture of gasoline and
two-stroke engine oil. It is important to measure the amount of oil accurately to ensure the
proper gasoline/oil ratio. When mixing small amounts of fuel, even a small inaccuracy can
drastically affect the ratio of the mixture and affect engine performance.
WARNING!
•Always provide proper ventilation when handling fuel.
•Use good quality gasoline with an octane of 90 or greater. Lower octane gasoline
can cause knocking which can result in damage to the engine.
•Use good quality 2-stroke engine oil that is designed for air-cooled engines.
•Follow a 1:25 oil/gasoline mixing ratio.
•Never use oil intended for 4-stroke engines.
•Mix oil and gasoline in a clean container intended for fuel.
•To mix the product, first place half the gasoline you are using into the container.
•Next, add the entire amount of oil.
•Mix the fuel mixture by shaking it gently in the container.
•Finally, add the remaining gasoline and mix again.
•Do not mix more than one month's supply of fuel at a time.
•Empty the fuel tank if the cutter will not be used for an extended period.
Adding Fuel
•Never smoke or place any sources of heat near the fuel.
•Always move the Cutoff Saw at 10ft. from the fueling area before starting.
•Check for fuel leakage during refueling and operation. If leakage is found, do not
start the engine until the issue has been corrected by a qualified technician.
•Never refuel when the engine is running.
•When adding fuel, open the cap slowly to ensure that pressure is released slowly.
•Carefully tighten the cap after adding fuel.
•Keep the Handle dry, clean and free from fuel and oil.
•Clean any fuel residue from the area around the fuel cap.
•Keep the fuel tank clean; all fuel should be changed at least once a year.
•Keep the fuel tank free of contaminants.
Speed Adjustment
If you need to adjust idling speed, follow these instructions:
•Turn the screw clockwise until Cutting Disc begins to rotate, then turn
counterclockwise until Disc stops rotating.
•Idling speed is correctly adjusted when engine speed (approximately 2,700 RPM) is
stable in all working positions.
•Idling speed should not exceed 2,900 RPM.
•The difference between idling speed and the speed in which the blade rotates should
be at least 1,000 RPM.
•The Cutter includes a built-in governor which limits engine speed to 9500 RPM;
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maximum spindle speed is 5400 RPM.
•If the maximum spindle speed exceeds 5400 RPM, stop using the Cutter and have it
repaired by an authorized service professional.
ADJUSTING THE DRIVE BELT
The Drive Belt is enclosed and protected from dust, dirt and mechanical damage when the
tool is operating. To adjust the Belt:
1. Loosen the two bolts (A).
2. Turn the tensioning screw (B) so that the nut (C) is located directly under the arrow
on the cover.
3. Shake the Head to ensure the spring is in position to tension the Belt; the Belt now
has the correct tension.
4. Tighten the two bolts (A).
CHANGING THE DRIVE BELT
To change the drive belt, follow these instructions:
1. Tighten the two bolts (A).
2. Turn the tensioning screw (B) until the tension has been released.
3. Remove the two bolts (A).
4. Remove the Front Belt Cover (E).
5. Remove the Belt from the Pulley.
6. Remove the Cutting Head.
7. Loosen the bolt (D) and remove the Back Belt Cover (F).
8. Replace the Drive Belt.
9. Replace the Back Belt Cover (F) and tighten the bolt (D).
10. Replace the Cutting Head.
11. Replace the Front Belt Cover (E).
12. Replace the two bolts (A).
13. Tighten the tensioning screw (B).
14. Tighten the two bolts (A).
NOTE: A new Drive Belt should be tensioned after using 1-2 tanks of fuel.
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WARNING! NEVER use the Power Cutter without the Blade Guard in
position over the Cutting Blade.
WARNING! NEVER start the engine when the Pulley and Clutch are
removed.
Carburetor
The engine on your unit will be broken in after you have run 8-10 tanks of fuel. To ensure
peak performance after the break-in period, have your carburetor checked at an authorized
service center, which has a revolution counter available.
The carburetor governs engine speed via the throttle; air and fuel are mixed in the carburetor.
Your engine's carburetor is equipped with fixed jets to ensure the engine receives the correct
fuel/air mixture. If the engine lacks power or accelerates poorly, inspect and replace the air
filter if necessary. If this does not help, contact an authorized service center.
Final Setting of the Idling Speed
To start the engine first, find the Low Speed Adjusting Screw illustrated in the below. Use a
screw driver to turn the screw clockwise to speed up. Turn the screw counterclockwise to
reduce speed.
A correctly adjusted idle speed setting occurs when the engine run smoothly in every
position. Idling speed should be in a certain range. Recommended idling speed: 2,700 RPM.
WARNING! The Blade should stop while at idling speed. If the Blade does
not stop at idle speed and cannot be adjusted, do not use the machine until it has
been serviced.
Fuel Filter
The fuel filter sits inside the fuel tank. Keep contaminants out of the tank to avoid damaging
the fuel filter. The filter cannot be cleaned and must be replaced if damaged. The filter should
be changed at least once a year.
Air Filter
The air filter should be cleaned regularly, removing dust and dirt to avoid:
•Carburetor malfunction
•Starting problems
•Reduced engine power
•Unnecessary wear to engine parts
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The air filter system consists of a main filter and a back-up filter:
The main filter is an oiled foam rubber filter that is easily accessible. This filter should be
inspected after every other fueling. To ensure effectiveness, the filter must be inspected and
cleaned regularly.
Cleaning the Filter
Wash the filter carefully in warm, soapy water. After cleaning, rinse the filter thoroughly in
clean water. Then squeeze out the filter and let it dry. Do not use compressed air to dry the
filter because it can damage the foam.
Oil the filter carefully. It is extremely important that the entire filter is saturated in oil.
•The foam rubber filter will wear after repeated washing. Replace with a new filter if it
is no longer elastic and does not seal well against the filter cover.
•The backup filter is a paper filter and is found under the cover. This filter should be
cleaned when the engine’s power drops. Clean the filter by shaking or carefully using
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compressed air. DO NOT WASH THE FILTER.
•Ensure that the main filter is installed in the proper position; the bottom characters on
the main filter should face the handle of the unit.
Water Filter
Check and clean the water filter as needed.
STARTER
WARNING: The Recoil Spring sits in its tensioned position in the Starter Housing
and can fly out and cause injury if handled carelessly. Use care and wear protective glasses
when replacing the Recoil Spring or the Starter Cord.
To replace a broken or worn Starter Cord, do the following:
•Loosen the Filter Cover and Cylinder Cover.
•Loosen the bolts that hold the Starter against the Crankcase and lift off the Starter
Unit.
•Pull the Cord out approximately 12" and lift it out of the cut-out in the Starter Pulley's
periphery. Reset the Recoil Spring by allowing the Pulley to slowly rotate backwards.
•Loosen the screw in the center of the Starter Pulley and lift off the Pulley.
•Wind the Cord on the Pulley.
•Fit the Pulley on the Recoil Spring so the end of the Recoil Spring Hooks on the
Pulley.
•Fit the screw in the center of the Pulley.
•Thread the Starter Cord through the hole in the Starter Housing and the Starter
Handle.
•Tie a good knot on the end of the Cord.
Tensioning the Recoil Spring
To tension the Recoil Spring, lift the Starter Cord from the cutout on the Pulley and turn the
Pulley clockwise approximately 2 revolutions.
NOTE: Ensure that the Starter Pulley can be turned at least 1/2 additional revolution when
the Starter Cord is fully extended.
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Replacing a Broken Recoil Spring
•Lift the Starter Pulley (see "Changing a broken or worn Starter Cord").
•Loosen the screws holding the Spring Cassette.
•Disassemble the Recoil Spring by tapping the Pulley lightly against a work bench or
similar object.
•Lubricate the Recoil Spring with thin oil.
•If the Spring pops out during assembly, remount it, out and then in, toward the
center.
•Reassemble the Starter Pulley and tension the Recoil Spring.
Installing the Starter
To install the Starter, first pull out the Starter Cord, then place the Starter in position on the
Crankcase. Slowly release the Starter Cord so that the pawls grip the Pulley. Tighten the
screws that hold the Starter in place.
MAINTENANCE
• Maintain your tools. It is recommended that the general condition of any tool be examined
before it is used. Keep your tools in good repair by adopting a program of conscientious
repair and maintenance in accordance with the recommended procedures found in this
manual. If any abnormal vibrations or noise occurs, turn the tool off immediately and have
the problem corrected before further use. Have necessary repairs made by qualified service
personnel.
• Keep the cutting tools sharp and clean. Properly maintained cutting tools with sharp
cutting edges are less likely to bind and are easier to control. Keep handles dry, clean, and
free from oil and grease.
• Cleaning. Use only soap and a damp cloth to clean your tools. Many household cleaners
are harmful to tool housing and insulation. Never let liquid get inside a tool.
Spark Plugs
Deposits can form on Spark Plugs that may cause abnormal wear and tear. Monitoring your
carburetor setting and using the correct fuel mixture can prevent premature wear on Spark
Plugs.
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