mcculloch MB2500BP USER MANUAL
USER MANUAL
Gas Backpack Blower
Model : MB2500BP
SAFETY • OPERATION • MAINTENANCE
WARNING • PLEASE READ
For your own safety please read this manual before attempting to operate your new unit. Failure to follow instructions can result in serious personal injury. Spend a few moments to familiarize yourself with
your blower before each use.
PN 9096-MD1805 Printed in Taiwan
INTRODUCTION 1 - GENERAL INFORMATION
PLEASE READ
The WARRANTY SYMBOL indicates that unless
instructions or procedures are followed any damage
caused will void the warranty and repairs will be at owner’s
expense. A CAUTION may also accompany the WARRAN-
TY SYMBOL.
Service other than user maintenance should be performed
by a McCulloch Authorized Service Center. Damage or
conditions which render this product inoperable caused by
improper maintenance practices will void the manufacturer’s warranty.
FOR WARRANTY OR SERVICE CONTACT THE NEAR-
EST McCULLOCH AUTHORIZED SERVICE CENTER
LISTED UNDER “SAWS” IN YOUR TELEPHONE
DIRECTORY YELLOW PAGES.
TABLE OF CONTENTS
1 GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . .2
1-1. Specifications
2 GENERAL IDENTIFICATION . . . . . . . . . . . . . . . . . . . . . . . . .3
2-1. General Identification
3 SAFETY PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
3-1. What To Do
3-2. What No To Do
3-3. International Symbols
4 ASSEMBLY INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . .6
4-1. Attach Flex Tube
4-2. Attach Operating Tube
4-3. Attach Intermediate Tube and Concentrator Nozzle
4-4. Adjust Back Pack Harness and Control Handle
5 FUEL AND LUBRICATION . . . . . . . . . . . . . . . . . . . . . . . . . .7
5-1. Fuel
5-2. Mixing Fuel
5-3. Fuel Mixing Table
5-4. Recommended Fuels
5-5. Fuel and Lubrication Symbols
6 STARTNG/STOPPING INSTRUCTIONS . . . . . . . . . . . . . . . .8
6-1. Starting a Cold Engine
6-2. Important Idling Information
6-3. Stopping The Engine
6-4. Starting a Warm Engine
7 OPERATING INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . .10
7-1. Blower Operations
7-2. Operation Instructions
8 MAINTENANCE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . .11
8-1. Maintenance Schedule
8-2. Air Filter
8-3. Fuel Cap / Fuel Filter
8-4. Idle Adjustment
8-5. Spark Plug
8-6. Storage
8-7. Removing a Unit From Storage
9 TROUBLESHOOTING THE ENGINE . . . . . . . . . . . . . . . . .15
10 PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
1
1-1. SPECIFICATIONS
ENGINE
Engine Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air-cooled, 2 Cycle,
Displacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25cc (2.0ci)
Idle Speed RPM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,800 - 4,000rpm
Operating RPM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7,800+ rpm
Ignition Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electronic
Ignition Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rocker Switch
Spark Plug Gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.024 in. (0.6 mm)
Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel/Oil Mixture
Fuel/Oil Ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40:1
Carburetor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . with primer
Starter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Smooth PullTMStarting system
Muffler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Baffled with Guard
Fuel Tank Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17.58 oz. (520 ml.)
BLOWER
Throttle Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Finger-Tip Trigger
Blower Velocity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . up to 170 mph
Blower Air Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . up to 485 cfm
Approximate Unit Weight (No fuel) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.9 lb.
Use goggles and hearing protection
2
2 - GENERAL IDENTIFICATION
22
4
19
21
20
23
17
3
2
5
7
1
11
8
9
10
12
24
13
6
24
18
2-1. GENERAL IDENTIFICATION
1. THROTTLE TRIGGER
2. THROTTLE LOCK
3. ON/OFF IGNITION SWITCH
4. TOP ASSIST HANDLE
5. SPARK PLUG WIRE / SPARK PLUG
6. CHOKE LEVER
7. STARTER HANDLE
8. AIR CLEANER COVER
9. FUEL CAP
10. FUEL TANK
11. PRIMER BULB
12. HARNESS
13. CONTROL HANDLE
14. OPERATING TUBE
3
15
14
15
16
15. HOSE CLAMP
16. FLEX TUBE
17. THROTTLE LINKAGE
18. MUFFLER COVER
19. SPARK ARRESTER SCREEN
20. VENTED BACK PAD
21. INTERMEDIATE TUBE
22. 56mm NOZZLE
23. 40mm CONCENTRATOR NOZZLE
24. THROTTLE LINKAGE CLIPS
3 - SAFETY PRECAUTIONS
3-1. WHAT TO DO
READ YOUR USER MANUAL AND ALL SUPPLEMENTS
(IF ANY ENCLOSED) THOROUGHLY BEFORE OPERATING YOUR UNIT.
1. WEAR CLOSE FITTING, TOUGH WORK CLOTHING
that will provide protection, such as long slacks or
trousers, safety work shoes, heavy duty work gloves,
hard hat, a safety face shield, or safety glasses for eye
protection and a good grade of ear plugs or other
sound barriers for hearing protection.
2. REFUEL IN A SAFE PLACE. Open fuel cap slowly to
release any pressure which may have formed in fuel
tank. Always wipe unit of fuel or oil spills before starting. To prevent a fire hazard, move at least 10 feet (3
meters) from fueling area before starting.
3. COMPLY WITH ALL FIRE PREVENTION REGULATIONS. COMPLIANCE WITH ALL LOCAL, STATE, OR
FEDERAL LAWS IN THE UNITED STATES IS THE
USER’S RESPONSIBILITY. Your unit comes with a
spark arrester screen furnished in the user kit.
Replacement spark arrester screen kits are available
at your nearest McCulloch Authorized Service Center
listed under “SAWS” in your Telephone Directory
Yellow Pages.
4. TURN UNIT OFF before setting it down, and also
before installing or removing attachments.
5. KEEP ALL SCREWS AND FASTENERS TIGHT and
the unit in good operating condition. Never operate this
equipment if it is improperly adjusted or not completely and securely assembled.
6. KEEP HANDLES DRY, clean and free of fuel mixture.
7. STORE EQUIPMENT AWAY FROM POSSIBLE IGNITION SOURCES, such as gas-powered water heaters,
clothes dryers, or oil-fired furnaces, portable heaters,
etc.
8. ALWAYS KEEP the engine free of debris build-up.
9. OPERATION OF EQUIPMENT should always be
restricted to mature and properly instructed individuals.
10. ALL PERSONS WITH RESPIRATORY PROBLEMS
and persons operating blower in very dusty environments, should wear a dust particle mask at all times.
Paper dust masks are available at most paint and
hardware stores.
3-2. WHAT NOT TO DO
1. DO NOT USE ANY OTHER FUEL than that recommended in your manual. Always follow
instructions in the Fuel and Lubrication section of this
manual. Never use gasoline unless it is properly
mixed with 2-cycle engine lubricant. Permanent damage to engine will result, voiding manufacturer’s warranty.
2. DO NOT SMOKE while refueling or operating equip-
ment.
3. DO NOT OPERATE UNIT WITHOUT A MUFFLER and
properly installed muffler shield.
4. DO NOT TOUCH or let your hands or body come in
contact with a hot muffler or spark plug wire.
5. DUE TO THE DANGER of exhaust fumes, never oper-
ate blower in a confined or poorly ventilated area.
6. NEVER POINT BLOWER in the direction of people,
animals, buildings, automobiles, or windows, etc.
7. DO NOT operate unit without inlet cover installed to
prevent contact with impeller.
8. DO NOT set a hot engine down where flammable
material is present.
9. DO NOT OPERATE UNIT FOR PROLONGED PERI-
ODS. Rest periodically.
10. DO NOT OPERATE UNIT WHILE UNDER THE
INFLUENCE OF ALCOHOL OR DRUGS.
11. DO NOT ADD, REMOVE OR ALTER ANY COM-
PONENTS OF THIS PRODUCT. Doing so could
cause personal injury and/or damage the unit voiding
the manufacturer’s warranty.
12. DO NOT operate your unit near or around flammable
liquids or gases whether in or out of doors. An explosion and/or fire may result.
13. DO NOT WEAR loose clothing, scarfs, neck chains,
unconfined long hair, and the like. Doing so could
cause injury associated with objects being drawn into
the rotating parts.
14. DO NOT refuel a running engine or an engine that is
hot.
4
Minimum
50Ft.
3-3. INTERNATIONAL SYMBOLS
1
2
3
Minimum operating distance
3 - SAFETY PRECAUTIONS
Use of these personal safety items is highly recommended to
reduce the risk of accidental injury.
Read the User Manual.
FULL Choke Position
Pump the primer bulb 10 times.
PARTIAL Choke Position
RUN Choke Position
5
4 - ASSEMBLY INSTRUCTIONS
4-1. ATTACH FLEX TUBE
Put the hose clamp(C) on the flex tube before connecting
the flex tube and the fan’s outlet tube together.
Connect the flex tube (B) to the fan’s outlet tube (A) (Fig.
4-1A) with a hose clamp (C) (Fig. 4-1B) and tighten
securely (Fig. 4-1B).
B
D
F
180˚
4-2A
B
A
4-1A
4-2B
THROTTLE LINKAGE CLIPS
C
G
E
4-1B
4-2. ATTACH OPERATING TUBE
NOTE: keep the throttle cable as straight as possible when
connecting the blower tubes.
1. Place the unit on flat surface during assembly. Insure
screw mechanism of clamp is positioned away from
operator.
2. Put the hose clamp (C) on the flex tube and the operating tube before connecting them together.
3. Turn the throttle linkage mark (D) so it aligns with the
throttle handle (F) (Fig.4-2A). Insert the operating
tube (E) into the flex tube (B) (Fig. 4-2A) and then
tighten securely with a hose clamp (G) (Fig. 4-2B).
4. Attached throttle linkage clips (# 24-know your blower)
- to both ends of the flex tube to secure the throttle
cable. ( Fig. 4-2D)
4-2C
THROTTLE LINKAGE CLIPS
4-2D
6
4 - ASSEMBLY INSTRUCTIONS
4-3. ATTACH INTERMEDIATE TUBE AND
CONCENTRATOR NOZZLE
Connect the intermediate tube (H) and concentrator nozzle (I) or 56mm nozzle (J) (you can only use I nozzle at
time). Push the tubes together and turn them clockwise
so that they lock together (Fig. 4-3A). Use concentrator
nozzle when you need more airflow in tight places: flower
beds, under decks, etc.
B
D
H
J
4-3A
I
40mm
56mm
5 - FUEL AND LUBRICATION
4-4. ADJUST BACK PACK HARNESS AND
CONTROL HANDLE
1. Place blower on your back by slipping arms through
the shoulder straps as if you were putting on a jacket
(Figure 4-4A).
2. Adjust backpack harness and control handle.
3. Once adjustments have been made, to the straps for
user comfort, remove the blower from your back and
place on level ground in an upright position.
4-4A
5-1. FUEL
Use regular grade unleaded gasoline mixed with Genuine
Factory Parts 40:1 custom 2-cycle engine oil for best
results. Use mixing ratios in Section 5-3.
Never use straight gasoline in your unit. This will
cause permanent engine damage and void the manufacturer’s warranty for that product. Never use a fuel mixture that has been stored for over 90 days.
If 2-cycle lubricant other than Genuine Factory Parts
Custom Lubricant is to be used, it must be a premium
grade oil for 2-cycle air cooled engines mixed at a 40:1
ratio. Do not use any 2-cycle oil product with a recommended mixing ratio of 100:1. If insufficient lubrication is
the cause of engine damage, it voids the manufacturer’s
engine warranty.
5-2. MIXING FUEL
Add oil to an approved fuel container followed by the gasoline to allow incoming gasoline to mix with oil. Shake container to ensure thorough mix.
Lack of lubrication voids engine warranty. Gasoline
and oil must be mixed at 40:1.
5-3. FUEL MIXING TABLE
5-4. RECOMMENDED FUELS
Some conventional gasolines are being blended with oxygenates such as alcohol or an ether compound to meet
clean air standards. Your McCulloch engine is designed to
operate satisfactorily on any gasoline intended for automotive use including oxygenated gasolines.
5-5. FUEL AND LUBRICATION SYMBOLS
Gasoline and Oil
Mix 40:1
6 - STARTING/STOPPING INSTRUCTIONS
6-1.STARTING A COLD ENGINE (Above 55˚F)
Mix the bottle of 2-cycle oil (included) with 1 gallon of unleaded gasoline (less than 30 days old). Combine them in a separate container using a 40:1 ratio. Pour into fuel tank.
1. Squeeze throttle (A) and push throttle lock (B) to
advance throttle for starting. (Figure 6-1A)
2. Pump “primer bulb” (C) 10 times. (Figure 6-1B)
3. Move choke lever to Choke “1”.(Figure 6-1C)
4. With the unit on the ground, hold the top assist handle
and step on the bottom of the frame with foot. Pull
starter rope 6 times. (Figure 6-1D)
NOTE: The unit uses the Smooth Pull
which significantly reduces the effort required to start the
engine. You must pull the starter rope out far enough to
hear the engine attempt to start. There is no need to pull
the rope briskly--there is no harsh resistance when pulling.
Be aware that this starting method is vastly different from
(and much easier than) what you may be used to.
5. Move choke lever to “2” (Fig. 6-1E)
6. Pull starter rope again 1~6 times (Fig. 6-1F)
7. The engine should start. After 30 sec. Move choke to
“3”.(Fig. 6-1G)
8. Squeeze throttle and release to disengage lock ; Unit
is now at idle. (Fig. 6-1A)
NOTE: If engine fails to start after repeated attempts,
refer to Troubleshooting section.
NOTE: Always pull starter rope straight out. Pulling starter
at an angle will cause rope to rub against the eyelet. This
friction will cause the rope to fray and wear more quickly.
Always hold starter handle when rope retracts. Never
allow rope to snap back from extended position. This
could cause rope to snag or fray and also damage the
starter assembly.
B
TM
starting system,
D
6-1C
6-1D
6-1E
D
A
6-1A
C
6-1B
6-1F
6-1G
87
6 - STARTING/STOPPING INSTRUCTIONS
6-2. IMPORTANT IDLING INFORMATION
In some cases due to operating conditions (altitude, temperature etc.) your blower may need a slight adjustment
to the idle speed.
After warm up, If unit does not Idle after restarting 2
times, follow these steps to adjust idle.
1. Locate the idle adjustment screw (E) on the carbure-
tor (Fig. 6-2).
2. Using a Phillips or slotted screwdriver - turn screw 1/4
to 1/2 turn clockwise (to the right). Unit should then
idle properly.
E
6-2
6-4. STARTING A WARM ENGINE (Engine has
been stopped for no more than 15-20 minutes).
1. Set throttle (see step 1 for starting a cold engine),
choke “3”, pull starter rope.
2. If engine does not start, or starts and then stops
after 5 rope pulls, follow procedure “STARTING A
COLD ENGINE”.
6-3. STOPPING THE ENGINE
Emergency Stopping Procedure. When it is necessary
to stop blower engine immediately, DEPRESS the OFF
“STOP ” switch until the engine stops completely (Fig.
6-3).
Normal Stopping Method. For normal stopping, release
trigger and allow engine to return to idle speed. Then
DEPRESS the OFF “STOP ” switch until the engine
stops completely. (Fig. 6-3)
6-3
7 - OPERATING INSTRUCTIONS
7-1. BLOWER OPERATIONS
WARNING
Because of flying debris, always wear American National
Standards Institute approved shielded safety glasses or
face shield when operating blower.
WARNING
Before using your blower, review Safety Precautions in
your User Manual, and all regulations for operation of the
unit. These precautions and regulations are for your protection.
CAUTION
DO NOT operate the blower with other people or animals
in the immediate vicinity. Allow a minimum of 50 feet (15
meters) between operator and other people or animals.
1. Use the blower for trees, shrubs, flower beds, and
hard-to-clean areas.
2. Use the unit around buildings and for other normal
cleaning procedures.
3. Use the blower around walls, overhangs, fences, and
screens.
4. We recommend that a face mask be worn when operating blower in dusty areas.
5. Stand away from the debris, at a distance that will easily allow you to control the direction of blown debris.
Never blow debris in direction of bystanders.
6. To control velocity of airstream, blower can be operated at any speed between idle and full throttle.
Experience with the unit will help you determine the
amount of airflow necessary for each application.
7. Operate power equipment only at reasonable hours-not early in the morning or late at night when people
might be disturbed. Comply with times listed in local
ordinances.
8. To reduce sound levels, limit the number of pieces of
equipment used at any one time.
9. Operate power blowers at the lowest possible throttle
speed to do the job.
10. Check your equipment before operation, especially the
muffler, air intakes and air filters.
11. Use rakes and brooms to loosen debris before blowing.In dusty conditions, slightly dampen surfaces when
water is available.
12. Conserve water by using power blowers instead of
hoses for many lawn and garden applications, including areas such as gutters, screens, patios, grills, porches and gardens.
13. Watch out for children, pets, open windows or freshly
washed cars, and blow debris safely away.
14. Use intermediate tube plus nozzle of your choice so the
airstream can work close to the ground.
15. After using blowers and other equipment, CLEAN UP!
Dispose of debris in trash receptacles.
7-2. OPERATION INSTRUCTIONS
1. Follow the instructions “STARTING A COLD
ENGINE”.
2. Once unit is running, place unit on your back by slipping arms through the shoulder straps as if your were
putting on a jacket (Figure 7-2A).
3. When preparing to clear an area of debris, always
position yourself so that you can control the direction
debris will be blown .
4. The control handle and the flexibility of the blower
tube assembly will allow you to clear the most hard-toreach areas. (Fig. 7-2B)
5. The hand grip, throttle trigger, throttle lock and ignition
on/off switch are all mounted on a swivel handle that
offers a wide range of operating positions and comfort
(Fig. 7-2C).
7-2A
7-2B
7-2C
109
8 - MAINTENANCE INSTRUCTIONS
8-1. MAINTENANCE SCHEDULE
Perform these required maintenance procedures at the frequency stated in the table. These procedures should also
be a part of any seasonal tune-up.
NOTE: Maintenance, replacement, or repair of the emission control devices and system may only be performed by
a McCulloch or other qualified service dealer.
A good preventive maintenance program of regular inspection and care will increase life and improve performance of your
chain saw. This maintenance checklist is a guide for such a program.
Cleaning, adjustment, and part replacement may be required, under certain conditions, at more frequent intervals than those
indicated.
WARNING
To prevent serious injury, never perform maintenance or
repairs with unit running. Always service and repair a cool
unit. Disconnect the spark plug wire to ensure that the unit
cannot start.
CUSTOMER RESPONSIBILITY
MAINTENANCE CHECKLIST
ITEM BEFORE EACH USE 10 20
CHECK FOR LOOSE SCREWS/
NUTS/BOLTS
AFTER
EACH USE
HOURS OF
OPERATION
CLEAN OR REPLACE AIR FILTER
REPLACE FUEL FILTER
REPLACE SPARK PLUG
INSPECT SPARK ARRESTER SCREEN
INSPECT FUEL HOSES
INSPECT TUBES
11
8 - MAINTENANCE INSTRUCTIONS
8-2. AIR FILTER
To Clean Air Filter:
1. Remove cover (A) by depressing clip on top of cover
and lift filter (B) from air box (Fig. 8-2A & Fig. 8-2B).
2. Wash filter in soap and water. DO NOT USE GASO-
LINE!
3. Air dry filter and cover.
4. Reinstall filter.
NOTE: Replace filter if frayed, torn, damaged or unable to
be cleaned.
A
A
8-3A
C
8-2A
B
8-2B
8-3. FUEL CAP / FUEL FILTER
NOTE: Keep vent (A) on fuel cap clean of debris (Fig. 83A).
Fuel Filter:
1. Completely remove fuel cap from fuel tank (B) to be
able to remove fuel filter (D) from tank. Use a piece of
wire (C) with a hook formed at the end to pull filter out
of tank. (Fig. 8-3B)
2. Pull filter (D) off with a twisting motion. (Fig. 8-3C)
3. Replace fuel filter (D). (Fig. 8-3C)
NOTE: Never operate the blower without the fuel filter.
Internal engine damage could result!
B
8-3B
D
8-3C
8-4. IDLE ADJUSTMENT
The carburetor was pre-set at the factory for optimum performance. If further adjustments are necessary take your
blower to a McCulloch or other qualified service dealer.
12
8 - MAINTENANCE INSTRUCTIONS
8-5. SPARK PLUG
1. To remove spark plug (A) (Fig. 8-5A) for cleaning or
replacement: make sure engine is off, spark plug is
cool, then grasp spark plug boot firmly and remove
from spark plug. Remove spark plug with correct spark
plug tool. Inspect, clean or replace as needed.
2. Spark plug gap = .025" (.635mm) (Fig. 8-5B).
3. Torque to 120 inch pounds (12 to 15 N•m). Connect
spark plug boot.
4. If needed, replace spark plug with Champion RZ7C or
equivalent.
A
8-5A
.025" (.635mm)
Spark
Plug
8-6. STORAGE
Failure to follow these steps may cause varnish to form in
the carburetor which can cause difficult starting or permanent damage following storage.
1. Perform all the general maintenance recommended in
the Maintenance Section of your User Manual.
2. Clean exterior of engine and blower tubes.
3. Drain fuel from the fuel tank by running the unit dry or
by removing the fuel cap and tipping the motor housing/fuel tank over and draining oil/fuel mixture into a
container with the same 2-cycle fuel mixture.
4. After fuel is drained, start engine.
5. Run engine at idle until unit stops. This will purge the
carburetor of fuel.
6. Allow engine to cool (approx. 5 minutes).
7. Using a spark plug wrench, remove the spark plug.
8. Pour 1 teaspoon of clean 2-cycle oil into the
combustion chamber. Pull starter rope slowly several
times to coat internal components. Replace spark plug.
9. Store unit in a cool, dry place away from any source of
ignition such as an oil burner, water heater, etc.
8-7. REMOVING A UNIT FROM STORAGE
1. Remove spark plug.
2. Pull starter rope briskly to clear excess oil from combustion chamber.
3. Clean and gap spark plug or install a new spark plug
with proper gap. (Fig. 8-5B)
4. Prepare unit for operation.
5. Fill fuel tank with proper fuel / oil mixture. See Fuel and
Lubrication Section.
8-5B
9 - TROUBLESHOOTING THE ENGINE
PROBLEM
Unit won’t start or starts but will not
run.
Unit starts, but engine has low
power.
PROBABLE CAUSE
Incorrect starting procedures.
Incorrect carburetor mixture adjustment
setting.
Fouled spark plug
Fuel filter plugged.
Incorrect lever position on choke.
Dirty spark arrester screen.
Dirty air filter.
Incorrect carburetor mixture adjustment
setting.
CORRECTIVE ACTION
Follow instructions in the User Manual.
Have carburetor adjusted by an
Authorized Service Center.
Clean / gap or replace plug.
Replace fuel filter.
Move to RUN position.
Replace spark arrester screen.
Remove, clean and reinstall filter.
Have carburetor adjusted by an
Authorized Service Center.
Engine hesitates.
No power under load.
Runs erratically.
Smokes excessively.
Incorrect carburetor mixture adjustment
setting.
Incorrectly gapped spark plug.
Incorrect carburetor mixture adjustment
setting.
Incorrect fuel mixture.
Have carburetor adjusted by an
Authorized Service Center.
Clean / gap or replace plug.
Have carburetor adjusted by an
Authorized Service Center.
Use properly mixed fuel (40:1 mixture).
1413
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