Zenoah ZHM800 User manual

70239160000 (E0/A1602)
Zenoah Flail Mower
Instruction Manual
Applicable models: #16001 and later
When lending or
borrowing the mower
as rental equipment,
make sure this manual
is provided with it.
WARNING
Improper use of this mower may result in serious injury or death. Operators and service managers must read and
understand the contents of this manual before operating, inspecting or servicing the mower. To enable reference
by all operators and service managers who deal with the mower, store this manual in the storage space provided
on the mower, enabling it to be read periodically.

To Users
Thank you for your purchase of a Zenoah flail mower.
This instruction manual provides information on how to handle the mower and the precautions to observe
when using it.
Before using the mower, be sure to read this manual and become thoroughly familiar with its content to
ensure proper and safe use of the mower.
After reading this manual, keep it in a readily accessible location next to the mower.
Mower Restrictions
This mower may not be operated on public roads. Zenoah assumes no liability for accidents or
infractions involving the mower on public roads.
This product has been created for use as a hammer knife mower, and must not be used for other
purposes.
The mower does not have a light for night work, and must not be used at night.
Registration Information
Purchase date
Mower
Model name
Serial No.
Engine
Model name
Serial No.
The information above will be needed when ordering consumable parts, so should be entered in the
fields provided.
The mower model name and serial No. are shown on a label (model No. label) on the mower.
Engine serial No.
Engine model name
Label (model No.)

1
SAFETY PRECAUTIONS ..........................................................................
1
2
NAMES OF COMPONENTS ......................................................................
10
3
SAFETY LABEL AND OPERATION LABEL POSITIONS ...........................
12
4
PART HANDLING AND OPERATION ........................................................
14
5
OPERATING THE MOWER
1. Driving the Mower .........................................................
19
2. Cutting Grass ................................................................
20
3. Shutting Down the Mower .............................................
20
4. Transporting the Mower .................................................
21
5. Storing the Mower .........................................................
22
6
PERIODIC INSPECTIONS ........................................................................
23
7
PRE-WORK INSPECTIONS
1. Inspections Done Before Starting the Engine ................
26
2. Inspections Done With the Engine Running ..................
29
8
TROUBLESHOOTING ...............................................................................
30
9
OTHER 1. Main Specifications .......................................................
31
2. Main Consumable Parts ................................................
32
10
WIRING DIAGRAM ....................................................................................
33
CONTENTS

-1-
Failure to observe the precautions given in this section could result in injury or death, or cause accidents
or damage to the mower.
Before operating the mower, read these precautions and the information in the labels on the mower. Be
sure to follow these instructions carefully to ensure work is done safely and correctly.
The items below marked with this symbol are important safety precautions that must always be
followed.
Instruction manual
Conditions for starting work
1. SAFETY PRECAUTIONS
Precaution items that will result in death or serious injury if not followed.
Precaution items that may result in death or serious injury if not followed.
Precaution items that may result in injury if not followed.
Operation procedures or conditions that may result in damage to the mower if not followed.
IMPORTANT
Read the instruction manual
Read the instruction manual before using the mower and become thoroughly
familiar with the mower’s methods of operation and precautions. Practice the
methods of operation on a flat area with good visibility before starting actual work.
Store the instruction manual in a readily accessible location next to the mower.
When lending the mower to others, thoroughly explain how to handle it and
make sure the borrower reads the instruction manual.
If not followed:
Accidents caused by incorrect usage methods may result.
The mower must not be operated by following person in following situations
Do not allow person who applies to any of the followings to use this mower.
When overwork, illness, medication, or a similar influence will adversely affect operator
concentration
While intoxicated
While pregnant
Anyone under the age of 18
Anyone unfamiliar with how to handle the mower
Instruction
manual
DANGER
WARNING
CAUTION
DANGER
WARNING

-2-
Clothing
Mower alteration
Inspection
Wear appropriate work clothing
Wear appropriate close-fitting work clothing while working.
Do not wear clothing that is too large, or has flowing or billowing material.
Do not wear a headband, neck scarf or towel around the waist.
Wear a long-sleeved shirt.
Wear long trousers.
Wear a helmet or work hat.
Wear non-slip shoes.
If not followed:
Improper clothing may interfere with mower operation, become caught in
rotating parts, or cause slips and falls. 

Wear protective eyewear
Wear protective eyewear since dust or grass clippings may fly into the air while working and enter
eyes, or tree branches may poke eyes.
Never alter the mower
Altering the mower is strongly discouraged. Never alter the mower.
When replacing parts for consumable part replacement or repair, always use genuine Zenoah parts.
If not followed:
May lead to accidental death, injuries or mower damage.
The warranty will be voided.
Have all mechanical problems repaired before use
Stop operation immediately if the blades strike a foreign object, or if you experience abnormal
sounds, abnormal vibrations or abnormal odor while working. Inspect the mower parts and contact
your place of purchase or a Zenoah sales office.
Have all mechanical problems repaired before use.
If not followed:
May lead to mower damage or failure.
OK
A
NG
DANGER
WARNING
WARNING
WARNING

-3-
Stop operation immediately if abnormal vibrations occur
The hammer knives rotate at high speed and create abnormal vibrations if they become unbalanced.
Unbalanced hammer knives are dangerous to the operator and anyone nearby, and can damage
mower parts.
If you experience abnormal vibrations, immediately stop operation, inspect the mower and have it
repaired.
If not followed:
May lead to mower damage or failure.
Prevent the cutter from falling when inspecting or servicing it
Take steps to prevent the cutter from falling when inspecting or servicing the blades with the cutter
raised.
If not followed:
May cause accidents or injuries from being trapped by the cutter.
Always attach the covers
Always return the covers to the original position when removed for inspection or cleaning.
Replace covers that have become misshapen.
If not followed:
May result in accidents or injuries caused by being pulled into rotating parts.
Wait for hot parts to cool before starting inspection or cleaning
Wait for hot parts such as the engine block, muffler and rotating parts to cool completely before starting
inspection or cleaning work.
If not followed:
May result in burns.
Inspect and clean the mower
Always inspect and clean the mower before use.
Also carry out periodic inspection and cleaning. (See p. 22)
Inspection and cleaning should be done on a flat, stable
surface with the engine stopped.
If not followed:
May result in accidents, injuries, mower failure or mower runaway.
WARNING
WARNING
CAUTION
CAUTION
CAUTION
STOP

-4-
Fuel
Always clean the mower after use on the same day
Always clean the mower after use, on the same day that it was used. After washing the mower with
water, always wipe the mower dry and apply machine oil or grease to sliding parts to prevent rusting.
Start the engine to expel water that has accumulated inside the fan cover.
If not followed:
Rust may prevent normal mower operation and lead to failure.
Use compressed air with caution when cleaning
When using compressed air for cleaning, flying dirt or debris may cause major injuries.
When using compressed air to clean parts such as elements, wear protective gear such as protective
eyewear and dustproof gloves.
If not followed:
Flying dirt or debris may lead to major injuries.
Never fuel the mower near open flames.
Never have an open flame when supplying fuel to the mower or when fuel is
nearby.
Do not smoke or bring open flames near the mower.
Always fuel the mower with unleaded automotive gasoline. Do not
use leaded gasoline, poor quality gasoline, degraded gasoline, or
gasoline that was stored in a plastic container for an extended
period.
If not followed:
Fuel may ignite and start a fire.
The engine may be adversely affected, leading to declining engine performance or failure.
Wait for the engine to cool before supplying fuel or oil to the mower
Never remove the fuel tank cap, or supply fuel or oil to the mower while the engine is running or hot.
If not followed:
Fuel may ignite and start a fire.
DANGER
DANGER
CAUTION
CAUTION

-5-
In sealed indoor spaces
Transport
Watch out for fuel leaks
The fuel hose is made of rubber, making it susceptible to UV and other types of damage. The hose
needs to be inspected, since fuel will leak if it is damaged. If you find damage to the hose, contact
your place of purchase or a Zenoah sales office to have it replaced. Always use genuine Zenoah
parts when replacement is needed.
If not followed:
Fuel may ignite and start a fire.
Make sure the fuel tank cap is attached properly, and wipe off spilled fuel
After fueling the mower, fasten the fuel tank cap securely and completely wipe off any spilled fuel.
If not followed:
Fuel may ignite and start a fire.
Fuel the mower with unleaded automotive gasoline
Always fuel the mower with unleaded automotive gasoline. Do not use leaded gasoline, poor quality
gasoline or degraded gasoline.
If not followed:
Engine parts may be adversely affected, leading to declining engine performance or failure.
Watch out for the engine exhaust gas
The engine exhaust gas is toxic. Do not start the engine in a closed
indoor space.
Start the engine in a well-ventilated outdoor area. Provide adequate
ventilation when starting the engine indoors is unavoidable.
If not followed:
Exhaust gas poisoning may result, leading to accidental death.
Drive the mower at low speed on a flat, stable surface when loading or
unloading it
Drive the mower at low speed on a flat, stable surface when loading or unloading it from a truck or van.
If not followed:
The mower may become unbalanced, leading to falls or other accidents.
DANGER
DANGER
WARNING
CAUTION
CAUTION

-6-
Work precautions
Never operate the side clutch levers on a running board
When loading or unloading the mower from a truck or van, drive the mower at the lowest speed, on a
fixed course that prevents course changes on the running board. Never operate the side clutch levers
or drive clutch lever to change course or stop. Do not set the gear shift lever to the neutral position.
If an emergency situation arises, stop the engine.
If not followed:
May lead to falls or other accidents.
Fasten the mower to the truck securely with ropes.
When transporting the mower in a truck or van, lock the mower’s wheels and fasten it securely in place
with ropes.
If not followed:
The mower may fall out of the vehicle.
Watch out for obstacles behind you when reversing
Pay adequate attention to obstacles behind you when reversing the mower.
If not followed:
The operator may become trapped by the obstacle, or suffer a fall resulting in injury or death.
Keep people away from the mower while working
Stop operation if people or pets come near the mower
while you are working.
If not followed:
Stones or other foreign objects struck by the running blades may
fly out and cause death or injury.
Use a running board of adequate strength, length and width.
The running board used to load the mower aboard a truck or van must have a loading capacity of at
least 0.5 t, be long enough to tilt the mower by no more than 14° (at least 4 times the truck bed
height), and have a width of at least 30 cm.
If not followed:
May lead to falls or other accidents.
DANGER
DANGER
CAUTION
CAUTION
CAUTION

-7-
The blades are invisible when rotating at high speed
The blades are invisible when they are rotating at high speed. Do not place hands or feet inside the
cutter housing when the blades are rotating.
If not followed:
May lead to amputated limbs or other injuries.
Always ensure the safety of the surrounding area before starting
the engine
Before starting the engine, always ensure the safety of the people
and objects in the surrounding area, and make sure that the drive
clutch lever and blade clutch lever are both in the OFF position.
If not followed:
May lead to accidents such as mower runaway.
Remove any trash from around the engine
Inspect the mower every day before starting work to make sure no grass, trash or other foreign objects
are adhering to the engine cooling air intake, air cleaner air intake or muffler area.
If not followed:
May lead to declining engine performance, overheating or fires.
Set the blade clutch to the OFF position when moving the mower
When moving the mower under its own power, always set the blade clutch to the OFF position to stop
the blades rotating.
If not followed:
The blades may unexpectedly strike foreign objects, damaging the mower or causing injuries
from flying objects.
Always keep the work site clean
Always keep the work site clean.
Remove any stones, empty cans, nails, wire, trash and other debris.
If not followed:
The blades may strike foreign objects, damaging the mower or
causing injuries from flying objects.
DANGER
WARNING
WARNING
WARNING
WARNING

-8-
Precautions when working on gradients
Never start, stop or turn the mower suddenly, or speed excessively
Start and stop the mower slowly. Decrease the mower’s speed sufficiently before turning on uneven
land.
If not followed:
May lead to falls, toppling accidents or mower damage.
Before leaving the mower unattended, place it on flat ground and
stop the engine
Before leaving the mower unattended, place it on a flat, stable surface and stop the engine with the
drive clutch and blade clutch both in the OFF position.
If not followed:
The mower could start moving, leading to an accident.
Never operate the mower at night
Do not operate the mower in dark or poor-visibility locations.
If not followed:
Accidents or injuries could result.
Be able to operate the mower calmly during emergency situations
Incorrect operation methods lead to accidents. To ensure you will be
able to stop the mower calmly if an emergency situation arises, pay
careful attention when operating the mower and become thoroughly
familiar with its operation methods.
If not followed:
A lack of familiarity with the mower’s operation methods could
result in the wrong decision in an emergency, preventing
hazard avoidance and resulting in unexpected accidents.
Do not completely fill the fuel tank
Fuel may spill from the fuel tank when driving the mower on a gradient, so do not fill the tank
completely. Use an amount of fuel that will avoid spilling.
If not followed:
Could result in fires caused by spilled fuel.
DANGER
WARNING
WARNING
WARNING
CAUTION

-9-
Storage
Gradient pitch should be no more than 15° left or right
Working on gradients is very dangerous.
Gradients should have a pitch or no more than 15° left or right.
Do not use the mower on gradients steeper than 15°.
If not followed:
May lead to falls, toppling accidents or mower damage.
Use low speed when driving on gradients
Lower speed adequately when driving on gradients or uneven land, and before turns.
If not followed:
May lead to falls, toppling accidents or mower damage.
Never park the mower on gradients
Do not park the mower on a gradient.
If not followed:
May lead to accidents.
Wait until the mower has cooled enough before using a sheet cover
Wait until the engine block, muffler and other hot parts have cooled sufficiently before covering the
mower with a sheet cover.
If not followed:
May lead to fires.
Store the mower indoors
Store the mower indoors. If outdoor storage is unavoidable, cover the mower with a sheet cover to
protect it from rain.
If not followed:
The mower’s life will be shortened.
DANGER
WARNING
WARNING
WARNING
CAUTION

-10-
* The front, rear, left and right directions in these diagrams apply when the cutter housing is at the front and
the handles are at the rear.
2. NAMES OF COMPONENTS
Mower right
Front guard
Mower rear
Mower left
Mower front
Handle
Gear shift lever
Engine
Fender
Front cover
Front wheel
Front wheel arm
Rear wheel
Cutter housing

-11-
Throttle lever
Side clutch lever (left)
Side clutch lever (right)
Engine stop switch
Parking brake lever
Blade clutch lever
Drive clutch lever
Cut height adjustment handle
Belt cover

-12-
To ensure safe operation, the positions of the safety labels and operation labels provided on the mower
are shown below.
Keep these labels clean and undamaged. Replace any labels that become damaged or lost with new
labels.
3. SAFETY LABEL AND OPERATION LABEL POSITIONS
70932260005 (KW56256AA)
Handling precaution label
70236561100
Label (belt size)
70236561000
Label (cut height)
CAUTION
Hot muffler caution
Touching may cause
burn injuries.
WARNING
Exhaust gas warning
Running engine indoors or
in poorly ventilated area is
hazardous and a health risk.
DANGER
No open flames
・Stop engine when
fueling.
・Risk of fire.
・Keep flames away from
fuel supply opening.
Belt size chart
Engine to transmission
LB37
1
Engine to intermediate
shaft
B58
2
Intermediate shaft to
cutter shaft
LB36
2
Cut height adjustment
Longer
Shorter
WARNING
Always keep hands and
feet clear
●This cover encloses rotating
parts. Placing hands or feet
inside will result in injuries.
DANGER
Failure to observe the
precautions below may
lead to injuries
●Before using the mower,
read this operation
manual carefully to
thoroughly familiarize
yourself with the mower’s
operation and
management methods.
●Always carry out the
specified pre-work and
periodic inspections.
●Always stop the engine
before inspecting or
fueling the mower, or
replacing parts.
●Fasten the fuel tank cap
securely, and wipe off any
spilled fuel.
●Check that the drive
clutch and blade clutch
are OFF before starting
the engine.
●When parking the mower,
park it on a flat, stable
surface, stop the engine
and set the parking brake.
●When using a running
board, it must be long
enough to tilt the mower
by no more than 14°, and
have a width of at least 30
cm.
●Drive the mower at low
speed when loading or
unloading it, since its
center of gravity will be
unstable. Secure the
mower with ropes after
loading it aboard a truck.
●The front end of the
mower may rise up off the
ground if you start moving
at high speed. Use a
lower engine speed when
starting to move.
unleaded gasoline
70236560600
Label (flammable item)
CAUTION
Flammable item
caution
●Grass or other
flammable items
accumulating
around the
engine can lead
to fires and major
accidents.

-13-
70236560300
Label (unbalanced loads)
70236560200
Label (caution in front)
70236560400
Label (flying objects)
70236560900
Label (gear shift lever)
70236560800
Label (blade clutch lever)
70236560700
Label (drive clutch lever)
Caution in front
Check safety
DANGER
● Stones or other debris may
fly out of the mower while
working. Check that no people
or vulnerable objects are in
front of the mower while
working.
● Contact with rotating parts
may result in injuries. Keep
away from rotating parts.
WARNING
The front guard and blade
cover are designed to
protect the operator and
prevent foreign objects
from flying out of the
mower. These parts
should always be
replaced with new ones if
they become damaged.
WARNING
Stop operation immediately and
inspect/repair the mower if it loses
balance or starts vibrating due to
blades becoming damaged or
falling off.
Gear shift lever
Medium speed
High speed
Low speed
reverse
Drive clutch lever
Parking brake lever
ON
OFF
OFF
ON
Squeeze to turn
the mower right
Side clutch lever
Blade clutch lever
ON
OFF
Squeeze to turn
the mower left
Side clutch lever

-14-
1. Drive clutch lever
Used to move or stop the mower.
Moving the drive clutch lever to the top (ON) position
moves the mower forward if the gear shift lever is at the
low, medium or high speed setting, or backward if the
gear shift lever is at the reverse setting.
Moving the lever to the bottom (OFF) position stops the
mower.
The lever springs back to its original position if not
moved completely into place.
Drive clutch lever
The front end of the mower may rise up off the ground if you start moving at high speed. Use a lower
engine speed when starting to move.
Check that the drive clutch lever is in the OFF position before starting the engine.
The engine will not start if the drive clutch lever is not in the OFF position.
2. Blade clutch lever
Used when cutting grass.
Moving the blade clutch lever to the top (ON) position
starts the cutter shaft. Moving the lever to the bottom
(OFF) position stops the cutter shaft.
The lever springs back to its original position if not
moved completely into place.
Blade clutch lever
Always set the lever to the OFF position when not cutting grass (such as when moving or storing the
mower).
Check that the drive clutch lever is in the OFF position before starting the engine.
The engine will not start if the blade clutch lever is not in the OFF position.
4. PART HANDLING AND OPERATION
ON
OFF
ON
OFF
WARNING
WARNING

-15-
3. Parking brake lever
Used when parking the mower.
Moving the parking brake lever to the ON position sets
the parking brake. Moving the lever to the OFF position
releases the parking brake.
Moving the drive clutch lever to the ON position when
the parking brake lever is in the ON position
automatically switches the parking brake lever to the
OFF position.
Parking brake lever
The parking brake is only designed to prevent the mower from rolling while parked.
Do not attempt to use the parking brake as a driving brake.
Parking the mower on gradients is dangerous. Do not park the mower on a gradient.
4. Gear shift lever
Selects the drive speed and operation speed when
cutting grass.
There are three forward speeds (low, medium and
high), and one reverse speed.
Use only the low or medium speed setting when cutting
grass.
Gear shift lever
Move the gear shift lever until it clicks into place. Not moving the lever completely into place is
dangerous since the mower will not be in gear.
Move the drive clutch lever to the OFF position to stop the mower before switching gears.
If you have difficulty switching gears, try again after moving the gears in the transmission by moving
the drive clutch lever slightly toward the ON position and back again.
ON
OFF
WARNING
WARNING

-16-
5. Throttle lever
Increases or decreases the engine speed.
Operate the throttle lever by turning it in the arrow
directions shown at right.
Throttle lever
6. Choke knob
Helps start the engine.
Pull the choke knob out when starting the engine.
Once the engine has started, push the knob back in
while monitoring the engine’s operation.
Do not operate the choke knob in summer or
when the engine is hot.
Choke knob
7. Side clutch levers
Used to change the mower’s travel direction to the
right or left.
Squeezing the right side clutch lever turns the mower
right. Squeezing the left side clutch lever turns it left.
Raising the front wheels slightly off the ground makes
turning easier.
The mower may turn suddenly to face downhill
when turning on a gradient, so exercise ample
caution when operating the levers.
Left side clutch lever Right side clutch lever
High
speed
Low
speed
Pull
IMPORTANT
WARNING