Echo CS-310 User manual

X7533271300
© 11/23 ECHO Incorporated
Operator’s
Manual
CS-310
Chainsaw
The engine exhaust from this product contains chemicals
known to the State of California to cause cancer, birth defects,
or other reproductive harm.
Read and understand all provided literature before
use. Failure to do so could result in serious injury.
Note: This product complies with CAN ICES-2/NMB-2.

TABLE OF CONTENTS CS-310
2 X7533271300
© 11/23 ECHO Incorporated
TABLE OF CONTENTS
Introduction................................................................................................................. 3
Servicing Information.................................................................................................. 3
Parts and Serial Number.................................................................................... 3
Service ............................................................................................................... 4
ECHO Consumer Product Support .................................................................... 4
Product Registration........................................................................................... 4
Additional Literature ........................................................................................... 4
Safety ......................................................................................................................... 5
Manual Safety Symbols and Important Information ........................................... 5
International Symbols......................................................................................... 6
Personal Condition and Safety Equipment ........................................................ 8
Rules for Safe Operation.................................................................................. 12
Correct Use of Chain Brake ............................................................................. 13
Emission Control .(Exhaust & Evaporative) ............................................................ 19
EPA Emissions Control Information ................................................................. 19
Description ............................................................................................................... 20
Contents................................................................................................................... 22
Assembly.................................................................................................................. 22
Preparation for Use .......................................................................................... 22
Operation.................................................................................................................. 26
Fuel .................................................................................................................. 26
Chain Lubricant ................................................................................................ 29
Winter Operation .............................................................................................. 30
Starting Cold Engine ........................................................................................ 30
Starting Warm Engine ...................................................................................... 32
Running............................................................................................................ 34
Stopping ........................................................................................................... 35
Checking Chain Tension .................................................................................. 35
Chain Lubrication Test...................................................................................... 35
Cutting Instructions .......................................................................................... 36
Guide Bar and Chain Combination .................................................................. 40
Kick GuardTM ................................................................................................... 41
Guide Bar ......................................................................................................... 41
Saw Chain........................................................................................................ 41
Maintenance............................................................................................................. 42
Skill Levels ....................................................................................................... 42
Maintenance Intervals ...................................................................................... 43
Carburetor Adjustment ..................................................................................... 44
Air Filter............................................................................................................ 46
Spark Plug........................................................................................................ 46
Check Fuel System .......................................................................................... 46
Fuel Filter ......................................................................................................... 47
Oil Filter............................................................................................................ 47
Guide Bar ......................................................................................................... 48
Sprocket ........................................................................................................... 48
Cooling System Cleaning................................................................................. 49
Spark Arrester Muffler ...................................................................................... 49
Spark Arrester Screen...................................................................................... 50
Exhaust Port Cleaning ..................................................................................... 50
Setting the Saw Chain...................................................................................... 51
Troubleshooting........................................................................................................ 54
Storage..................................................................................................................... 55
Storage After Use............................................................................................. 55
Specifications ........................................................................................................... 56
Product Registration................................................................................................. 58

CS-310 INTRODUCTION
X7533271300 3
© 11/23 ECHO Incorporated
INTRODUCTION
Specifications, descriptions, and illustrative material in this literature are as
accurate as possible. Specifications are subject to change without notice.
Illustrations might include optional equipment and accessories, and might
not include all standard equipment. Your equipment might appear slightly
different than pictured equipment.
Read and understand all provided literature.
Literature contains specifications and
information for safety, operation,
maintenance, storage, and assembly
specific to this product. Scan QR codes for
more information.
For additional literature, including safety manuals where applicable, or
questions regarding terms used in this manual, visit:
https://www.echo-usa.com/manuals
OR
https://www.shindaiwa-usa.com/manuals
SERVICING INFORMATION
Parts and Serial Number
Genuine ECHO parts and
assemblies for your ECHO products
are available only from an
Authorized ECHO Dealer. When
you do need to buy parts, always
have the model number and serial
number of the unit with you. For
future reference write them in the
space provided below.
Model No. _____________________ Serial No. ____________________

SERVICING INFORMATION CS-310
4 X7533271300
© 11/23 ECHO Incorporated
Service
Service of this product during the warranty period must be performed by an
Authorized ECHO Service Dealer. For the name and address of the
Authorized ECHO Service Dealer nearest you, ask your retailer or call:
1-800-432-ECHO (3246). Dealer information is also available on our Web
Site www.echo-usa.com. When presenting your unit for Warranty service/
repairs, proof of purchase is required.
ECHO Consumer Product Support
If you require assistance or have questions concerning the application,
operation, or maintenance of this product, call the ECHO Consumer
Product Support Department at 1-800-432-ECHO (3246) from 8:00 a.m. to
5:00 p.m. (Central Standard Time) Monday through Friday. Before calling,
please know the model and serial number of your unit.
Product Registration
Register your ECHO equipment online at www.echo-usa.com or by filling
out the product registration sheet included in this manual. Registering your
product confirms warranty coverage and provides a direct link to ECHO if
we find it necessary to contact you.
Additional Literature
In addition to finding information online, information is available from your
Authorized ECHO Service Dealer, or by contacting ECHO Incorporated,
400 Oakwood Road, Lake Zurich, IL 60047, 1-800-432-ECHO (3246).

CS-310 SAFETY
X7533271300 5
© 11/23 ECHO Incorporated
SAFETY
Manual Safety Symbols and Important Information
Throughout this manual and on the product itself, you will find safety alerts
and helpful, informational messages preceded by symbols or key words.
The following is an explanation of those symbols and key words and what
they mean to you.
The safety alert symbol accompanied by the word “DANGER”
calls attention to an act or condition which WILL lead to serious
personal injury or death if not avoided.
The safety alert symbol accompanied by the word “WARNING”
calls attention to an act or condition which CAN lead to serious
personal injury or death if not avoided.
The safety alert symbol accompanied by the word “CAUTION”
calls attention to an act or condition which might lead to minor
or moderate personal injury if not avoided.
The enclosed message provides information necessary for the
protection of the unit.
Note: This enclosed message provides tips for use, care and
maintenance of the unit.
CIRCLE AND SLASH SYMBOL
This symbol means the specific action shown is prohibited.
Ignoring these prohibitions can result in serious or fatal injury.

SAFETY CS-310
6 X7533271300
© 11/23 ECHO Incorporated
International Symbols
Symbol Description Symbol Description
WARNING!
Read and follow
all safety
precautions in
the instruction
manual. Failure
to follow
instructions
could result in
serious personal
injury.
Carburetor
Adjustment -
High Speed
Mixture
Wear Eye, Ear,
and Head
Protection.
Carburetor
Adjustment -
Idle Speed
Tip contact may
cause the guide
bar to move
suddenly upward
and backward,
which may cause
serious injury.
Carburetor
Adjustment -
Low Speed
Mixture
Contact of the
guide bar tip with
any object
should be
avoided.
Measured
maximum
kickback value,
without brake,
for approved
bar and chain
combinations.
Both of the
operator’s hands
must be used to
operate the
chainsaw.
Fuel and Oil
Mixture
Hot Surface Chain Oil Fill
H
T
L

CS-310 SAFETY
X7533271300 7
© 11/23 ECHO Incorporated
Note: Not all symbols will appear on your unit.
Chain Brake
Operation
Chain Oiler
Adjustment
Choke Control
“COLD START”
Position (Choke
Closed)
Choke Control
“RUN” Position
(Choke Open)
Purge Bulb
Decompression
Device
STOP /
Momentary
STOP Switch
Symbol Description Symbol Description
STOP
STOP

SAFETY CS-310
8 X7533271300
© 11/23 ECHO Incorporated
Personal Condition and Safety Equipment
Cancer and Reproductive Harm
www.P65Warnings.ca.gov
The muffler or catalytic muffler and surrounding cover
may become extremely hot. Always keep clear of
exhaust and muffler area, otherwise serious personal
injury might occur.
Users of this product risk injury to themselves and others if the
unit is used improperly and/or safety precautions are not
followed. Proper clothing and safety gear must be worn when
operating unit.
Physical Condition
Your judgment and physical dexterity may not be good:
• If you are tired or sick
• If you are taking medication
• If you have taken alcohol or drugs
Operate unit only if you are physically and mentally well.
Eye Protection
◆Eye protection that meets ANSI Z87.1 or CE requirements
must be worn whenever you operate the unit.
◆For additional safety, a full-face shield can be worn over
safety glasses or goggles to provide protection from sharp
branches or flying debris.

CS-310 SAFETY
X7533271300 9
© 11/23 ECHO Incorporated
Hand Protection
Wear sturdy, no-slip, rubber work gloves to improve your grip on the
handles. Gloves also provide protection against cuts and scratches, cold
environments, and reduce the transmission of machine vibration to your
hands.
Hearing and Ear Protection
ECHO recommends wearing personal protective equipment whenever unit
is used.
Breathing Protection
Operators who are sensitive to dust or other common airborne allergens
may need to wear a dust mask to prevent inhaling these materials while
operating unit. Dust masks can provide protection against dust, plant debris,
and other plant matter such as pollen. Make sure the mask does not impair
your vision, and replace the mask as needed to prevent air restrictions.
Proper Clothing
Wear snug-fitting, durable clothing:
• Pants should have long legs, shirts should have long sleeves.
• DO NOT WEAR SHORTS.
• DO NOT WEAR TIES, SCARVES, JEWELRY, or clothing with loose or
hanging items that could become entangled in moving parts or
surrounding growth.
• Keep clothing buttoned or zipped, and keep shirt tails tucked in.
• Wear sturdy work shoes with nonskid rubber soles.
• DO NOT WEAR OPEN TOED SHOES.
• DO NOT OPERATE UNIT WITH BARE FEET.
Keep long hair away from engine and air intake. Retain hair with cap or net.
Heavy protective clothing can increase operator fatigue, which may lead to
heat stroke. Schedule heavy work for early morning or late afternoon hours
when temperatures are cooler.

SAFETY CS-310
10 X7533271300
© 11/23 ECHO Incorporated
The components of this machine generate an electromagnetic
field during operation, which can interfere with some
pacemakers. To reduce the risk of serious or fatal injury,
persons with pacemakers should consult with their physician
and the pacemaker manufacturer before operating this
machine. In the absence of such information, ECHO does not
recommend the use of this machine by anyone who has a
pacemaker.
Extended Operation and Extreme Conditions
Prolonged exposure to cold and/or vibration can result in injury.
Read and follow all safety and operation instructions to
minimize risk of injury. Failure to follow instructions can result
in painful wrist/hand/arm injuries.
It is believed that a condition called Raynaud’s Phenomenon, which affects
the fingers of certain individuals, may be brought about by exposure to
vibration and cold. Exposure to vibration and cold may cause tingling and
burning sensations, followed by loss of color and numbness in the fingers.
The following precautions are strongly recommended, because the
minimum exposure, which might trigger the ailment, is unknown.
• Keep your body warm, especially the head, neck, feet, ankles, hands, and
wrists.
• Maintain good blood circulation by performing vigorous arm exercises
during frequent work breaks, and also by not smoking.
• Limit the hours of operation. Try to fill each day with jobs where operating
the unit or other hand-held power equipment is not required.
• If you experience discomfort, redness, and swelling of the fingers
followed by whitening and loss of feeling, consult your physician before
further exposing yourself to cold and vibration.