Klutch MIG 140i User manual

READ & SAVE THESE INSTRUCTIONS
MIG 140i 120V Inverter MIG Welder
Owner’s Manual
WARNING: Read carefully and understand all ASSEMBLY AND OPERATION
INSTRUCTIONS before operating. Failure to follow the safety rules and other basic safety
precautions may result in serious personal injury.
Item #74220

Page 2 of 31
Thank you very much for choosing a Klutch® product!
For future reference, please complete the owner’s record below:
Serial Number/Lot Date Code: ________________________________
Purchase Date: ____________________________________________
Save the receipt, warranty, and this manual. It is important that you read
the entire manual to become familiar with this product before you begin
using it.
This welder is designed for certain applications only. Northern Tool &
Equipment is not responsible for issues arising from modification or
improper use of this product such as an application for which it was not
designed. We strongly recommend that this product not be modified
and/or used for any application other than that for which it was designed.
For technical questions, please call 1-800-222-5381.

Page 3 of 31
Table of Contents
Intended Use..........................................................................................................................................4
Packaging Contents..............................................................................................................................4
Technical Specifications......................................................................................................................4
Important Safety Information...............................................................................................................5
Specific Operation Warnings...............................................................................................................6
Main Parts of MIG140i.........................................................................................................................11
Setting Up Equipment.........................................................................................................................12
Before Each Use..................................................................................................................................18
Operating Instructions........................................................................................................................19
After Each Use.....................................................................................................................................25
Maintenance ........................................................................................................................................25
Troubleshooting..................................................................................................................................26
Parts Diagram......................................................................................................................................28
Parts List..............................................................................................................................................28
Replacement Parts..............................................................................................................................29
Limited Warranty.................................................................................................................................30

Page 4 of 31
Intended Use
The Klutch MIG 140i is an inverter-powered, wire feed welder for flux core and MIG welding. It comes
complete with a regulator and gas hose for easy connection for MIG. Directly connect this unit to a
120V household power. It is designed to weld materials as thin as 24 gauge all the way up to 3/16" in
a single pass.
Welding with a flux core wire gives the operator the flexibility to use this wire feed welder for mobile
applications, including outdoor applications. The flux core wire does not require the use of a separate
shielding gas which can be blown away by the wind in outdoor applications. Since flux core welding
does not use shielding gas, the operator will not have to have shielding gas bottles, or use the
regulator and gas hose.
Welding with a MIG wire does require the use of a bottle of shielding gas. See the Set-Up guide inside
the wire compartment door for recommendations on shielding gas based on the material you are
welding. MIG welding is limited to indoor applications or applications where the influence of wind can
be controlled to prevent the shielding gas from blowing away. MIG welding allows you to weld thinner
materials without burn-through. It also creates a much cleaner weld with less spatter and no slag. The
result is little post-weld cleaning of the weld joint.
This unit is intended to be used on a 20-amp 120V AC circuit without the use of an extension cord. If
an extension cord is necessary for your application, use the appropriate size and length of extension
cord that will handle 20 amps the entire length of the extension. We highly recommend talking with a
qualified electrician for cord size recommendations.
High frequency, inverter-based welding is more efficient and provides better control than non-inverter
welding machines.
Packaging Contents
•MIG 140i Welder
•MIG Torch
•Ground Cable/Clamp
•MIG Nozzle
•10 ft. Gas Hose
•Dual Gauge Regulator
•Flux Core Nozzle
•.030 Contact Tips
•Owner’s Manual
Technical Specifications
Property
Specification
Power Supply
120V, 20A, 50/60 Hz, Single Phase
No-Load Voltage
60V DC
Output Range - MIG
30A/15.5V to 90A/18.5 DC
Duty Cycle
30% @ 90A
Suggested Wire
Steel, Stainless Steel
Suggested Wire Diameter
.023, .030, .035
Dimensions
16-7/10ʺx 7-6/10ʺx 10-6/10ʺ
Weight
19.4 lb.

Page 5 of 31
Important Safety Information
⚠WARNING
•Read and understand all instructions. Failure to follow all instructions may result in serious injury
or property damage.
•The warnings, cautions, and instructions in this manual cannot cover all possible conditions or
situations that could occur. Exercise common sense and caution when using this tool. Always be
aware of the environment and ensure that the tool is used in a safe and responsible manner.
•Do not allow persons to operate or assemble the product until they have read this manual and
have developed a thorough understanding of how it works.
•Do not modify this product in any way. Unauthorized modification may impair the function and/or
safety and could affect the life of the product. There are specific applications for which the product
was designed.
•Use the right tool for the job. DO NOT attempt to force small equipment to do the work of larger
industrial equipment. There are certain applications for which this equipment was designed. It will
be a safer experience and do the job better at the capacity for which it was intended. DO NOT use
this equipment for a purpose for which it was not intended.
•Industrial or commercial applications must follow OSHA requirements.
⚠WARNING
WORK AREA SAFETY
•Inspect the work area before each use. Keep work area clean, dry, free of clutter, and well-lit.
Cluttered, wet, or dark work areas can result in injury. Using the product in confined work areas
may put you dangerously close to cutting tools and rotating parts.
•Do not use the product where there is a risk of causing a fire or an explosion; e.g., in the presence
of flammable liquids, gases, or dust. The product can create sparks, which may ignite the
flammable liquids, gases, or dust.
•Do not allow the product to come into contact with an electrical source. The tool is not insulated
and contact will cause electrical shock.
•Keep children and bystanders away from the work area while operating the tool. Do not allow
children to handle the product.
•Be aware of all power lines, electrical circuits, water pipes, and other mechanical hazards in your
work area. Some of these hazards may be hidden from your view and may cause personal injury
and/or property damage if contacted.

Page 6 of 31
⚠WARNING
PERSONAL SAFETY
•Stay alert, watch what you are doing, and use common sense when operating the tool. Do not use
the tool while you are tired or under the influence of drugs, alcohol, or medication. A moment of
inattention while operating the tool 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, or long hair can be caught in moving
parts. Air vents on the tool often cover moving parts and should be avoided.
•Wear the proper personal protective equipment when necessary. Use ANSI Z87.1 compliant safety
goggles (not safety glasses) with side shields, or when needed, a face shield. Use a dust mask in
dusty work conditions. Also use non-skid safety shoes, hardhat, gloves, dust collection systems,
and hearing protection when appropriate. This applies to all persons in the work area.
•Do not overreach. Keep proper footing and balance at all times.
⚠CAUTION
WELDER USE AND CARE
•Do not force the welder. Products are safer and do a better job when used in the manner for which
they are designed. Plan your work, and use the correct product for the job.
•Check for damaged parts before each use. Carefully check that the product will operate properly
and perform its intended function. Replace damaged or worn parts immediately. Never operate the
product with a damaged part.
•Store the product when it is not in use. Store it in a dry, secure place out of the reach of children.
Inspect the tool for good working condition prior to storage and before re-use.
•Use only accessories that are recommended by the manufacturer for use with your product.
Accessories that may be suitable for one product may create a risk of injury when used with
another tool. Never use an accessory that has a lower operating speed or operating pressure than
the tool itself.
•Keep guards in place and in working order. Never operate the product without the guards in place.
Specific Operation Warnings
⚠WARNING
Your Welding Environment
•Keep the environment you will be welding in free from flammable materials.
•Always keep a fire extinguisher accessible to your welding environment.

Page 7 of 31
•Always have a qualified person install and operate this equipment.
•Make sure the area is clean, dry, and ventilated. Do not operate the welder in humid, wet, or
poorly ventilated areas.
•Always have your welder maintained by a qualified technician in accordance with local, state and
national codes.
•Always be aware of your work environment. Be sure to keep other people, especially children,
away from you while welding.
•Keep harmful arc rays shielded from the view of others.
•Mount the welder on a secure bench or cart that will keep the welder secure and prevent it from
tipping over or falling.
⚠WARNING
Your Welder’s Condition
•Check the ground cable, power cord, and welding cable to be sure the insulation is not damaged.
Always replace or repair damaged components before using the welder.
•Check all components to ensure they are clean and in good operating condition before use.
⚠CAUTION
During Operation
Do not operate the welder if the output cable, electrode, torch, or any accessories are wet. Do
not immerse them in water. These components and the welder must be completely dry before
attempting to use them.
•Follow the instructions in this manual.
•Keep the welder in the OFF position when not in use.
•Connect ground lead as close to the area being welded as possible to ensure a good ground.
•Do not allow any body part to come in contact with the welding electrode if you are in contact with
the material being welded, ground, or electrode from another welder.
•Do not weld if you are in an awkward position. Always have a secure stance while welding to
prevent accidents. Wear a safety harness if working above ground.
•Do not drape cables over or around your body.
•Wear a full coverage helmet with appropriate shade (see ANSI Z87.1 safety standard) and safety
glasses while welding.
•Wear proper gloves and protective clothing to prevent your skin from being exposed to hot metals,
UV, and IR rays.
•Do not overuse or overheat your welder. Allow proper cooling time between duty cycles.

Page 8 of 31
•Keep hands and fingers away from moving parts.
•Do not point the torch at a body part of yours or anyone else’s.
•Always use this welder in the rated duty cycle to prevent excessive heat and failure.
⚠WARNING
Electrical Shock
Electric arc welders can produce a shock that can cause injury or death. Touching electrically live
parts can cause fatal shocks and severe burns. While welding, all metal components connected to the
wire are electrically hot. Poor ground connections are a hazard, so secure the ground lead before
welding.
•Wear dry protective apparel: coat, shirt, gloves and insulated footwear.
•Insulate yourself from the work piece. Avoid contacting the work piece or ground.
•Do not attempt to repair or maintain the welder while the power is on.
•Inspect all cables and cords for any exposed wire and replace immediately if found.
•Use only recommended replacement cables and cords.
•Always attach the ground clamp to the work piece or work table as close to the weld area as
possible.
•Do not touch the welding wire and the ground or grounded work piece at the same time.
•Do not use a welder to thaw frozen pipes.
⚠WARNING
Fumes and Gases
•Do not use the plasma cutter in the presence of gasoline, diesel, propane, or other flammable
liquids. Sparks created from the cutter may ignite liquids or fumes, causing an explosion and
serious injury or death.
•Fumes emitted from the welding process displace clean air and can result in injury or death.
•Do not breathe in fumes emitted by the welding process. Make sure your breathing air is clean
and safe.
•Work only in a well-ventilated area or use a ventilation device to remove welding fumes from the
environment where you will be working.
•Do not weld on coated materials (galvanized, cadmium plated or containing zinc, mercury, or
barium). They will emit harmful fumes that are dangerous to breathe. If necessary use a ventilator,
respirator with air supply, or remove the coating from the material in the weld area.
•The fumes emitted from some metals when heated are extremely toxic. Refer to the material

Page 9 of 31
safety data sheet for the manufacturer’s instructions.
•Do not weld near materials that will emit toxic fumes when heated. Vapors from cleaners, sprays,
and degreasers can be highly toxic when heated.
⚠WARNING
UV and IR Arc Rays
The welding arc produces ultraviolet (UV) and infrared (IR) rays that can cause injury to your
eyes and skin. Do not look at the welding arc without proper eye protection.
•Always use a helmet that covers your full face from the neck to top of head and to the back of
each ear.
•Use a lens that meets ANSI standards and safety glasses. For welders under 160 amps output,
use a shade 10 lens; for above 160 amps, use a shade 12. Refer to the ANSI standard Z87.1 for
more information.
•Cover all bare skin areas exposed to the arc with protective clothing and shoes. Flame-retardant
cloth or leather shirts, coats, pants, or coveralls are available for protection.
•Use screens or other barriers to protect other people from the arc rays emitted from your welding.
•Warn people in your welding area when you are going to strike an arc so they can protect
themselves.
⚠WARNING
Fire Hazards
Do not weld on containers or pipes that contain or have had flammable, gaseous, or liquid
combustibles in them. Welding creates sparks and heat that can ignite flammable and
explosive materials.
•Do not operate any electric arc welder in areas where flammable or explosive materials are
present.
•Remove all flammable materials within 35 feet of the welding arc.
•Take precautions to ensure that flying sparks do not cause fires or explosions in hidden areas,
cracks, or areas you cannot see.
•Keep a fire extinguisher close in the case of fire.
•Wear garments that are oil-free with no pockets or cuffs that will collect sparks.
•Do not have on your person any items that are combustible, such as lighters or matches.
•Keep work lead connected as close to the weld area as possible to prevent any unknown,
unintended paths of electrical current from causing electrical shock and fire hazards.

Page 10 of 31
•To prevent any unintended arcs, cut the wire back to ¼" stick out after welding.
⚠CAUTION
Hot Materials - Welded materials are hot and can cause severe burns if handled improperly.
•Do not touch welded materials with bare hands.
•Do not touch the torch nozzle after welding until it has had time to cool down.
⚠CAUTION
Electromagnetic Field
•Electromagnetic fields can interfere with various electrical and electronic devices such as
pacemakers.
•Consult your doctor before using any electric arc welder or cutting device.
•Keep people with pacemakers away from your welding area when welding.
•Do not wrap cable around your body while welding.
•Wrap the torch and ground cable together whenever possible.
•Keep the torch and ground cables on the same side of your body.
H.F. RADIATION can cause interference!
•High-frequency (H.F.) can interfere with radio navigation, safety services, computers, and
communications equipment.
•Have only qualified persons familiar with electronic equipment perform this installation.
•The user is responsible for having a qualified electrician promptly correct any interference problem
resulting from the installation.
•If notified by the FCC about interference, stop using the equipment at once.
•Have the installation regularly checked and maintained.
•Keep high-frequency source doors and panels tightly shut, keep spark gaps at correct setting, and
use grounding and shielding to minimize the possibility of interference.
ARC welding can cause interference!
•Electromagnetic energy can interfere with sensitive electronic equipment such as computers and
computer-driven equipment such as robots.
•Be sure all equipment in the welding area is electromagnetically compatible.
•To reduce possible interference, keep weld cables as short as possible, close together, and down
low, such as on the floor.
•Locate welding operation 100 yards from any sensitive electronic equipment.