Everything about MIG Welder Repair Tips & Tricks

Like other welders, MIG welders can also have some problems. When you’re buying a welder, you must have the knowledge of solving the common problems of it. If you don’t have enough knowledge about MIG welder repair, suddenly appeared problems will interfere with your work. This will be a waste of time.

Many times, you have to go to a professional to solve small problems. So that useless money will be spent. And when you know how to fix your welder yourself, it will save your time and money, and also make you much more skillful.
I will discuss MIG welder repair in detail today and give you the right guidelines so that you can fix your welder yourself.

Some Common MIG Welder Problems

Basic Problems

Welding Problems

Advanced Welding Problems

MIG Welder Troubleshooting

Machine Starting Problem


Because of wrong input voltage, blown up of fuse, having problems in the circuit, or overheating the machine can create a problem for starting.


  • At first, switch the machine appropriately.
  • Verify the input voltage and follow the manual to avoid this problem.
  • If the machine gets overheated, then switch off it and wait for cooling down.
  • For the cause of blown up of fuse, you must replace the fuse.

Machine Fuse Blows

Cause:If the machine starts without any problem and suddenly the fuse creates a problem, then there has a defective fuse. This can lead to short circuit. In addition, the other cause may be the wick is so small.


  • Solve the short circuit problem.
  • Or, change the fuse with a bigger one if the first fuse is too small.

MIG welding light doesn’t work

Cause:Due to no or low airflow, the machine’s equipment will not start. Then the light also doesn’t work.


  • If the welding light doesn’t work, but the machine lead is working, check the safety LED.
  • IF the safety LED is okay, check by resetting the safety button.
  • Check the airflow also. If there is low airflow, the machine will not work.
  • Put your machine in purge mode to turn on the airflow.

If The Polarity Switch Doesn’t Work

Cause:The polarity switch stops working if the switch decrepit or the welder is under load.


  • Change the polarity switch.
  • Check that you aren’t using it at under load condition.

Electrode Holder’s Excess Heating Up

Cause: Because of loose connection or having set an irregular duty cycle, the Electrode holder will excessively heat up.


  • Tight the connection.
  • Alternatively, if an irregular duty cycle causes the problem, change with the proper size of it.

Electrical Shocks

Cause: Electrical shocks may cause if the grounding of the frame is improper.


  • Follow the instruction of grounding the frame, as explained in the manual.

Overheating of welding cable:

Cause: When the cable is very old and in the defective condition, the cable will heat up very quickly. And also for the improper duty cycle that can happen.


  • Replace the cable with proper conditions.
  • And set the duty cycle properly.

Welding Problems

Inappropriate wire feeding

Cause: When there is an inappropriate wire feeding problem, this may create many problems in welding. Worn driver rolls cause inappropriate wire feeding problems.


  • Clean the driver roll regularly. Make sure that you are removing all the dirt of the liner.
  • Replace the driver roll of the welder if it is necessary.

Low welding

Cause:If the welding gun’s tip worn out, it can cause flat welding.


  • Replace the tip at once.


Cause:Due to insufficient gas flow, another common welding defect named porosity occurs.


  • PLug in the gas nozzle properly if it is not.
  • Also, check that the wire connection is appropriate or not.

Shrinkage Crash On The Weld

Cause: When the wire is pale, that can cause a shrinkage crash on the weld. Having small follicles in the wire can also cause this problem.


  • You will not face this problem if the follicle is of proper size.
  • Make sure that there is no rust in the welding area.

Lateral Cracks On The Weld

Cause: Because of fast welding speed or high arc voltage or low current lateral cracks on the weld can occur.


  • Maintain a constant welding speed.
  • Keep the current and the arc voltage constant.

Excess Spatter

Cause: Excess CO2 or improper impedance can cause excess spatter. This is a mass welding defect. This problem may also occur due to high voltage.


  • Use a gas heater to avoid this problem.
  • Also, use appropriate voltage preventing excess spatter.

If you are interested, you can read 10 Best MIG Welder’s Review here.

Advanced Welding Troubles

Weld Metal Porosity

Inappropriate Surface conditions:

Cause:The surface defiling with rust, grease, or oil can cause metal porosity. An open surface can also cause this.


  • Clean the material properly and regularly to avoid the contamination of the surface.

Absorbency Problem

Weld Metal Porosity

Gas Coverage:

Cause: When your welder’s gas shield is not appropriate, that can cause a porosity problem. When this is inappropriate, the gas shield can’t protect the weld puddle adequately. And when shielding gas exchange with the air, the porosity occurs.


  • Attach the gas hose properly to the equipment. It will prevent the chance of porosity.

Mismatching of Base Metal

Cause: Mismatching of the base metal can make porosity problems also. If the metal you are welding is not the same baking bar material you are using, then porosity can occur.


  • Of course, use the same baking bar material of the of as the metal you’re going to weld to prevent this problem.

Inappropriate Bead Problems

Lacking Input Heat

Cause: Using improper input power can cause this problem.


Fix the input power correctly.

  • Follow the thickness of the metal while fixing the input power to avoid this problem.
  • The wrong techniques in welding and using small cable can also cause a Bead problem. So, be careful about the welding technique and size of the cable.
  • The problem of Fusion Shortage

The problem of Fusion Shortage

Cold Lapping

Cause: Cold lapping occurs for lacking fusion. The wire contacts with the welding pool and the wire melts.


  • Use the voltage in the proper range.
  • Also, check the amperage whether it is in the right forum or not to avoid the cold lapping problem.
  1. Defective wire Delivery Problems

Contact Tips

Cause: Because of faulty wire delivery, contact tips can occur. For excess spatter or touching on the welding paddle, contact tips can get obstructed.


  • Change the contact tips to solve this problem.
  • Must use the contact tips with the proper size.

Inappropriate Size of Gun Liner


Short wire delivery occurs when the size of the gun liner is improper. Extending wire can also create this problem.


  • Obviously, use the proper size of the gun liner.
  • To keep the gun liners free from dust, regularly clean it.
  • Change the ships frequently also if necessary to avoid this problem.

Worn Out Gun

Cause: Wire feeding problem can occur for a worn outgun.


  • Immediately replace the worn-out gun with a new one after noticing this problem.

Drive Roll

Cause: Excessive drive roll pressure can cause problems in wire feeding. If the drive roll is very loose, the wire feeding will stop. And, when the drive is very tight, then it will crash suddenly. So, both the loose and tight drive roll can cause a problem.


  • For avoiding this problem, make sure that the drive roll pressure is not too loose or not too tight.

If you take care of your MIG welder properly, you can use it for a long time without any problem. Always keep your welder clean so that there are no problems. Take precautionary measures before the problem arises; this is the wise thing to do. This is a perfect guide to MIG welder repair. It will help you very much with MIG welding troubleshooting. I guess, now you are more confident in MIG welding machine repair.

Knowing your MIG welder’s problems and solutions to those problems, now save your time, save money, and make yourself more efficient.

Patrick Germain

Patrick Germain

Patrick Germain is a professional Home Improvement Advisor. Also studied Residential Construction. Also, love to write and share more about authentic home improvement and residential construction. Feel free to reach him and ask more about related topics.

Share on facebook
Share on twitter
Share on linkedin

Leave a Reply

Your email address will not be published. Required fields are marked *