How to Weld an Exhaust System Pipe

Welding is a skill that some people take years to perfect, and it can be done in a multitude of different ways. One of the most common and inexpensive methods of welding is MIG welding, which will work perfectly for an exhaust system. Welding two exhaust pipes together will seal the joint and make the exhaust system leak-free. This is a complicated process and should be done by someone with experience in welding; otherwise, you risk injury.

Things You'll Need

  • Jack
  • Jack stands
  • Exhaust clamps
  • Welding helmet
  • Welding gloves
  • MIG welder
  • Jack up the car using a jack and put it on four jack stands. Make sure there is enough room for you to move easily around the underside of the car. Crawl underneath the car and locate the section of exhaust tubing you want to weld. Examine the wall thickness of the tubing.

  • Compare the wall thickness of the tubing with the system setup diagram on the inside cover of the welder. Set your welder to the settings listed for that gauge of metal. These settings will vary with each welder.

  • Clamp the exhaust lines together using the exhaust clamp, making sure to butt the two pieces of exhaust tubing together perfectly. Put on the welding helmet and gloves.

  • Set the ground clamp for the welder on the exhaust. Place the end of the welder approximately 1/8 inch away from the surface of the exhaust. Pull the trigger. Work the puddle you see through the helmet into crescent shapes, working your way back and forth until you have a 1 inch long weld. Repeat the process on the other side of the exhaust clamp.

  • Remove the exhaust clamp then weld the remaining perimeter of the exhaust tubing. Remove the vehicle from the jack stands using the jack.