How to weld Exhaust Pipe Successfully

This article is a complete guide on “How to weld Exhaust Pipe Successfully“. The welding of a car or vehicle exhaust pipe is utilized when a crack appears in the pipe, or it’s rusted that requires replacement.

It is possible to resolve the issue independently, but this requires a knowledge of the appropriate type of welding machine to use and whether the solution is suitable for the specific scenario. If you’re looking to repair a crack in your car or vehicle’s exhaust pipe, welding is a great solution.

To start, you’ll need to clean and cut the affected area. Then, you can use small tacks to hold the pipe in place before welding. It’s important to use a low amperage setting on your welder to avoid burning through the metal.

While welding an exhaust pipe may seem challenging, it can actually be a straightforward process if you have the right knowledge and technique.

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By reading this article, you’ll gain a solid understanding of how to effectively weld exhaust pipes.

What you need to Weld an Exhaust Pipe?

It’s evident that it’s time for a repair when the exhaust’s sound changes significantly. So, it’s crucial to check if the part is repairable and then proceed with the welding process.

To get started, you’ll need the following list of tools and materials:

  • A welding machine (we’ll discuss which one is the best to choose later);
  • Screwdrivers, hammers, wrenches, and other automotive tools;
  • An angle grinder, along with a set of cutting and stripping discs;
  • Sandpaper, metal brushes;
  • Pieces of metal sheets (with a thickness of 1 to 2 millimeters);
  • Special heat-resistant paint;
  • Pieces of thin-walled pipes of the suitable diameter.

Only the damaged areas are treated during the repair process, which is referred to as local repair.

The punctured area is cut out, and it’s also a good opportunity to inspect the condition of the internal components, as they may be damaged and require restoration as well.

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Which Welder is best for welding Exhaust Pipe for a Car?

For welding an Exhaust Pipe, a semi-automatic welder (MIG or Gasless MIG-Flux core) is a suitable option.

This method gives less heat compared to others, as the welding is carried out in a protective welding gas environment with wire feed.

The metal heating is kept to a minimum, and the wire thickness is typically between 0.8 to 1 mm.

For those who are skilled in stick welding, it’s also a good option. However, it requires precise and continual movement of the electrode to avoid burning through the thin metal and damaging the exhaust system.

Welding Rod for Exhaust Pipe Welding

Most of the Exhaust pipes are made from carbon steel and you can weld them using E6011 and E6013 rod as well with ER70S-6 filler wire.

For stainless steel exhaust pipe welding, you can use E309L welding rod.

How to Weld Exhaust Pipe?

Welding an exhaust pipe can seem like a daunting task, but with the right tools and techniques, it can be done relatively easily.

How to weld Exhaust Pipe

Welding an exhaust pipe is necessary when a crack or hole has developed, and repairing it is necessary to maintain the performance and safety of your vehicle. The process of welding an exhaust pipe involves:

  1. Prepare the area: Clean the exhaust pipe thoroughly, removing any rust, dirt, or debris. Cut out any damaged sections of the pipe and make sure that the edges are smooth.
  2. Tack weld the pipes together: Tack welding is the process of welding small spots to hold the pipes together temporarily. Tack welding helps prevent the pipes from moving while you make the final welds.
  3. Set up the welder: Choose a welding machine suitable for your welding experience and the thickness of the pipes. Make sure the machine is set up correctly, with the appropriate voltage and amperage for the job.
  4. Weld the pipes: Start welding the pipes together, working from one end to the other. Make sure to keep the welding torch moving continuously to avoid overheating and burning through the metal.
  5. Clean up the welds: After welding, remove any slag or debris from the welds using a metal brush. Sand the welds to remove any rough spots and to ensure a smooth surface.
  6. Paint the exhaust pipe: Apply heat-resistant paint to the entire pipe to protect it from rust and other environmental factors.
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Note: Always wear appropriate personal protective equipment, including gloves, a welding helmet, and a long-sleeved shirt, while welding.

Stick welding Exhaust Pipe


6012 Welding Rod

6013 Welding Rod
E6013 rod

Stick welding of exhaust pipe is good option and it can be welded successfully with stick welding with some considerations such as:

  1. Use low penetration welding rods (E6012 & E6013) as exhaust pipes usually have low thickness.
  2. Weld with stringer beads.
  3. Use low welding heat and don’t overheat during welding.
  4. Weld using smaller diameter rods.
  5. You can use Lap joint also instead of groove joint to weld exhaust pipe. For this you need to find a ring/ pipe that can overlap joining area. Alternatively, you can cut the pipe in 2 pieces and weld over the leaking area.

Before you Weld exhaust pipe attached to car, make sure:

Before beginning the welding process, it is important to ensure the safety of the vehicle by turning off the ignition and disconnecting the battery terminals.

When welding on a vehicle, it is important to take the following precautions to ensure your safety and the safety of the vehicle:

  1. Wear protective gear: Always wear appropriate personal protective equipment such as gloves, a welding helmet, and protective clothing to protect yourself from sparks, heat, and fumes.
  2. Disconnect the battery: Disconnect the battery terminals to avoid electrical shock and to protect the electrical system of the vehicle.
  3. Ventilation: Ensure proper ventilation to remove fumes and protect yourself from inhaling toxic fumes.
  4. Fire safety: Keep a fire extinguisher or fire-retardant materials nearby in case of a fire.
  5. Ground the vehicle: Ground the vehicle to a secure, grounded surface to avoid electrical shock.
  6. Use the correct welding technique: Use the correct welding technique and equipment for the specific metal you are welding to ensure a safe and effective repair.
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Cold welding of Exhaust Pipe

J-B Weld is a two-part epoxy that can be used as an alternative to traditional welding methods for repairing exhaust pipes.

J-B Weld extreme heat is ideal for small cracks and holes in the exhaust pipe, as it can be applied quickly and without the need for heat.

To use J-B Weld to repair an exhaust pipe, first make sure that the damaged area is clean and free of any rust or debris.

Then, mix equal parts of the J-B Weld resin and hardener together, following the manufacturer’s instructions.

Apply the mixed J-B Weld to the damaged area of the exhaust pipe, making sure that it is evenly spread and that the entire crack or hole is filled.

It is important to allow sufficient curing time for the J-B Weld to fully set and harden. This can vary depending on the manufacturer’s recommendations, but typically ranges from 4 to 8 hours.

In order to ensure that the J-B Weld repair can withstand the high temperatures that are present in an exhaust system, it is important to choose a high temperature J-B Weld.

These products are formulated to resist heat and maintain their strength and stability even at high temperatures.

Once the J-B Weld has fully cured, the repair can be sanded and smoothed to restore the surface of the exhaust pipe to its original condition.


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