How to Repair a Dented Exhaust Pipe

Lead Image
  • 2-4 hours
  • Intermediate
  • 0-200
What You'll Need
Automotive style block plugs
Air compressor or blow torch

Having a dent in your exhaust pipe can lead to serious problems. If you see a dent in your pipe, you need to straighten the damage at once. Dents constrain the flow of air in the pipe. Straightening the pipe removes tension in the blocked area. You can use dry ice on the pipes to remove dents. This practice applies to most pipes. Not all dents can be easily removed with this method. Some will require more work to straighten the dented parts. Using a torch to remove a dent is a popular yet dangerous method in removing dents.

Step 1 - Clean the Pipe

You need to remove any form of residue inside the pipe. Use a hose and run clean water into the exhaust system. Do this two or three times to make sure the system is free from gas deposits. Remove all gas deposits prior to operation.

Step 2 - Pressurize the Pipes

Use automotive style block plugs to seal the exhaust system. Put the plugs at the far end in order to be attached to the vice grips of the pipe. This will help the pipe from exploding under pressure. Make sure that the pipes are connected to the air compressor. Leaks are unavoidable during this process. Switch on the air compressor and check the pressure reaches from 80 to 120 psi. The amount of pressure will depend on the pipe’s damage.

Step 3 - Heat the Metal

Make sure the pipes glow red once you start heating the pipes up with a torch. Be cautious not to melt the metal. The use of heat will make the dents come out. Heat the pipes slowly. Be careful not to go near the heated area. Remember, wear protective gloves or use rags to prevent your hands from getting burnt. You will need to use goggles once you start hammering the pipes.

Step 4 - Hammer the Dents

Get your hammer and tap the dents out in a slow, circular motion. You will use a hammer to shape the dented pipes. Do this slowly. It may seem tedious at first, especially if you are not used to handling automotive procedures. Hammering the pipes in quick motion could result in damaging the pipes. Hammer until everything is smooth.

Step 5 - Cool Down the Pipe

After hammering, wait for the pipe to cool down. This may take a few minutes. Once the pipe is cooled down, release air pressure, and get your rotary wire wheel to sand the pipes. Use steel wool for the hard-to-reach areas. Continue sanding until the metal is shiny and smooth again. It’s optional if you want to put a layer of automotive paint on. Just make sure all the dents are smooth before you apply paint. Overlooked dents are obvious once you start painting the pipes. You will have to start all over again.