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How to Plug a Leak in a Car's Catalytic Converter

by Robert Good

A catalytic converter is a device on a vehicle the reduces the toxicity of emissions from the engine. The catalytic converter is on the underside of the vehicle and looks like a metal box with two pipes on each side. You can use steel putty to seal any hole or crack in the catalytic converter. This will form a permanent seal that will last a long time. You can buy the putty at any auto store.

Step 1

Get under vehicle so that you can see the catalytic converter. The catalytic converter will be connected to the exhaust pipe toward the muffler.

Step 2

Locate the leak while the vehicle is running by feeling around the catalytic converter for exhaust gas blowing out of it. Shut down the engine and allow the catalytic converter to cool down.

Place a piece of steel putty onto the leak. Push on the putty using your finger to seal the leak. Smooth the putty using your finger to make it flush with the catalytic converter. Allow the putty to dry for four hours before starting the engine.

Warning

  • Allow the catalytic converter to completely cool before you apply the putty to avoid serious burns.

Items you will need

  • Steel putty

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