Cats on their way out??

[Will]

After I run my car, I always look under it to make sure everythings alright (im paranoid, this car doesnt like me) Anyhow, I noticed that at least on one of the cats, i can see the heat coming off of it, and i dont remember it doing that before. And im pretty sure there is a rattle occasionally. Both of the shields are in place as well. If the cats are clogged, will it be ok just to punch them out? I would get a new y-pipe, but funds are lacking right now. Thanks, Will

 

[SHO#7]

An easy way to check converters other than banging on them is... Check the temp before and after the converter. If it's alot hotter before the converter and cool after the cat, then chances are they are clogged. But you didn't mention performance. Other than they look hot, are you having problems. They will get hot, hot, hot. On my old 93 MTX when they went bad, she had no power. And the exhaust stunk like rotten eggs. Hope this helps

 

[Bizzy]

Will, the cats will get very hot within a matter of minutes of the engine running. I found this out the hard way. So heat is normal...if they get glowing red (more visible at night) it's for sure time for a change.

If you bang on them with the palm of your hand and you hear a rattle sound from inside the cat material is breaking up. Mine were chuncked up pretty badly so it sounded like a metal nut bouncing around inside.

You can gut them and all will be fine, just make sure you get all of it and be prepared for the car to be louder than it was before.

Good luck!

<small>[ August 05, 2003, 02:07 PM: Message edited by: Bizzy ]</small>

 

[sdpatt]

To operate properly to oxidize (burn) the extra hydrocarbons in the exhaust stream, the cats must be at least 750F. When doing their oxidation and reduction reactions, the cats will have a temperature increase of 100F between the inlet and outlet temperatures. So yes, they are supposed to be quite hot. That is why there are heat shields on them.

If you tap them gently with a broomstick, do you hear any rattling? If yes, not good. Replace the damaged cat at a muffler shop. If not, you are paranoid.

 

[Dave Ladely]

I got rid of the cats, but passed emissions with room to spare as this engine is very efficient compared to most and as long as it passes emissions, it is not a smog creator any more than any other engine that passes emissions. Washington does not do a visual inspection, and they were happy with my results.