Hot Catalytic Converter
Thread Starter
Intermediate
Joined: Feb 2004
Posts: 47
Likes: 0
From: Sacramento CA
Hot Catalytic Converter
What would cause a Catalytic Converter to get red hot?
I was just out in the garage adjusting my choke and I let the car idle until it got warm enough to open the choke. I noticed a burning smell and got down and looked under the car and the Catalytic Converter was glowing red.
Is it going bad? The car just passed a smog check last week so I don’t think it was bad then.
Thanks
Jim
I was just out in the garage adjusting my choke and I let the car idle until it got warm enough to open the choke. I noticed a burning smell and got down and looked under the car and the Catalytic Converter was glowing red.
Is it going bad? The car just passed a smog check last week so I don’t think it was bad then.
Thanks
Jim
Race Director
Joined: Nov 1999
Posts: 10,643
Likes: 8
From: Foxfield CO 1970 Convertible
It was probably just working overtime while the choke was on. It's pretty normal for catalytic converters to be hot enough to start fires. How is it the rest of the time when you are driving??
Friend Request Magnet
Joined: Dec 2005
Posts: 50,242
Likes: 149
From: ♫ ♪ ♫♫ ♪ ♫ ♪♪ ♫
In my experience/opinion; if it got glowing hot at just enough time for choke to open...its clogged...whether it passed emissions or not.
Remove guts in it (if legal).
By-pass it (if legal).
Or install a free flow convertor if your state regulates you to have a convertor.
And yes; they will start fires if anything touches it, especially when parking on grass.
Usually there is a power loss, and loss of fuel mileage when this happens.
Good luck, and keep an eye on it.
Jim
Remove guts in it (if legal).
By-pass it (if legal).
Or install a free flow convertor if your state regulates you to have a convertor.
And yes; they will start fires if anything touches it, especially when parking on grass.
Usually there is a power loss, and loss of fuel mileage when this happens.
Good luck, and keep an eye on it.
Jim
Advanced
Joined: May 2005
Posts: 95
Likes: 0
From: '70 Coupe - SoCal
Originally Posted by Strats-N-Vettes
In my experience/opinion; if it got glowing hot at just enough time for choke to open...its clogged...whether it passed emissions or not.
Remove guts in it (if legal).
By-pass it (if legal).
Or install a free flow convertor if your state regulates you to have a convertor.
And yes; they will start fires if anything touches it, especially when parking on grass.
Usually there is a power loss, and loss of fuel mileage when this happens.
Good luck, and keep an eye on it.
Jim
Remove guts in it (if legal).
By-pass it (if legal).
Or install a free flow convertor if your state regulates you to have a convertor.
And yes; they will start fires if anything touches it, especially when parking on grass.
Usually there is a power loss, and loss of fuel mileage when this happens.
Good luck, and keep an eye on it.
Jim
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Melting Slicks
Joined: May 2001
Posts: 2,131
Likes: 4
From: May help you? You can sure as hell try!
You're running rich. The cat is hot because it is trying to burn all the unburned fuel from running rich. I don't remember if 78's have an O2 sensor but if you do, you might look in to changing it. It's hot because it is working, don't change it.
Burning Brakes
Joined: Aug 2002
Posts: 1,146
Likes: 10
From: Scottsboro Alabama
Besides being a fire hazard, those things pollute the air. Ever get behind a vehicle that has one thats accelerating to climb a hill? It spews fumes out that smells exactly like a beer and pickled egg fart. 
Not good for the environment or your health. 
Not good for the environment or your health.
Instructor
Joined: Sep 2003
Posts: 135
Likes: 0
From: Estevan SK
You want to smell bad eggs? Smell a brand new chevy at your local dealership sometime that just came off the truck! My mom was looking at the new montanas today because the lease is up on her old one and she almost left the dealership the thing smelt so bad haha. Must need to break them in or something. No need for cats here in saskatchewan, or mufflers in the rural areas for that matter haha.
Burning Brakes
Joined: Aug 2005
Posts: 1,126
Likes: 0
From: Hudson Falls, N.Y. 76 Vette Modified L-48
Originally Posted by SHAKERATTLEROLL
If it gets red hot replace it. It is clogged up.
It may be working with a rich condition, but it should NOT glow red that far back from the manifold...I agree with SHAKE
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Originally Posted by kb2fzq
It may be working with a rich condition, but it should NOT glow red that far back from the manifold...I agree with SHAKE
If it was clogged you would also feel it under acceleration. You would hit a certain RPM and the engine would feel like its stuck.
I tend to agree with the "rich condition".
But you may have a rich condition and a bad cat. How does the car perform???
Jim
Racer
Joined: Mar 2005
Posts: 445
Likes: 0
From: SAN DIEGO(SANTEE) CA.
Originally Posted by kb2fzq
It may be working with a rich condition, but it should NOT glow red that far back from the manifold...I agree with SHAKE
but that's just MHO