Catalytic Converter

[91Wagoneerer]

My buddy just got a 87 Grand Wag and needs to get a catalytic converter. It seems his glows orange if he drives it for an extended period of time. That is not good. What is his best bet for getting that problem fixed? How much should he spend?

[The Preacher]

Summit racing has some for around $100.

http://summitracing.com

I need to replace the one on my '77 some time this year. Mine was easy to remove except for the fact that I had to cut the bolts off with a dremmel tool. 4 bolts on one end and it just slides into the muffler on the other. An easy "do it yourself" job. smile.gif

I have been told they come cheaper at other places. It is just that Summit is the only catalogue I am getting right now. :D

[Wagoneer622]

That is definitly not a good thing when it glows. That is sometimes a good indication that the motor is running rich. I had the same problem and it actually burned the carpet infront of my back seat. The inside of the cat was broken apart it just fell out when I pulled it and there were pieces of the honeycomb in the muffler. My problem was my carb was bad, and it was running very rich.

I know CarQuest has the cheap ones that are like $60.00. I used one of those as temporary fix before I swaped motors. It actually flowed really well and didn't give me any problems. I noticed the difference and was working great for almost 6 months. Hope this helps.

[coolram]

Summit is good, also try www.jegs.com (http://www.jegs.com) You have a choice of Dynomax,Random Tech and Catco depending on where you buy from.Also make sure his air pump is working properly or you'll ruin the new convertor in short time.

[talntar]

on a slightly difrent note. if i replace my cat with a cheater for now{no funds right now}what can i do with the line from the pump?

[The Preacher]

Time out!

You guys lost me on the "pump". What are you referring to here?

[coolram]

Talntar you can cap the line off similar to what you would do to a vaccuum line(that's what Iv'e done and the length of exhaust test pipe I used was 18").
Preacher the pump we are referring to is the Air Injection pump(A.I.R.).It takes exhaust gases from the exhaust manifolds(the air tubes connected to the manifolds and routed thru hoses,thru divertor valves)to oxygenate the cat convertor.That's what the small line to the convertor is for.That's why we use 3 way convertor.

[ January 16, 2003, 09:22 AM: Message edited by: coolram ]

[Don in Missouri]

If you cap the air line won't the pump have to constantly pump against the pressure in the capped tube?

Has anybody ever had exhaust manifolds glow on their 360? I've had it happen on both of mine. It is scary when you see it.

[Puvong]

I think changing the Cat will not solve that problem, because the motor is out off tuning. Actually, the Cat shows and works properly when you see it glows red. It seems like your buddy's truck runs too rich/lean or electrical system problems "misfire" that causes excessive HC through the Cat.

[coolram]

Opps..good point.Need to remove the belt to the air pump also if you cap the line to the convertor.Iv'e seen exhaust manifolds glow.Clogged cat will do this or a really lean mix.

[The Preacher]

Originally posted by coolram:
Preacher the pump we are referring to is the Air Injection pump(A.I.R.).It takes exhaust gases from the exhaust manifolds(the air tubes connected to the manifolds and routed thru hoses,thru divertor valves)to oxygenate the cat convertor.That's what the small line to the convertor is for.That's why we use 3 way convertor.3 way converter?? Does this apply to a '77?

I have the tubes on my manifolds but I don't seem to have a separate line running to or from my cat.

Sorry, but I am still not all the way with you on this one.

This is important for me to get straight since I am running a cheater right now myself and my chero is running bad.

[bvibert]

Originally posted by Don in Missouri:
Has anybody ever had exhaust manifolds glow on their 360? I've had it happen on both of mine. It is scary when you see it.No but I had that happen to the manifold on the 258 in my old J10. We were tooling around in my buddies fields one winter doing doughnuts and stuff. The J10 was in the process of being stripped down so it had no bed and no front fenders or hood. It looked pretty cool like that :D . After awhile my buddy (in another truck) said my manifold was red. So I get out and sure enough there it was glowing brite red redface.gif :eek: I was so proud :D

[bvibert]

Originally posted by The Preacher:
</font><blockquote>quote:</font><hr />Originally posted by coolram:
Preacher the pump we are referring to is the Air Injection pump(A.I.R.).It takes exhaust gases from the exhaust manifolds(the air tubes connected to the manifolds and routed thru hoses,thru divertor valves)to oxygenate the cat convertor.That's what the small line to the convertor is for.That's why we use 3 way convertor.3 way converter?? Does this apply to a '77?

I have the tubes on my manifolds but I don't seem to have a separate line running to or from my cat.

Sorry, but I am still not all the way with you on this one.

This is important for me to get straight since I am running a cheater right now myself and my chero is running bad.</font>[/QUOTE]I don't think the older trucks had a line down to the cat.

By the way the air pump doesn't suck exhaust gases from the exhaust manifolds, it pumps fresh air into them and the cat on vehicles so equipped.

[jeepguzzi]

Be sure to also check your plug wires and timing. Cross firing plug wires or a mis-timed engine will fire the mixture a bit late, allowing it to heat things up too much.

[reddog]

Ditto the advice on checking the carb. A blown power valve dumped enough fuel through the exhaust on my 87 to burn through the exhaust manifold.

Kerry

[The Preacher]

[/qb][/QUOTE]I don't think the older trucks had a line down to the cat.

By the way the air pump doesn't suck exhaust gases from the exhaust manifolds, it pumps fresh air into them and the cat on vehicles so equipped.[/QB][/QUOTE]

In other words, does not apply to me.

Thanks for clearing that up!

Sorry for "jumping" this post.

[new2fsjeeps]

for what its worth the cat may be cloged. My baby wrangler did not pass emmisions(when we had the test.) we went looking for the problem and found all of the honeycomb stuffed up in the back ot the converter. I took it off used a piece of rebar to break it up and get it all out, went back to the place and pasted the test. Granted I know nothing about the systems on a FSJ as mine is disconected, but its amazing to me that thats what made me fail. an emmisions part, then pass with out it! hope this is atleast hurmorous if not helpful. the jeep was a tad louder but not by much!

[coolram]

The air pump does pull exhaust gas and mixes it with fresh air to supplement/oxygenate the convertor.If your rig uses air tubes it most likely had a 3 way(with air tube) cat convertor.