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Catalytic Converter Rear Flange - 99 OWB

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While out of the country recently I got the news that the exhaust had fallen off of the outback. I'd bought an aftermarket midpipe before leaving for Sweden as I knew the midpipe was in sad shape, but I hadn't had a chance to put on yet.

 

Upon inspecting the damage I found the midpipe was broken in half, not a surprise, but I also found that the flange on the rear of the cat was completely gone. The cat itself is in good shape, so I hate to replace it ($$$$), but I can't mount the replacement midpipe as it is.

 

The front of the midpipe has what looks like the socket part of a ball and socket flex joint. I would like to find the matching flange to weld to the cat. Normally I would just weld the pipe to the cat but like I said it looks like a flex joint.

 

Any ideas, pics, suggestions that may help me in my quest are greatly appreciated.

When the cat pipes have been welded in the past, they dont seem to hold up. But maybe you can go to a junkyard and cut off the flange, then match it up to yours and weld it on.

 

nipper

Any ideas, pics, suggestions that may help me in my quest are greatly appreciated.
Well not sure if these pics will help but here they are:

exhaustleak00obw-2.jpg

exhaustgasket00-2.jpg

I used a split flange on my 97 OBW on the rear of the cat. The ears from the heat shield are still there and help to hold it on, then with longer bolts and the gasket, it's sealed. Been holding for a few months now...

I'd think maybe a muffler shop would have the other side of that donut flange, and then you could get it welded in place so it will bolt together. I'm currently trying to figure out where to get one.

 

I'll be getting a new exhaust soon and I plan to have a donut gasket flange and extension installed on an e-bay header so it will bolt up to a wrx midpipe.

I had the same thing happen last year. I even went and pulled one from a yard, and as soon as I got it off and cleaned away the gasket, I found that it was heavily rusted and ready to break. I just went to a local independant exhaust shop and got a flange and welded it on to my original cat my self. The flange I got was about twice the thickness of the original flange, but everything worked out.

 

Keith

  • Author

Thanks to everyone for the help.

 

porcupine73: That gasket looks just like the one that came with the midpipe. I assume that the rounded end goes toward the rounded flange on the midpipe. Thanks for the pics.

 

RallyKeith: Thanks, very good info. Can you describe in detail the flange that you welded? Was it just flat with an appropriately sized center hole and appropriately spaced mounting bolt holes?

 

It looks like I'll have to throw the plates back on the ULSD-leaking TD Jetta and run around looking for this flange today. The suby is WAY too loud to drive.

 

I'll take the cat off and take it to work and weld it with the MIG.

 

Thanks again,

 

:cool:

Thanks to everyone for the help.

 

porcupine73: That gasket looks just like the one that came with the midpipe. I assume that the rounded end goes toward the rounded flange on the midpipe. Thanks for the pics.

 

RallyKeith: Thanks, very good info. Can you describe in detail the flange that you welded? Was it just flat with an appropriately sized center hole and appropriately spaced mounting bolt holes?

 

It looks like I'll have to throw the plates back on the ULSD-leaking TD Jetta and run around looking for this flange today. The suby is WAY too loud to drive.

 

I'll take the cat off and take it to work and weld it with the MIG.

 

Thanks again,

 

:cool:

 

Sorry, I've been dead to the world the past day. The flange was just like you described. The hole in the center was the correct size, and the bolt holes were actually slotted to fit multiple applications. The hardest part is welding it since the wall of the pipe is thin compared to the thickness of the flange itself.

 

Good luck.

 

Keith

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