What can I use to replace rusted/broken flanges on exhaust pipes?

[TGreene]

I have a 1989 535i.

This is a diagram of the rear section of the exhaust:

http://www.realoem.com/bmw/showparts...71&hg=18&fg=20

Part #4 has the bolts rusted into it. There is one flange per pipe, and two bolts per flange. I can only use one bolt per flange though, so my exhaust is kind of loose.

I would have to cut the flanges to get them off, as the pipes are lipped and the flanges cannot be removed without breaking them.

Does anyone know of any product or part I could use that would let me cut off the flanges w/ the rusted bolts stuck in them, and replace them with something that would hold the pipes together properly, and it not be a hack job?

Thanks a bunch

[bmwdirtracer]

Why not concentrate on removing and replacing the bolts, instead of the flange? PB Blaster, and a BFH (big fkg hammer) should do it.

[TGreene]

One of the bolt heads is sheared off, and the other is very solidly in there. I had the whole exhaust out, and was working on getting them loose with fire, PB blaster, and a good deal of my weight leaning into it. Either it all comes off, or it all stays on. I don't have the tools to drill out, and I don't want to pay a shop to do it.

There must be some kind of part that I can use instead of these old rusted flanges.

[urotech]

oxy torch get em red hot!! and turn the bolts slowly. map gas also works but takes longer. I always use heat drilling these out suck

[TGreene]

There has to be something I can use - I just want to saw them off and put something nice and clean on - I am day dreaming about a flanges that clamp over the pipes, then can be used in the same way.

[bmwdirtracer]

You could cut off the bell on the end of the pipe, and weld on a new one, precisely. Or you could cut off both bells, and weld in a piece of pipe, which will be forever. Or you could buy a new flange-fitting from Summit racing, and cut off both bells, and weld the kit in. Or you could sleeve the exhaust pipe after cutting off the bells, then use a Dynatech (Summit Racing) band clamp with lots of antiseize, which never works for future removal either. Or, well you get the idea, it's only an exhaust pipe.Personally, I'd get the bolt out, whatever it takes.

[Haulin]

don't know if this will help but one way I have gotten exhaust bolts off when they are broken (if there are some threads still left) is get two nuts and tighten them against each other on the broken exhaust bolt then use two box end wrenches (one for each bolt) and turn them both as one in the loosening direction lefty loosy. It works.