Exhaust sealing ring

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redcar
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Post Fri Apr 19, 2013 8:44 pm

Hi guys, just need some advice regarding the following;

Image

How does that actually seal the exhaust gases? As when I tighten the two flanges against each other, the downpipe can still move in and out of the exhaust centre section.
Is it worth buying a new sealing ring or will the original ones I have be fine.

Also, I barely even tightened the flanges together when the downpipe side flange snapped in half. You can see this in the following picture. Please could someone tell me the part number for the flange so I could get a new one. I suppose it's BMW only for this part?

Image

And last one, in the following picture, is what I'm doing for the second downpipe correct? Is it the smaller inner diameter sealing ring I should be using for this downpipe?

Image

Thanks in advance.
Rtaylor2208
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Post Fri Apr 19, 2013 10:31 pm

The gasket rings are dealer only and compresse when fitted. When fitting them use some exhaust paste or even gum gum on the joints and they'll be a good tight seal.

Had the same Issue with mine last year when replacing the back box on my cab.
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redcar
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Post Fri Apr 19, 2013 10:34 pm

Rtaylor2208 wrote:The gasket rings are dealer only and compresse when fitted. When fitting them use some exhaust paste or even gum gum on the joints and they'll be a good tight seal.

Had the same Issue with mine last year when replacing the back box on my cab.
i thought that they would compress as well. However, like I said earlier, the downpipe could still move in and out of the centre section. Therefore I assume that it wasn't compressing and clamping on the downpipe. Also, I might have the wrong part as mine is a thick, solid metal ring so I can't see how it would ever compress or deform. :(
Rtaylor2208
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Post Fri Apr 19, 2013 11:19 pm

The two I got were made from metal as well. I can't remember which way round they went but on is thicker and goes within one pipe and one is thinner and goes on the outside of the other.

I will hopefully be putting my exhaust back together again tomorrow as its off for some prop work so I can check which way is which tomorrow.
Rtaylor2208
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Post Fri Apr 19, 2013 11:20 pm

Actually is yours a 2 or 3 piece system? Mine is a 2 piece.
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redcar
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Post Fri Apr 19, 2013 11:23 pm

Mine is 3 piece. :)