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Exhaust flange blew out again this morning

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Ok, so these things are supposed to slip on & off the pipes easily - sounds like mine is right. So it is a compression fit - now I wonder if the auto parts place is giving me the right gaskets.
They do slip on the pipes, not tight but not loose either.
I probably just didn't get the one of them on there square.
Thanks.
 
RickB said:
Ok, so these things are supposed to slip on & off the pipes easily - sounds like mine is right. So it is a compression fit - now I wonder if the auto parts place is giving me the right gaskets.
They do slip on the pipes, not tight but not loose either.
I probably just didn't get the one of them on there square.
Thanks.
Click to expand...

There's a flare that's been welded up near the end of each pipe AFTER the flanges are put on. This flare keeps the flanges from coming off. The donut gasket goes on the end and down against this flare.

In answer to your question - yes - you could consider this a compression fitting.
 
I'm sorry, but I don't think I completely understand this part:

<div class="ubbcode-block"><div class="ubbcode-header">Quote:] This flare keeps the flanges from coming off[/QUOTE]


Do you mean the ring around the pipe that the gasket seats up against when you put it on?

Do you mean: "This flare keeps the flange gaskets from coming off"?
 
RickB said:
I'm sorry, but I don't think I completely understand this part:

<div class="ubbcode-block"><div class="ubbcode-header">Quote:] This flare keeps the flanges from coming off
Click to expand...


Do you mean the ring around the pipe that the gasket seats up against when you put it on?

Do you mean: "This flare keeps the flange gaskets from coming off"? [/QUOTE]

No, this flare keeps the FLANGE from coming off the pipe. The flare is what the flange pushes against as the pipe assembly is drawn up to the manifold. The donut gasket is in between. It's really similar to a drain pipe assembly under your kitchen sink.
 
Ok, if the flange is the triangular piece that is loose and the bolts go through it to tighten it up to the bottom of the manifold then mine slips right over the flare with no trouble.
I don't see how it can push against the flare if it slides right over it with zero resistance. Is mine worn out or something? Is there a picture of this somewhere?
 
RickB said:
Ok, if the flange is the triangular piece that is loose and the bolts go through it to tighten it up to the bottom of the manifold then mine slips right over the flare with no trouble.
I don't see how it can push against the flare if it slides right over it with zero resistance. Is mine worn out or something? Is there a picture of this somewhere?
Click to expand...

If you can remove your flanges from the pipe assembly, something isn't right.

And I'm sorry - but I gotta run. Have an important meeting to go to and won't be back til Monday. Good luck.
 
Thanks Tom, I'm sure someone else here will help.
That's what's great about this place /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
Tom is right. The flange (triangular bit with 3 bolt holes) should not be able to come off the pipe. The pipe should have a collar welded to it that makes a cup shape for the gasket to fit into. That collar is larger in diameter than the flange hole, such that the flange will pull the pipe and gasket assembly up to the manifold. If you can pull the flange off of the pipe, then likely the pipe has lost its welded-on collar. You then need a new pipe. BTW... keep the flanges from the old pipe. Sprite guys pay BIG money for them.

Peter C.
 
Very interesting.
Guess I need to find another downpipe...

Oh wait, I think I hear the quiet whispering voice of someone in Georgia... No wait - that was Alabama!
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:] keep the flanges from the old pipe. Sprite guys pay BIG money for them[/QUOTE]

Ok, where are these Sprite guys...
Wait, I think I know some of them!

Why do they like old MGB flanges anyway?
 
The flanges are captive on the B pipe. They are the same as what 68 on 1275 Sprites use. Way better than the earlier Sprite set-up with the 2 piece clamshell clamp business. So, Sprite guys in the know will find the later manifold. The flange does not come with the Sprite pipe (it can slide on from the other end) and no one really catalogs the flange, yet every MGB guy throws 2 away when they do exhaust work.

Peter C.
 
I see, makes sense now.
Thanks!
 
Although I've only ever fitted a few, I've heard that the donuts are a-symmetrical (they only go on one way - they have a top and a bottom). I just fit mine however they seemed to want to go and they're fine. Others more knowing will no doubt chime in.
 
Well that's interesting.
I didn't see any difference from one side of the donut to the other.
 
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