Blown exhaust gasket

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sideout
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Blew the exhaust gasket on my Avanti last night :cry: 'kin noisy and racing engine time. Nursed it home keeping an eye on CHT and EGT gauges. This is what I found....

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Do I replace it with a similar one, or could someone suggest an alternative?
Adam_Winstone
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The common copper + gasket material big bore exhaust gaskets, as supplied by many outlets, can be used and is unlikey to fail in such a manner. I've had similar failures with other gasket material exhaust gaskets once they've 'cooked' themselves brittle and then blow out.

Some people will suggest the solid copper type but I've never had much luck with them long-term.

Adam
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Muttley McLadd
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That looks familiar. Aren't they a consumable, to be changed every thousand miles?
CakeAndArseParty
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jason frost
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I fit these all the time, the thing to check is that the u-bend flange is flat, they are only thin and bend.
soosh
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I've blown this type of gasket too,I've reverted back to the copper type and have had no trouble.
Grumpy225
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Every exhaust I've set up I've surfaced the flange or at least checked before installed.


https://www.youtube.com/watch?v=_o59kYl8DoI

Once the exhaust has been used the flange will bend. It's a flawed design, really should have 3 or 4 mounting points (MDB RT style)
soosh
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Grumpy225 wrote:Every exhaust I've set up I've surfaced the flange or at least checked before installed.


https://www.youtube.com/watch?v=_o59kYl8DoI

Once the exhaust has been used the flange will bend. It's a flawed design, really should have 3 or 4 mounting points (MDB RT style)
But ok with the copper type though,can see what your saying and maybe this type of gasket needs that but not had issues. with the normal type.
Donnie
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I've always used the copper type and never had a problem, the composite only ones will always eventually blow.
Donnie.
gaz_powell
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copper sandwich type for me all the time
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sideout
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Thanks for the replies chaps, much appreciated as usual!

I spend ages flatting the flange to ensure is sits correctly with no high spots, but as Grumpy quite rightly says once it's been heated up a few times and the welding stresses are relieved it's going to move!

I think I'm off to the garage for a copper sandwich then Gaz :)
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