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Old 03-01-2011, 06:13 PM   #1
JustJeff
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Default Are these exhaust gaskets reusable?

I'm thinking engine to manifold gasket is good to go but I'm wondering about the manifold to turbo gasket?













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Old 03-01-2011, 07:49 PM   #2
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i would order a new set bro
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Old 03-01-2011, 08:58 PM   #3
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They do look rough. I would think you will have to over torque everything to get them to seal properly and the stock turbo mani is known for cracking.
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Old 03-01-2011, 11:31 PM   #4
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Look good to me...
I wouldn't hesitate to reuse them.

For the turbo -> engine, inspect the crimp edges around the exhaust port.
Make sure there are no cracks or creases running radially.
Look for signs of exhaust leaks - black marks that indicate exhaust gases are leaking past the gasket; it will look like a cone-shaped black mark most of the time.

For the turbo -> turbo exhaust manifold, basically the same thing/
No cracks...no creases.

Warped is okay, since it'll be clamped down during proper torquing of the fasteners.


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Old 03-02-2011, 12:41 AM   #5
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Quote:
Originally Posted by RETed View Post
Look good to me...
I wouldn't hesitate to reuse them.

For the turbo -> engine, inspect the crimp edges around the exhaust port.
Make sure there are no cracks or creases running radially.
Look for signs of exhaust leaks - black marks that indicate exhaust gases are leaking past the gasket; it will look like a cone-shaped black mark most of the time.

For the turbo -> turbo exhaust manifold, basically the same thing/
No cracks...no creases.

Warped is okay, since it'll be clamped down during proper torquing of the fasteners.


-Ted
Thanks Ted

All the crimped edges look great. No cracks, no creases. I am concerned about some darkness on the engine to manifold gasket and also one crack on the exhaust manifold.


Tomorrow I'll get some macro pics of the manifold crack. I'll post those in a new thread. It's getting close to extending beyond where the gasket starts sealing, but hasn't yet. I didn't have any problems with leaking while the car was a daily driver. I've got a second S5 manifold but it's in worse shape. Rather than spend on another 20yr old part I'd rather milk the life out of the one I have and use money later for an upgraded manifold.
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Old 03-06-2011, 03:50 PM   #6
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Turbo to downpipe gasket. I didn't store it properly and it got damaged. I'm thinking this isn't useable, but wanted some opinions.


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Old 03-07-2011, 10:28 AM   #7
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if the only damage are those scratches ^^^ then it should still flatten out and seal pretty well. I don't see any cracks.
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Old 03-07-2011, 10:55 AM   #8
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they all look fine. the downpipe gasket will flatten out when torqued down.
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Old 03-07-2011, 11:36 AM   #9
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No cracks, just the damaged area shown. Reusing saves me $70
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Old 03-07-2011, 11:48 AM   #10
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Quote:
Originally Posted by JustJeff View Post
No cracks, just the damaged area shown. Reusing saves me $70
more like $150 for all three!
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Old 03-07-2011, 12:32 PM   #11
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Quote:
Originally Posted by FerociousP View Post
more like $150 for all three!
All three are close to $200 through Atkins!!!
$85 for manifold to engine
$40 for manifold to turbo
$72.75 for turbo to downpipe

I've got a rebuild parts and price list I'm keeping for my budget.
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Old 03-07-2011, 12:51 PM   #12
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Quote:
Originally Posted by JustJeff View Post
Turbo to downpipe gasket. I didn't store it properly and it got damaged. I'm thinking this isn't useable, but wanted some opinions.



This might seal initially, but I think it's going to fail prematurely down the road...
This might be worth replacing at this point if you don't want to deal with it within a few months to about a year.

The problem with this kinda damage is that the metal gets work hardened and will never go back to it's original (or preferred) shape.
Since torque specs are not excessively high - I believe it's only like 30 lb-ft or close to that? - I doubt the fastener torque is enough to flatten it out totally.
It'll be a different story if you're able to re-anneal the metal, but I doubt that's possible in this case.

The problem with exhaust gas sealing gaskets is that if you give the exhaust gases just a tiny alternate path to escape, it will and will cause a bigger gap the more you run it.
The gasket needs to have a perfect seal before running it with any miles or else it'll fail prematurely.


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Old 03-07-2011, 02:44 PM   #13
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Quote:
Originally Posted by JustJeff View Post
All three are close to $200 through Atkins!!!
$85 for manifold to engine
$40 for manifold to turbo
$72.75 for turbo to downpipe

I've got a rebuild parts and price list I'm keeping for my budget.

you are right. I priced mine through pineapple and they are close to $200 after shipping. I bought the manifold and turbo gaskets through them, and reusing the DP gasket. If it leaks, at least it will be much easier to change than the other two and you have the chance to save some $$
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Old 03-07-2011, 05:34 PM   #14
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Quote:
Originally Posted by RETed View Post
This might seal initially, but I think it's going to fail prematurely down the road...
This might be worth replacing at this point if you don't want to deal with it within a few months to about a year.

The problem with this kinda damage is that the metal gets work hardened and will never go back to it's original (or preferred) shape.
Since torque specs are not excessively high - I believe it's only like 30 lb-ft or close to that? - I doubt the fastener torque is enough to flatten it out totally.
It'll be a different story if you're able to re-anneal the metal, but I doubt that's possible in this case.

The problem with exhaust gas sealing gaskets is that if you give the exhaust gases just a tiny alternate path to escape, it will and will cause a bigger gap the more you run it.
The gasket needs to have a perfect seal before running it with any miles or else it'll fail prematurely.


-Ted
What you said about once exhaust finds an alternative path and causing a bigger gap makes perfect sense. What do you think about pressing the gasket before I put it back on? Do you think putting higher pressure/torque on the gasket to "even out" the damage would work? Or is that going to simply exasperate the problems and accelerate the deterioration?

Quote:
Originally Posted by FerociousP View Post
you are right. I priced mine through pineapple and they are close to $200 after shipping. I bought the manifold and turbo gaskets through them, and reusing the DP gasket. If it leaks, at least it will be much easier to change than the other two and you have the chance to save some $$
That's what I'm thinking, put it on for now and defer some costs for later. Doing this rebuild in this economy is already bleeding me pretty dry. It's only $70, but nickle and dime stuff is killing me. Hell, putting that in perspective. If I save that much now that's 1/3 the cost difference between Atkins apex seals and OEM. I can always slap new gasket on later, cant' exactly do that with apex seals.
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