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Discussion Starter #1
Hi, I had removed my intake/exhaust for access reasons to do some other work and noticed the front and back exhaust (1 & 4?) gasket looks wonky. It doesn’t seem broken through, just like it has eroded on the outside edges.

The head looks like in that area but had the obvious witness marks of blow by, which was easily wiped off. The exhaust flange has not obvious defect but i havent checked flatness yet. Is this an exhaust manifold distortion issue? Or something else?

Obviously I am going to replace the gasket, anything else I should be checking or changing?

Thanks for your help.
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It was definitely leaking. It is fairly common. You need to make sure that you retorque the exhaust studs a few times after running the engine, IME.

Make sure you use a Reinz or Elring gasket.
 

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it was indeed leaking as Johnny said.
We have them milled to make them flat.
Yours has warped and will leak again if it is not machined.
Tightening it up when warped can crack or break the manifold which is also a common problem.
Since the head is aluminum and the exhaust manifold is cast iron the dissimilar metals have a different coefficient of expansion which will cause the torque of the exhaust fasteners to loosen over time.
You should check your manifold fasteners regularly and tighten accordingly to combat the thermodynamics at work to make things loosen.
 

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Discussion Starter #4
Thanks guys for the input. I will take a look locally for a machine shop to take a skim on the head. In your experience is it worth checking the exhaust manifold as well? Or do those break not bend?
 

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You have misunderstood the advice.
It's typically not the side of the head where the manifolds attach that needs to be machined, but the mating surface of the exhaust manifold where it bolts to the head.
 

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Discussion Starter #6
You have misunderstood the advice.
It's typically not the side of the head where the manifolds attach that needs to be machined, but the mating surface of the exhaust manifold where it bolts to the head.
I’m slow... sorry guys. :unsure:

You are suggesting machining the exhaust manifold flat? Leaving the head alone?
 

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Check to see if anything is warped first. It could have been loose bolts.
 
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