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DDlighttruck · 01-24-2018, **(Subject: Exhaust manifold )**

I have one broken exhaust manifold bolt, that in turn is causing a slight exhaust leak. Do I assume the manifold is warped, because the bolt is broken? Do I pull the manifold and check it with a straight edge and feeler gauges, but have a new one there just in case?

I have a feeling I know the answer to this, but I'm honestly curious: is there any gains to the aftermarket exhaust manifolds? The ported and coated ones. My boss said he'd give one a hard look if it was his truck.

Why do I get the feeling I'm going to get yelled at for asking that.....

Wiseman · 01-25-2018, **(Subject: Exhaust manifold )**

It’s been said before from the authority here :
You gain nothing, unless you’re pushing well over 700 HP .
In your case , Slight exhaust leak will be gone with new gaskets. Get a set of new bolts with the gaskets . They stretch. Use proper torque.

Signature620 · 01-25-2018, **(Subject: Exhaust manifold )**

Get a price to machine the manifold flat again. I see these engines with leaking manifold gaskets just weeks after a rebuild all the time.

Wiseman · 01-25-2018, **(Subject: Exhaust manifold )**

I totally agree with you! But the problem is the three pieces manifold. If it’s not jigged right when resurfaced can make it worse during expansion and contraction . What I mean is like when you try to press bushing or bearing and one side go first and doesn’t go even all around.
So it needs to be in the hands of machinist that really know what are the consequences.

Rawze · 01-25-2018, **(Subject: Exhaust manifold )**

The 3 pieces is to allow for heat expansion. If the manifold expansion joints are rusted together bad enough, it can also make for broken bolts. I think here is a kit or something to replace the expansion gaskets too. Not sure what is needed to do this job though.

Wiseman · 01-25-2018, **(Subject: Exhaust manifold )**

(01-25-2018 )Rawze Wrote: The 3 pieces is to allow for heat expansion. If the manifold expansion joints are rusted together bad enough, it can also make for broken bolts. I think here is a kit or something to replace the expansion gaskets too. Not sure what is needed to do this job though.

I’ve pulled mine a part before and didn’t see anything that resembles gasket in the joints. Was scratching and wondering how to hell this thing seals?
I guess is only tight tolerance. Never noticed any signs of exhaust leak from them.
You make me scratch again.

Signature620 · 01-25-2018, **(Subject: Exhaust manifold )**

They have thin steel rings that you tap on with a Cummins tool and a hammer.

JMBT · 01-25-2018, **(Subject: Exhaust manifold )**

Signature620 is right!! There is a gasket or “sealing ring” made of thin metal. And...they are a pain in the ass to get apart after the manifold has been in use for awhile. If I remember right, I greased the new sealing rings before pounding them on. But that was a few years ago!

Wiseman · 01-26-2018, **(Subject: Exhaust manifold )**

(01-25-2018 )Signature620 Wrote: They have thin steel rings that you tap on with a Cummins tool and a hammer.

A picture by any chance!?