Exhaust Manifold Resurfacing?

[welch_41]

Guys, I need some help. I'm restoring a 66 C10 with a 250 and it's my first build. I'm learning as I go so bare with me if this is a dumb question. My exhaust manifold is pitted and needs to be resurfaced. My question is do I need to send in both the intake and exhaust manifolds to be resurfaced so that after they are bolted back together they will sit flush against the head? Or, do I only send in the pitted exhaust manifold for a shave and the tiny gap created between the exhaust manifold and head, because the intake is a little longer, will have no negative affect?
My gears are grinding in my head because I can't seem to find any answers for this...whats the use of google when it can't answer everything. Thanks for any help!

[ol Curt]

All three will give a nice flush fit, but I just did the intake and head.

[protrash64]

I think I would send/take both and ask the machinist. Do they both use gaskets that are similar or that change the gap? You definitely dont want the intake leaking.

[welch_41]

They both use the same gasket. A buddy of mine along with ol Curt both said the same thing. I think I'm more worried about too much being shaved off and the gasket not sealing properly.

[protrash64]

Im not that familiar with the 6's. I know the intake and exhaust fit together. Have you thrown a staight edge on the parts just to eyeball it? Maybe some sealer on the exhaust would do the trick.

If the parts arent warped, I wouldnt machine them unless the pitting is bad.

[welch_41]

I tried adding filler a while back but it didn't do any good. The paste didn't hold and ended up blowing out. I only have a pitting problem with the 6th/rear cylinder but other than that it's pretty flush/straight.

[joe231]

back when I was a mechanic for a living, after resurfacing, we would use anti-seize (sans gasket) it is high temp and fills in any perfections. I realize it may sound crazy, but it works!
dunno for sure about you six, but on a ford I-6 we would send the intake and exhaust out together to get resurfaced....

[welch_41]

I never thought about putting anti-seize on an exhaust leak...what would keep the pressure from blowing it out? Fixing this exhaust leak is the last thing I need to do before the engine is back to purrring. I traded my motorcycle for this truck....then realized how much work it needed. Totally worth it!

[welch_41]

The machine shop said to bring in both since they bolt together. Same price which makes it even better. Thanks for the help guys.

[joe231]

Originally Posted by welch_41

I never thought about putting anti-seize on an exhaust leak...what would keep the pressure from blowing it out? Fixing this exhaust leak is the last thing I need to do before the engine is back to purrring. I traded my motorcycle for this truck....then realized how much work it needed. Totally worth it!

the anti-seize compresses and fills in any minor imperfections.

[protrash64]

Right on Joe.......my 90SS454 had a rebuilt engine and thats what they used on the manifolds. I didnt know what it was, thought it was just a regular type sealer.

[TimE]

Didn't know that. I'll have to store that in the old data bank for future reference.