Rebuild by LS Newbie.
 

Hey guys, got another LS question. While tearing down the 5.3 that will reside in my C10 SWB clone. I noticed oil on a couple of the exhaust manifold bolts. One on each side. Are the bolt holes open to the oil channels? Do I need to be sure they are sealed properly when I reinstall the exhaust?

Re: Rebuild by LS Newbie.
 

I've pulled several sets of manifolds off and have never seen oil on the bolts ..

Re: Rebuild by LS Newbie.
 

Your valvecover gaskets are leaking, more than likely. Take a look at the heads and see if you can follow a discolored area back up to the valvecover or the bolts that hold it down. Nothing on the exhaust manifold bolts touches an oil passage.

Re: Rebuild by LS Newbie.
 

PO cleaned off the motor somewhat so it may of been that.