Disassembling a very Rusty intake to clean manifold

I would especially after a head resurface reduces the size of chain required. Your old chain is already stretched.

 

Generally my heads come back in a plastic bag that has like the smell of marvel mystery oil in said plastic bag. In the head if I put it next to a brand new one from Toyota is almost identical It's been tanked cleaned valves ground all the nastiness on the back side of the valves looks brand new It's all been cleaned up removed ground lapped whatever so there's always that now if they don't do the valves then of course the oil well on top of the head where you're pouring the oil through your valve cover that may get tanked and cleaned but it won't look like new per se it'll be pretty close everything on your head looks like it's supposed to.

 

Don't worry about that exhaust manifold it all just run a wire wheel over it or your wire brush You got a gasket that's going on there No problem this is what they all look like doesn't do any good to jet coat them or anything like that It's all hidden away in the back nobody's really looking at it It's a reasonably well made exhaust manifold too so everything is good You can do all that stuff to it but it's just paying for something you can't really see.

 

I would concentrate on the intake manifold if you are not replacing it followed by ensuring you can see light through each of the egr cooler channels.

Cooler part
25601-37010

 

With the exhaust manifold flange I think the only crucial zones are the raised rings around each exhaust passage, and maybe the similar zone at each bolt hole. The remainder is rough casting, slightly recessed.