i have a diesel leak from one of the hard lines/hoses where it connects underneath the engine going up to the fuel bowl, i believe its a return because it doesnt draw air, and really only leaks worse when running. its the middle of the three line to hose connections under there. where can i get these lines? does the connection go bad at the hose or do i have to replace the whole line?

 

A coworker just had to replace one. His was the passenger side that ran to the rear of the head. The dealer was half price of the local parts shop.
Go here and pick the one you need.
http://images.search.yahoo.com/image...78HB&fr=iphone

 

The passenger side fuel line is common on 7.3's. They crack near the turbo because of a metal clip rubbing on the line. Riffraff diesel has them for 44.99.

 

do yourself a favor and replace them all. last spring i had to replace the line from pump to filter. in september i had to replace the lines from filter to heads.
if one is rubbing, the others are too and will soon fail.

 

Can I get to the lines behind the head? I will replace them all. Also I have an exhaust leak from what seems to be the manifold, but it's only under load. It's less when it's in neutral which leads me to believe it's an up pipe or something, anyone else have that problem?

 

Up pipe exhaust leaks are very common. Look at them, if you see soot... leak.