What is the oil line that runs from the oil filler tube to the crankcase? Would it be possible to tap into that for the breather tube rerouting.

 

Just a vent line.

 

That is the return line. Not sure what you mean by tapping into that line for "breather tube rerouting" but, even so, doesn't sound like a good idea.

 

Let's have some feedback here. I'm under the impression that's a vent line. The oil pump has a feed and scavange function that works out the rear of the cam cover with a feed and return line. If the vent was a return line, the camcase would be full of oil with no pressure to evacuate the camchest. If this is correct, the OP is suggesting venting the rocker boxes to this line instead of routing to the air cleaner, which sounds plausable to me.

 

Venting the breathers back into the engine crankcase, even if it is a oil return line or whatever, makes no sense. After all, the breather vents are the vents for the crankcase also. You would in effect not be venting at all. In addition, any oil return line is going to be pressurized so breathing won't occur, only oil being forced outward. The EPA regs mandate the breather lines be vented into the air cleaner so the fumes can be sucked back into the engine and burned with the combustion. The old days of straight venting to the atmosphere are gone. At least from a manufacturing standpoint.