C220cdi w203 Air in fuel pipe

[mikezxcv]

I have recently replaced a fuel line on my 2003 c220 cdi due to air getting into the system. Does anybody on here Know how to use the bleed valve on top of the engine to remove air from the system. As I have flattened my battery with the starting problem of air getting into the system the battery is no longer good enough to turn the engine over long enough to pull the fuel through. the bleed valve i am talking about is part of thee fuel line that i replaced. Thanks