my bets on the fuel bowl drain valve.
Most of us have been thru this before,It's either o rings,hoses,or fuel pump.Sounds to me with engine running and system under pressure the pump is leaking ,unfortunately for me I too am having pump leaking but not as severe as yours.The valley becomes saturated with fuel and then drains down back of engine.There is a pressure switch on th FPR that will leak,but you can see easy enough.If you have a asphalt driveway,the diesel will eat it up,I know from my last PSD.
The first post above is good advice or info as to what to expect. I would however suggest just buying all new hose, Orings and fuel pump and possibly sensor too. It is too much work to get in there and not it all done.Does anybody have a step by step for pulling the fuel pump out or of at least how to get in there and tighten down all the connections? I am having pretty much the same issue. Fuel collecting in the valley on both sides of the fuel filter housing and dripping down the back of the engine over the transmission cover, bell housing, and starter motor.
