[Engine] Dw8 leakoff pipes

[Lucas87]

Hey guys my injector leak off pipes have been disconnection  since I got the car so yesterday I replaced all the hoses with new and refitted the feed pipe to the top of the full filter came to it this morning and it wouldn't start and was full of air so disconnected the feed pipe and blanked and fired up and ran fine all day any ideas as I'm stumped as I've replaced all the hoses with new .?

[brodfather11]

if the leak off pipes were disconnected then there would have been diesel all over the engine ?

If not then it was something else you connected

[Lucas87]

if the leak off pipes were disconnected then there would have been diesel all over the engine ?

If not then it was something else you connected

Sorry should have been more specific the leak off pipes between injectors where all connected but the pipe that comes off the top of the filter lid has been blanked off and the little spout on the lid its self has also been blanked I've put all new leak off pipes between injectors and replaced the pipe that goes to the filter lid with all new. It runs fine with the pipe and feed blanked but as soon as you connect it by morning air has gotten in to the system 

[brodfather11]

if that pipe is not airtight then overnight all the fuel will run back to the tank . The high pressure pump sucks the fuel from the tank through the fuel filter and relies on airtight joints.
Air can leak into the filter through a bad seal round the top of the filter. I've seen the little pipe stub on the lid cracked at the base..
Something is letting air in when that pipe is not blanked off.