diesel 6.5l help

[picc53]

i have a 95 chevy k2500 6.5l just replaced the lines on the return and put in new lift pump started up and checked the bleeder on top of fuel filter fuel pouring out then drove around for little while and came back to check the bleeder to see if fuel was coming up but nothing truck dies out shortly after it idles for hours but sometimes up hills it bucks and has a lack of power

we bypassed the ops with a toggle switch that runs of the lift pump to the fuse and as soon as we changed the pump and wired it we had fuel but now after driving for little while and checking bleeder again nothing what could it be

[More Power]

Is the lift pump actually generating fuel pressure when the engine is idling? Sounds like it was then isn't....

Using an OPS powered lift pump is a safety issue. If an accident occurs, fuel won't as likely be poured onto an already bad situation.

Jim