Bubbles in a fuel pro 382. Detroit 60 series

Prior to this getting worse, I was seeing a lot of bubbles in the filter housing.The next day, I couldnt crank it up.I tried with ether and still couldnt.Called a mobile service and was able to get me going with ether.
I got back home and changed the suction line that comes from the fuel separator to the fuel pump, and I also chnaged out the fuel filter.I am not seeing bubbles , but I am wondering if I have solved my problem.After the change, I drove around for an hr.Shut it off and cranked it back up and I am not seeing fuel in the glass.I am wondering if this fuel will rise up a little bit for the system to remain primed.I guess I wouldnt know until I crank it up tomorrow.I seriously doubt its the check valve , because that check valve at least waits a couple of hrs and you usually dont see bubbles in the glass.My question is, incase I loose my prime from the Davco in the morning, how will I diagnose this in finding the air leak/bad hose on the suction line?If this truck cranks in the morning then I know that short suction line that I changed(that line did looked frail) was bad.Someone mentioned pressurizing the fuel line to find the bad hose.Any ideas on how to do this?

 

It cranked right up.
problem fixed!!!

 

Yep, I just learned all this.Yes, I had a major bubble before all these changes.The suction line or the dome must have fixed the problem.Suction line, pressure line, fuel pressure in PSI, crossover T fitting,return lines and check valve...............................I learned a lot from this experience.The only thing I need to learn is how to pressurize the system to detect a bad suction line

 

Sorry, guys this problem has not been fixed as I thought.I noticed this 2 days after my last posting.I left it with the mechanic.It's still loosing it's prime in the Davco.Took it to the mech and he plugged his pro link.Injectors are fine from the scanner.From research, I was thinking vent tube but another mechanic said it shouldn't cause it to loose prime and not start.Mech. will update me in a couple of days.Not sure, it may even be injector O ring as another mech suggested.I have changed all the fuel lines except 2 suction lines on the seconday.I didnt see that much leak from those hoses.My mech. will keep me updated.

 

Yes, , my davco is empty in the morning.Hard to also start.I dont even know why one mech said check valve.I have never seen a check valve act up while idling.All my symptoms and what I have done is in this thread.............................hard to start in the morning, sometimes starving for fuel while idling but drives normal on the hwy