Vito 638 Air in diesel line

[Deliguy]

Hi folks
I'm struggling with air in the diesel line. I've already changed the fuel filter, middle pipe fromthe filter to the pump and the two o-rings on the pressure regulator. It ran clear for several days of sitting on the drive testing it but within 4 miles of the test drive air bubbles were appearing again. I managed to get her back before she conked out, took it all apart again, put it back together, bled the air out of the system for it to be clear again but air keeps creeping back in, now within a few minutes of it just sitting on the drive. The fuel filter is the type without the water separator so that rules that out.
What have I missed? Any more suggestions?
Jamie

 

[Deliguy]

Weird right?

So look - I can run it and get the line clear again:




And it's been ticking over fine for 20 minutes now but as soon as I drive it for a few minutes the bubbles are back.
There's no wetness on the belts and there's no drips underneath.

Any suggestions?

 

[Deliguy]

Videos uploaded

Although you've all seen it before I guess!

https://youtu.be/hCVy8f6W9AI

https://youtu.be/CB0c0H7bzXo

 

[Deliguy]

Fixed? Air in the Diesel lines

Ok, ran her out for twenty miles today, no air bubbles in the hoses. Even hit some potholes. Dare I hope that it's fixed? I'm wondering if it could have maybe just been air in the back of the system that I just needed to work out, let it stall, fill it up and work it out again?

 

[Deliguy]

Have run her for 125 miles now with no more re-occurrence. Safe to say it's fixed? I'll let you know if it's not!