Diesel Tank Venting

[b. rock]

Had a strange occurrence on a steep off road uphill the past week. Diesel started spilling out what I assume is the vent (it was completely open to atmosphere, a long tube that ended at the end of the tank). The van stalled out and died and wouldn't run again until we let it sit for awhile on flat ground. I had gotten fuel about 18 miles prior so the tank was pretty full. My understanding is that the modern diesels recirculate back to the tank - so if the vent was plugged or wasn't able to breath properly it would start to pull a vacuum. The van has been through a 4x4 conversion and engine swap, including making the switch from gas to diesel, so there's been a lot of hands in here before mine.

Is there a proper way to vent a diesel tank? I need to rework it so it doesn't spill fuel on the ground at a minimum. Does my analysis also seem plausible as to what went on with the van?

Thanks

[JWA]

When you say "modern diesels vented to tank" what year is your van or to what year spec's was the gas>diesel swap were used?

[b. rock]

It was a 2006 V10. It now has a 6.7 Cummins in it, conversion done in 2013-2014. Advanced did the 4x4 conversion very early in its life, but the tag is worn enough that I can't get an exact date.