fuel vent overflow

[BB marine]

you consider the geometry of the tank it is more effective/easier to have someone sit/stand on the port rail than on the bow. That doesn't completely eliminate the air pocket but reduces it dramatically. I also stand as far as possible to port when filling on the water. When on the trailer the issue is self correcting when hitched and is easily corrected by lowering the tongue when unhitched.

You are right on! A port list and bow down helps with the issue.

 

[Brunski]

I believe the Grade Valve mentioned above is only on gasoline powered vessels, not diesel.

In that case, adding a simple vent port teed to the existing vent should suffice.

 

[NorthernFocus]

...In that case, adding a simple vent port teed to the existing vent should suffice.

I guess I'm missing something here. How is a vent off the vent going to prevent burping out foam? Teed in where?