Fuel Tank Fill&Vent

[SlipperyOar]

I've got a 15 gallon in floor fuel tank for my 18' aluminum boat and i am redoing the fuel lines. Previously it had one line from the fill cap to the fill port on the tank, one line from the vent out the side of the hull to the vent port on tank, and the fuel to motor port. Would this Perko fuel fill and vent cap work to vent my tank all the time or is it just intended to vent while filling. I wasn't sure if the cap being closed seals off any air in/out through the vent line.

 

[dingbat]

I've got a 15 gallon in floor fuel tank for my 18' aluminum boat and i am redoing the fuel lines. Previously it had one line from the fill cap to the fill port on the tank, one line from the vent out the side of the hull to the vent port on tank, and the fuel to motor port. Would this Perko fuel fill and vent cap work to vent my tank all the time or is it just intended to vent while filling. I wasn't sure if the cap being closed seals off any air in/out through the vent line.View attachment 403735

The tank vent is built into the cap

 

[SlipperyOar]

The tank vent is built into the cap

I was somewhat unclear with my post, will this fill/vent component vent the tank with the cap closed or do i need another separate vent fitting through the hull as well?

 

[dingbat]

I was somewhat unclear with my post, will this fill/vent component vent the tank with the cap closed or do i need another separate vent fitting through the hull as well?

Not unclear…I have a vented cap as well. No other vent required

 

[SlipperyOar]

Not unclear…I have a vented cap as well. No other vent required

ok thank you for the quick & helpful response, its apprciated!