Fuel discharging from vents while fueling

[sailorbob]

No matter how slowly and carefully I pump diesel fuel, it seems that fuel comes out of the two vents on the transom well before the tank is full. Has anyone else experienced this and come up with a solution?

Second Wind #301

[KenKrawford]

Bob,
I know this sounds crazy but are you sure that your tank isn't full when fuel comes out the vents? Next time you fill up, write down the reading from the hour meter. The 350 should consume approximately 1.2 gallons/hour. Multiply the number of hours since your last fill up by 1.2 and that should give you the amount of fuel required to fill the tank.
Other than that, I'm at a loss.

[R.B.]

Also check to make sure the vent lines are not drooping. So that during a sail, the fuel can't slosh up the lines and not return back to the tank. If diesel stays in the lines, then as you pump fuel into the tank, the air pressure in the tank will push the diesel that is sitting in the lines out of the vents.