It’s always out of the main fill. I once filled it up on a trailer at a petrol station and it was like you described - clicked off a bit early. But the 5 times I have filled it on the water at a dock (3 different docks) it has spilled out at the end. Wonder if it is a difference in how the auto shutoff things work, or simply the boat rocking, or maybe gravity (the boat in water sits a lot lower than the pump, whereas on my trailer it was really high?)
That still sounds a bit odd to me based on the different fueling issues people have reported here in the past.
So to be sure we are on the same page;
1-when you fill the boat up the fuel goes in without the handle clicking off all the way until full?
2- when you fill the boat up does the fuel handle click off unless you fill it at a reduced pace?
3-Does the fuel splash out just as the handle clicks off, or is there a pause after handle clicks off before the fuel comes out?
4-Are you the one filling the boat each time or is it another person?
5-Has the person filling the tank tried to get as much fuel as possible in the tank? What we yanks call topping off.
On your connext screen, on one of the pages there is a fuel used read out, on every boat that I have read about his fuel used indicator is very accurate, in my case to one tenth 1/10th of a gallon, .38 liters. This what I use to know how much fuel should go into the tank. There has been several people, mainly those with the 40 gallon / 151.4 liters who have had issues with their main graphical fuel gauge not coming off full evenly, jumping down to half or 3/4 of a tank from full as the fuel level is drawn down. Perhaps you can reset this fuel used metering tab after a full fill up and then check this readout before getting fuel so you will know when the tank is nearing full to help prevent spillage.
In reference to the questions I asked above, to me, it sounds like there is trapped air in the tank, and when the tank gets full, the tank burps out this air and in the process pushes some fuel out with it. This also makes me think that there could be a venting issue, the fuel tank vent flows through a carbon canister, and topping off the tank can put liquid fuel into this canister effectively either blocking the vent or dramatically reducing the flow through it, or in a few cases this canister somehow filled with water. This is where most people have had their fueling issues, but, in those cases the fuel was very hard to get into the tank at anything above a snails pace.
In the main fuel fill line is small spring loaded flapper valve that is inserted in the fuel fill line just above the fuel tank itself. The purpose of this flapper valve is to ensure that all vapors coming out of the tank as it fills passes through the carbon canister to capture the majority of those vapors for emissions reasons. In several cases this flapper valve has gotten turned sideways causing very restrictive fuel filling.
I hope that something I’ve written above will help you trace down why this is happening to you.
