Very very very slow filling gas tank

2012 was the year I believe. There are actually multiple float valves on top of the tank. There’s the regular inlet valve, usually on the tank, but sometimes it’s an inline valve in the fill neck. The inlet is typically near the front of the tank if packaging allows. Then in other places on the tank there’s the vent valve (middle) and a grade valve (rear) that acts as a backup vent valve for if the boat has a different attitude. The air side of the grade and vent valves are hooked together, so they serve the exact same purpose. On carbon canister systems, the air side of these valves are plumbed separately from the inlet. But on pressurized systems, they are plumbed back into the fill neck assembly.

When liquid fuel fills up to the bottom of a float valve, it shuts off the vent to the air side. Automatic shutoff fuel nozzles will trip when either of these two occur:

1. The float valve on the inlet closes (or the inline flapper closes).

2. Both the vent and grade valves close, not letting any air escape the tank.

 

A lot of good info and cross-talk everybody, thanks.

 

I wondered why my Pro V has 2 vent lines one in the front of the tank and one in the rear. I now know

 

I doubt the carbon canister is the problem. It’s probably one of the float valves.

 

Because boats use the same carbon canisters that have been on all our cars for decades and they very rarely cause problems.

 

If you store your boat in a garage with the canister removed, your garage will start smelling like there’s a can of gasoline in there with the cap off.

 

If the vent and carbon can is clear, Make sure your vent hose is above your fill hose and doesn’t have any dips in it. Also make sure the fill doesn’t have any dips it it. A dip can create a pocket where fuel will sit and cause enough back pressure to stop the pump. You want a nice smooth line for fuel to run, preferably down hill. Also there should be a check valve in the fill hose. Might be getting tight and causing too much back pressure. Most are plastic and some plastic will swell or warp in fuel over time. Specially ethanol fuel.


Sent from my iPhone using Michigan Sportsman mobile app

 

Had this problem of the pump shutting off constantly. I fund by rotating the pump handle to the one o'clock position while filling allowed the fuel to run down the neck unobstructed. You'll need to find the sweet spot and remember it every time you fill up. And don't shove the pump all the way in so it allows air to vent out, releasing pressure. My 2019 Adventure did the same thing

 

Interesting reading.my new boat arrived
at the dealer from Lund just prior to the stay at home order. I’ll remember the advise given if I have the same problem whenever
I finally get the boat home.