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Sweetwater 220 Fuel Vent Issue

I'm looking for some advice regarding what appears to be fuel vent issues. 2012 Godfrey Sweetwater 220 Pontoon. After about an hour or so the Honda 90hp vtec just dies like its out of gas. We have found that when we loosen the gas cap an excess amount of air pressure comes out then the engine will start and run fine for about another hour or so. The vent runs directly beside the filler mounted to the side of the boat. I can't find any low places or obstructions on the vent hose. Any advice greatly appreciated!
Also looking for a Ski Rope Tow Bar.
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I have the exact same problem with a 2016 18' Sweetwater and 40 HP Honda. I contacted Godfrey and they sent me a diagram of the fuel system but no advice. When it happens and I crack my gas cap it sounds like an inhale rather than exhale. I think the Net Positive Suction Head drops to a level where we get vapor lock but thinking this does not solve the problem. After you look at the fuel system diagram IMHO I think the government has made such demands on escaping vapors it is impossible to have the problem solved.
Missed Again
Has anyone figured out this system and solved the problem? Thanks, Dean
OK, where to begin (I apologize cause this will probably be a bit long and more info than you wanted), the fuel problems exists with any boat manufactured from 2011 to 2019 and it has to do with new EPA mandates (our government at work) on marine fuel tanks and how they now have to not allow hydrocarbons into the air. Boat manufacturers purchase fuel systems from fuel system manufacturers that offer approved fuel storage systems. These manufacturers designed the EPA compliant fuel systems for boat manufacturers to use on their boats. Prior to 2011, fuel systems were vented at the or near the cap, allowing hydrocarbons (gas fumes) into the air. The new system is a sealed system capturing and processing hydrocarbons, this system is more complicated and adds more parts (which, of course, adds more points of failure).
2010 and Earlier Vented Fuel System
2011 and Later Diurnal Fuel System
Slow fueling, splash-back and air sucking into the tank when the cap is opened to fill problems can often come from a venting issue – common with with the inlet control valve – P-trap or fill (see diagram above). Also, you cannot fill these tanks completely as they have an air gap purposely designed in them to allow for expansion. Sometimes the Carbon Canisters can also get clogged, but that is usually with older boats
Here's a link to a pretty good video on the subject from Perko: https://www.perko.com/sstv_video/sstv_fuelsystems/
Now comes the update, the diurnal system has been modified on the 2020 model year boats to a less complicated design (welcome to the slow motion of government change). Maybe the newer design will eliminate the problems of its predecessor:
Thanks,
Dean