Solution to EPA gas tanks

[maintenanceguy]

As you probably know, the EPA changed the rules for boat gas tanks a few years ago. Just like gas cans that were changed 20+ years ago, the EPA has made manufacturers make tanks that are air tight now. If you've ever tried to fuel up your lawn mower with the newer EPA gas cans, you probably spilled a cup of gasoline on the ground because of the new EPA compliant valves in the spout. In EPA think, they prevented a tablespoon of gas from evaporating into the atmosphere by getting you to spill a cup of gasoline instead.

They applied the same forethought to boat gas tanks. Now, boat gas tanks build up pressure and swell up forcing gasoline under pressure to spill out of the outboard motor when the boat is sitting on it's trailer in your yard.

But, I have the solution, which is probably a felony that will get you a life sentence.

Drill a 3/16" hole in the top of your fuel tank close enough to the fill cap that you can reach in and touch the bottom of the hole with your finger. Install one of these vents in the hole. Then add a very thin metal washer and 10-32 nut on the underside of the vent to hold it in place. No more swollen tanks.

If you have a thicker section of plastic, I'm sure you could drill and tap the hole for a 10-32 thread and eliminate the washer.

If you store the tank sitting on it's end, make sure to choose a location that won't leak. If this vent ends up below the level of the gas, gasoline will drip from the vent.

 

[Frankenfish]

Man, you nailed it with the spilled mower gas. Really frustrating, between the EPA requirements for vapors and the whatnot else put on as flame arrestors.

Now, boat gas tanks build up pressure and swell up forcing gasoline under pressure to spill out of the outboard motor when the boat is sitting on it's trailer in your yard.

I just bought a new motor and it came with a solution for this pressure into the outboard. It has one of these between the tank and the bulb to prevent the pressure reaching the outboard. https://www.amazon.com/attwood-9300FDV7-Fuel-Demand-Valve/dp/B0053HPOBU
The tank still has to withstand the temperature and pressure fluctuations (which they say it can :---) ).

Seems to me like a band-aid for a problem that new regulations created. I haven't used my tank with it enough to have an opinion on them, but keeping the engine from flooding with gas is nice.

 

[tucker99]

Take the EPA tank cap off and remove the little rubber check valve with needle nose. Takes a second and the cap will then behave just like a regular vented cap.