Outboard Fuel Tank

[Mike007]

I just bought a 3 gallon Attwood fuel tank for my 6 hp outboard....been a LONG time since I have run the 6 hp motor and USED a outboard tank.,

Anyway, my issue is with this tank.....there is no vent on it to keep pressure from building....or its not working....tank keeps building up internal pressure.

Also, leaking gas around fitting on tank where hose connects.

Did I buy a defective tank, junk tank, etc.....I remember tanks years ago that never built up pressure (at least I dont recall them doing that). The leaking gas is driving me nuts.....got my garage smelling like gas bad.

Thanks!

 

[Home Cookin']

Re: Outboard Fuel Tank

Loosen the cap.

I heard recently that they stopped making vented boat cans to stop air pollution. What a crock.

The reason it's leaking at the fitting is the built-up pressure.

Also try not filling as full, and keeping it out of the sun and in relatively constant temps, if you can.

 

[UncleWillie]

Re: Outboard Fuel Tank

I recently purchased a 3 Gallon Moeller Tank. It still had the screw vent in the Cap.

The vent is there to prevent the tank from collapsing when the motor draws the fuel out.
When you are not using the tank, you actually Want the tank to pressurize! Really! It's OK!
Otherwise you are loosing fuel through evaporation.

Experiment have shown that a Vented, Full Gas Tank can loose as much as 20% per month.
Wait 6 weeks and your 3 gallon tank will only have 2 gallons in it.
Worse yet, only the lighter parts of the gasoline are evaporating. (Mostly the Butane)
After a few months your tank will contain what would appear to be a mixture of gasoline and kerosene.
This is when people will say the "Gas just went Bad!" It didn't "Just Go Bad" it evaporated!

This is what all the "CARB Compliant" issues are all about!
You can not buy a gas can today that is NOT self-sealing,
You can no longer leave the vent open. And that is not a bad thing.

 

[MH Hawker]

Re: Outboard Fuel Tank

I never close the vent screw and let the tank pressurize, but then the gas never sits more than a few days.

Now that being said, I would guess this is some sort of a new deal and how is the tank vented to the atmospherere as is required by USGA law.

 

[UncleWillie]

Re: Outboard Fuel Tank

... I would guess this is some sort of a new deal and how is the tank vented to the atmospherere as is required by USGA law.

USGA = USCG ???

On the newer boats the tank is vented similar to the way your car is vented.
It goes through a carbon Filter/Canister that absorbs the fumes.
The newest engines are now also required to have catalytic converters in the exhaust manifolds.
The New CARB (California Air Resources Board) requirements became a Federal Mandatefor all Engines Manufactured in 2010 or later.
Most manufacturers produced all the blocks they could make in 2009.
That supply is now running out.
CARB Compliance adds about $6000 to the price of a new engine. Outch!

In a couple of years you will be buying $1500 push lawn mowers with Catalytic Converters, Carbon Filters, and Fuel Injection on them!