Boat Gas Tank Venting Problems

A boat fuel tank overflow can be caused by a clog in the vent.

Boat gas tank venting problems.

Sometimes it actually shoots out in a stream though the tank is nowhere near full it would require major work to get to the tank at the point the vent tube connects. The thing is once you have a tank that s swelled up full of pressure it s a problem and creates a good chance of gas spill and leaking. Some boats will have explosion proof exhaust fans to vent the area prior to starting the engines and others will have will have proper ventilation built into the locker design. Many fuel vents have fine wire screens that keep out minute debris as well as nesting.

Boat fuel tank vent tips. Without a vent typically a small screw type fixture on the tank s cap or top a portable gas container can swell up in the hot sun forcing fuel into the outboard engine where it can spew inside. Don t trap fuel in your boat s vent line. If in doubt take the tank off the boat to open the vent and make sure that there are no fuel fumes on the boat prior to starting the motor.

When filling the tank i get an excessive amount of gas coming out of the vent on the side of the boat. Mine leaked gas around the motor hose connection down through the motor casing and on to the floor. Clean the screen on your fuel vent. Is the fuel tank vent clogged.

When installing a vent hose avoid sags aka traps anywhere in the vent line. This indicates a problem with the vent. The fuel tank vent is located on the outside of the boat normally relatively close to the fill port on the gunwale of the boat. Listen as you loosen the gas cap to check whether air rushes into the tank.

Taking a look on the outside of the hull and seeing if the vent is even there if it is corroded broken or upside down. Some outboard gas tanks have a vent that opens as pressure inside the fuel tank drops some have a simple check valve and others have a manual vent you open yourself. Captain aurora richard kittar.