Fuel tank vent help.

[iwillkechu]

I have Perko vents on my fuel tanks and they leak fuel like crazy! On the water it isn't a problem, however when I'm trailering I can actually see fuel spraying out of the vents. I mean actually spraying like a whale's blow hole! I would guess that I lose 1/2 to 1 gal of fuel per trip, depending on how far I'm driving. It leaks down the side of the boat, across the rubrail, and onto the trailer.
This is the style vent I have..


Is there a check valve behind that which may be stuck? Do I need to change out to something else? This is just crazy that it leaks so much fuel.
Please help.



Modified by iwillkechu at 11:34 PM 2/19/2012

[Sigma]

Tank is to full trailering. You fill up and then while trailering the day warms up fast, gas expands and then it sloshes out the vents.

Have you changed anything recently like different truck or hitch height?

[haveme1]

Search "fuel vent" there is a lot there.

[iwillkechu]

Haven't changed anything. This has been a chronic problem with this boat ever since I bought it. And it doesn't seem to matter if I fill up just before going to the lake or three days before. Today the tank was down to around 1/2 full and it was still spewing gas on the drive home from the lake. I'm at a loss here.

I don't mind searching for other vents, or even buying new vents. I just want to be sure it is the vent itself that is the problem and not a check valve or something else. I'd hate to buy new ones, take the time and trouble to install them and then find out that the problem is still there.

[Sigma]

If you do change it out go to the new style and no more problems vent line is in the fill tube.

No check valve that I know of

[iwillkechu]

Do you have a link for the new style?

My other question is whether or not there would be a problem just capping off the vent except for when I'm filling the tank? Would this cause a vacuum in the tank and starve my motor?

[Sigma]

Can you post a pic of the boat and vents and where they are located on the hull. They may just be to low???

The new style on the newer boats is just a regular fill tube and the vent line is connected to the neck on it

[Sigma]

Kind of like this.

Plugging will cause a vacume and motor wont run. I assume the boat is level or down slightly in front towing?

[Rollo331]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by iwillkechu &raquo;</td></tr><tr><td class="quote">Do you have a link for the new style?

My other question is whether or not there would be a problem just capping off the vent except for when I'm filling the tank? Would this cause a vacuum in the tank and starve my motor? </td></tr></table>

do not cap the vent off ! the tank will swell up like a balloon setting in your garage..depending where the tank is mounted it will push and break everything around it...i have seen tanks mounted under the floor shove the floor out of a boat...

check your vent hose and see if it has good routing and is up high goes straight to the vent.not rolled up laying lower than the tank

[m.t.hands]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by Rollo331 &raquo;</td></tr><tr><td class="quote">


check your vent hose and see if it has good routing and is up high goes straight to the vent.not rolled up laying lower than the tank</td></tr></table>

i look into this first

[marschall]

This may help,I had the same thing happen with my Cajun.What I found when looking at it,was my gas line that went to the vent,to the tank was to long,an it went down,before it went to the vent.It caused a siphon to happen.I ran it up,and tied it there.Solved my problem.