Gas overflow valve/smell of gas

[MudDucker]

Glad yours was an easy fix. I've still got my floor cut open while I try to find a new tank that will fit that is not made of aluminum. Think I may be onto one finally.

[pcbayou]

Thanks, flogator, for the info on the sending unit. That's yet another thing I wouldn't have thought about on my own. As for my gas smell, replacing the vent tube may have taken care of it. So far the smell is gone. We'll see.

[pcbayou]

As for my gas smell, replacing the vent tube may have taken care of it. So far the smell is gone. We'll see.

No such luck, y'all. When I filled the tank yesterday, gas spurted from the valve as soon as I started pumping. Sure enough, the bilge again smelled strongly of gas.

I took off an inspection hatch and was able to see the top right corner of the gas tank, which appeared to be dry and had no smell. There is an electrical relay of some sort on the top, and it also appeared to be dry and intact. Could be that be the sending unit that flogator mentioned?

The next step may be to cut into the deck and look for leaks elsewhere. But it seems to me that if the tank were leaking, I would smell gas all the time. Is there something else simple that I'm overlooking?

[Steve Stinson]

You may have some sort of routing problems with your filler hose or your vent hose. I bought a brand new Sea Pro SV2100 back in 2000 that was very slow to fill at the gas pump. After several months, I began to smell gas in the bilge only after a fill-up. After trying a couple of local shops and not finding the problem I contacted Sea Pro and they sent a semi truck down to pick up my boat and take it back to their factory in either North or South Carolina.
They finally figured out that the filler hose between the cap on the gunnel and the tank was too long. It was crimped when they put the top and bottom portions of the hull together, and after rubbing on the inside of the hull for a while had worn through. So, it was only leaking when I was filling the tank. They fixed it and sent my boat back to me in short order, but it drove us all crazy for a while.

You could have a similar situation, or even a hose routing problem. If your vent hose or filler hose makes a loop or a "S" curve (like a pee trap on a sink drain), it could be holding fuel in the line until you force air to escape from the tank by filling up.

Crimped hoses, leaking hoses, and loose clamps can be a pain to find. Maybe my past experience will bring something to mind that you hadn't thought of.

- Steve Stinson

[pcbayou]

Thanks for the suggestion -- I'll add the hose routing to my list of things to look at/ask about.

[pcbayou]

Posted on this forum - problem with gas in bilge - the problem was the sending unit (top of built-in gas tank) was bad.

You could have a ... hose routing problem. If your vent hose or filler hose makes a loop or a "S" curve (like a pee trap on a sink drain), it could be holding fuel in the line until you force air to escape from the tank by filling up.

flogator and Steve Stinson nailed it. My leak also came from the sending unit, which my new favorite repair guy replaced. He also said the angle of the gas filler hose may be trapping air.

[Steve Stinson]

Glad we could help. Those issues are tough to find.