Gas tank repair

[Fishtails]

Hey guys, now that I've called it a wrap on the 09 trolling sesason , I'm starting to work on the boat for next year. After a 300+ hour season, we got a few things that need fixing before I can even start to think about upgrades.

First task...a gas smell in the front of the boat that developed a couple trips ago. There has been no gas (or gas smell) in the bilge, rather it's towards the front of the tank. This past trip it got worse, and we actually got a small amount of standing gasoline on the floor where it steps down in the cuddy.

We figured it was the fill or vent tube....not sure yet? The tank has foam packed around it, and the foam towards the front of the tank is gas logged. Do aluminium tanks ever develop pin holes? I guess I need to pull the tank to get all the foam out and clean under the tank. Then I need to find the source. Any suggestions on how to pressure test the tank? I've never done this before.

Thanks!!

[L&M]

Not a good thing Rod. And yes aluminum tanks will oxidize over time due to moister & or chemical in balances. Once you get it out & cleaned off some unless the leak is evident. Have a radiator or tank shop pressure it for you. As you said check the vent & fill hoses close for any dry rot as well & replace em.

[Fishtails]

Thanks Hank....I'll do that. I think it's going to take some major effort to get the tank out. I'm sure glad this popped up at the end of the season! If it's the tank, are there any good sources for new gas tanks?

[L&M]

If it;s a small pin hole or area to repair & the basic tank is sound it can be welded by the right person. I have a shop up here that does a good job on them for me.

[Fishtails]

Great.....when I get the tank out and inspected I'll let you know If I need it repaired and I'll get it up to you. This is something I only want to do once....

[spoonfed-1]

Early season Rod?

If you want to get out in the bay some weekend drop me a line.

glen

[c.bonaffine]

I had A the same issue this spring. I removed the tank not A fun job. Replaced all the gas lines-fill,vent and main lines.The real problem was the gasket for the sending unit. Lots of fumes and an actual leak when the gas tank was full. The gasket for the sending unit is A standard size if it is A 5 hole mount. It was dry rot. Put everything back together and solved the issue. The gas lines are not cheap as they are alcohol resistant.I spent around $300.00 for all the lines. A good piece of mind though. Good luck!

[Fishtails]

Thanks for the invite....I'll be in touch Glen. I promised the wife I'd get serious about work, as we are getting into our busy season, so I brought the boat home. That don't mean I can't steal away for a day or two..... Jeff (aka Empty Hook) already got me in trouble once.

c.bonaffine, you got that right about it not being a fun job!! In fact, it sux! I'd be very tempted to pressure test it in the boat, but if I don't pull the tank and get all that foam out the smell and hazard will remain, at least to some degree. SO....I forge on but I don't see me getting it out for several days. It's a slow process and I can't stand it for more than an hour at a time. Thanks for the tip....I'm replacing it all, so I'll replace that too!!

[big easy]

Don't foam it back in,when you replace it.The very reason most aluminum tanks fail,is because of the foam.all foam eventually absorbs water,even though it's closed cell.

When any water,and especially saltwater,remains in contact with the aluminum tank,it starts the corrosion,and eventually pinhole leaks.

When you replace it,mount it,so that it is a bit off the bottom,and sides,so that water isn't permanently in contact with it.This is a huge issue with saltwater boats,that have foamed in tanks.

Most high end boat builders have stopped foaming in their tanks,because of this,and have switched to mechanical fastening methods.

Here's a good article,on tank installation

http://marinesurvey.com/yacht/fueltank.htm

[Splitshot115]

Correct me if I'm wrong, the fuel hoses have to be Coast Guard approved when replaced.

[ray koziatek]

yes definatly ,the coast guard wont come to inspect its just stamped (labeled)on the hose,much like ,flares,pfds,and such

[Fishtails]

Just found the problem....it's not the tank. The fill hose has a decent size hole at the bend. It was not noticable until I removed it.

[dieselhp]

Sounds like a easy fix!