Gentle removal of gas tank

[amidaeus]

I posted last week about finding my under floor gas tank leaking. Well...I have decided to cut a rectangular hole in my new deck and remove the gas tank and repair/replace. My question is, could I just set the depth on my skill saw to the thickness of the deck and saw away? After the job is done can I just fill the void from the saw blade and glass over? Has any here cut a hole just big enough to remove the tank? I am trying not to damage too much of my new deck, so the least intrusive method would be great.

 

[prockvoan]

Re: Gentle removal of gas tank

Yes,you can use your saw to cut up the deck and as for as just putting the deck down and glassing it down,No!What you can do is strip out from under the deck,adding a lip all the way around the hole that you cut out,and then replace your piece of deck that you remove.Now,that is if you have the room.

 

[Indymike]

Re: Gentle removal of gas tank

Use a 45* bevel cut when you make your opening.<br />At put back time you should be able to fill the kerf from the saw with thickened epoxy to where the cut out will sit flush with the rest of the floor then glass the seam. <br /><br />Mike

 

[cajun555]

Re: Gentle removal of gas tank

Make sure theres no gas fumes to mix with the brushes on the saw, or you might have a bigger hole than you figured on. Just a thought.

 

[steve n carol]

Re: Gentle removal of gas tank

you may find that the gasoline has deteriorated the foam. My new tanks are above the floor because of this very thing. <br />Prok 'O vans, idea may be to install a removal trap door, kinda like a locker door or ski storage. good idea...sl

 

[Terry H]

Re: Gentle removal of gas tank

I like the idea of having access to the tanks and fittings.

 

[amidaeus]

Re: Gentle removal of gas tank

Thanks for the ideas, I like the hatch concept. Maybe a long stainless piano hinge on one side with a flush latch on the other!

 

[prockvoan]

Re: Gentle removal of gas tank

Thats good,now here comes the big BUT!If you leave a hatch over a gas tank,water will build up on top of the tank.Chances are down the line,water will make it in the tank,some how or another.Here we go again,USCG regs states that water will not be able to build or set on top of a gas fuel tank.Thats why most boat builders just close them in,with only acess to the vent,fill and sending unit.

 

[cc lancer]

Re: Gentle removal of gas tank

If you leave a hatch over a gas tank,water will build up on top of the tank.<br />Not necessarily, I have a 22 and a 24 both with a center mount tank with a "hatch" to them. But the floor of the boat was designed for the cover.<br />They were secured with SS crews and had some type of caulking to prevent water from entering the compartment. And the tanks are foamed in place.<br /><br /> The problem you might encounter, is getting the tank out of the hole you cut in you deck. How was the tank secured?<br />I have always disagreed with manufacturers who cover up tanks and engines, so something has to be tore up to get to the them.

 

[amidaeus]

Re: Gentle removal of gas tank

CC,<br />I am concerned with what I will have to cut out to remove the tank. If a structural piece is sawn out will I have to scab in a replacement? My tank looks to be foamed in but I only have 3 six inch holes to look through. one is at the vent and fill lines, the other is at the sending unit and lastly the fuel line to the engine. if I get it out and foam in a replacement with a hatch above it is it still up to U.S.G. code? If there is some structure holding it in, can I scab a piece in with fiberglass?

 

[Lou C]

Re: Gentle removal of gas tank

My 88 Four Winns was built with a removable hatch so you could have access to the gas tank. It is just piece of plywood covered with carpet like the rest of the floor. It is braced underneath so it does not flex when you walk on it. Since these boats usually are left with a cockpit cover on when not in use, water getting into the tank area is not ususally a problem. If I were making a hatch, I'd try to get some stainless steel and make an overhanging lip around the hatch with a rubber gasket under it. <br />The bigger issue is how to get at the tank without making sparks, even if you were to siphon all of the gas out there is still the issue of vapor. I'd consult an expert in gas tank repair before doing anything, too dangerous to take a chance.

 

[cc lancer]

Re: Gentle removal of gas tank

I am concerned with what I will have to cut out to remove the tank. If a structural piece is sawn out will I have to scab in a replacement?<br /><br />Yes<br /><br /> My tank looks to be foamed in but I only have 3 six inch holes to look through. one is at the vent and fill lines, the other is at the sending unit and lastly the fuel line to the engine.<br /><br />You said in your earlier post you pressurized the tank to get the gas out, did you check for leaks at that time? <br /><br />If I get it out and foam in a replacement with a hatch above it is it still up to U.S.G. code?<br /><br /> Yes, there are thousands of boats with a hatch to get to the gas tank.<br /><br />If there is some structure holding it in, can I scab a piece in with fiberglass?<br /><br />Yes but you are taking on a job that I would hate to have to do, I have not seen the under floor area of your boat, you may be changing the structural integrity of the boat. If there was a box built of plywood around the tank, glassed, then the tank was installed with the foam you may be able to brace off of it. But removing the old foam is a job, period.<br />Personally, I would exhaust all possibilities for a leak before I started cutting.<br />And as LouC stated, this is a dangerous job. I would try to find out where the problem is, even if I had to cut out another inspection area. Safely of course.<br />--------------------