Repairing Corroded Fuel Tank

[qystan]

I have a Bayliner Trophy powered by a 5.7 and Alpha 1 drive.<br /><br />Fuel tank started leaking! Pulled engine and cut through the engine compartment-fuel tank partition. Found the lower section about 8x8inch area of the tank that is touching the partition corroded. a few small holes are evident beneath the oxide layers.<br /><br />2 options: change the tank, but its one hell of a job to get the tank out. Its is much bigger than the space to get it out. Down side is that the replacement tank will be significantly smaller than the 90 Gal to get it in.<br /><br />Other option, cutout the bad section and glue a patch of aluminium over it. Pretty keen on this as I get to keep the capacity and the rest of the tank seems ok. What glue is good? Epoxy? Any particular type to look out for?<br /><br />What are your views? Thanks in advance.

 

[Bondo]

Re: Repairing Corroded Fuel Tank

Other option, cutout the bad section and glue a patch of aluminium over it. Pretty keen on this as I get to keep the capacity and the rest of the tank seems ok. What glue is good? Epoxy? Any particular type to look out for?<br />

I'd say this Option will lead to Early Funerals..............<br /><br />There's Only 1 Option to Fix a Leaking Aluminum Gas Tank,............<br />And,......<br />That's Replacement..............

 

[imported_Curmudgeon]

Re: Repairing Corroded Fuel Tank

Glue a patch on a fuel tank? You just included that to see if anyone would bite, right

 

[crab bait]

Re: Repairing Corroded Fuel Tank

i'm assumin' it is aluminum.. as you don't say.. <br /><br />epoxy is gas-proof.. an i would try it.. but would definately keep my eye on it..<br /><br />i'd even put a hole in a small sheet of aluminum.. patch it an see if'n it holds in a couple weeks.. an try an pry/chip/knock off the patch.. if it holds great( but still wary ) if not,,,, plan-B...<br /><br />hand sand VERY well... an many inches around.. clean well denatured alchol.. <br /><br /><br />soak a fiberglass patch in epoxy .. let set up some .. epoxy over again.. an again.. <br /><br />mite be alright.. mite not..

 

[qystan]

Re: Repairing Corroded Fuel Tank

Crab Bait<br /> Yes its aluminium.<br /><br />Bondo, Curmudgeon<br /> Ok ok, no glue! Maybe weld or rivets. <br /><br />Just got a quote for a tank to be fabricated, its both arms and legs! Installation will need a friend's arm ...any loaner out there?

 

[swimmin' for shore]

Re: Repairing Corroded Fuel Tank

Weld, or replace.<br /><br />Edit-didn't see your bottom line there...pop over to Hong Kong and barter?

 

[fishingdan]

Re: Repairing Corroded Fuel Tank

Crab....Epoxy is not gas proof. Today's gas has some alcohol in it. The small amount of alcohol is gas will eventually start to soften the epoxy. You will have epoxy in your fuel.

 

[Luna Sea]

Re: Repairing Corroded Fuel Tank

Come on, surely you can get a tank fabricated in China for I'd guess a third of what they'd go for in these here states! Learn to do the install yourself, maybe just hire a prof. glasser to hide the work. Good luck

 

[Haut Medoc]

Re: Repairing Corroded Fuel Tank

"Q", There has to be some plastic ones online, that will fit your need...They might not be an exact match, but something you can live with....I would not under any circumstances try to repair the tank.....It will always be lurking in the back of your mind, "has the patch failed"?....What fun is that?....Suck it up & replace the tank....You will have peace of mind ....JK

 

[Bondo]

Re: Repairing Corroded Fuel Tank

Originally posted by fishingdan:<br />You will have epoxy in your fuel.

No,.................<br /><br />You'll have Gas in the Bilge,..............Can you say Ka-Boom............

 

[qystan]

Re: Repairing Corroded Fuel Tank

China will be cheap, but won't be able to get it to fit under my seat for the flight back <br /><br />J.kopec<br />Tried looking for the plastic tanks. Largest is 50Gal. Have to ship them over, cost + shipping about close to fabricating.<br /><br />Thanks all for the inputs. Will change the tank.

 

[Luna Sea]

Re: Repairing Corroded Fuel Tank

Poor man's alternative is to put a couple of 30 gallon Tempo's, above deck, on either side of the cockpit. You could cover them up creatively as bench seats or whatever, until you can afford to do the job right. Don't ask how I know this one....

 

[Richard Petersen]

Re: Repairing Corroded Fuel Tank

Relace the bilge tank with the largest that fits. Then do Luna Sea job for the rest. Above deck tank is your warning reserve to get you home.

 

[qystan]

Re: Repairing Corroded Fuel Tank

Some good news, found sheetmetal shop to do it at a fraction of the boat yard. Whew! <br /><br />Now the work to cut out the old tank.

 

[qystan]

Re: Repairing Corroded Fuel Tank

Finally patched it. Used rivet-nuts for this.<br /><br />1. cutout the corroded area, no corners, everything rounded<br />2. make a frame (larger than the hole), think of it as a picture frame framing the hole<br />3. drill holes on tank to match<br />4. installed rivet nuts on the frame to provide the threaded holes<br />5. cut a cover patch the size of the frame, drill holes to match the frame<br />6. place frame on inside of the tank, patch cover on outside with gasket & sealant to seal.<br />7. bolt everything up<br /><br />You can have the frame/cover the other way round, makes no difference. Rivet-nuts are great for thin sheetmetal jobs.<br /><br />Sorry did not take pic's, should have done so.<br /><br />qystan

 

[Solittle]

Re: Repairing Corroded Fuel Tank

Qystan - My advice would be to make sure that your insurance is paid-up, stay far away from other boats and never take your family out with you.

 

[imported_bjs]

Re: Repairing Corroded Fuel Tank

theres all kinds of glue used in auto body shops it will glue your hole get a piece of whatever the tank is made of cut a square to cover the hole grind clean both pieces together you got a good fix ive done on gas tanks before works great.

 

[qystan]

Re: Repairing Corroded Fuel Tank

This is typical of repair schemes used on panels subjected to pressure loads of up to 8psi. 8psi may not sound much, but a 1 sq ft panel will take 800lbs. Derating that 10% to factor poor workmanship, it still gives a 80lb load capacity. The 11"x9" panel at 12 inches below the top is subject to less than 3lbs at full tank.<br /><br />Did not mention, but the reinforcement panels are 5052 aluminium, same as the tank material to minimise galvanic corrosion. Thickness is 2mm. The number of 4mm dia bolts holding the 11x9 inch patch is 34 at 1 inch spacing, deliberate overkill. <br /><br />Pressure tested the tank to 4psi with no leaks, tanks are factory tested at 3psi.