Help! : Gas Leak/1992 Classic 18'

[miolla]

Hello Fellow donzi owners:
For sometime I've been having trouble with a gas leak in my 1992' 18 classic.
Here are the symtoms:
-visible gas in the bilge area
-leaks more when full than 1/3 full
Several mechanics haved looked her over and tried different things like: Changing and sealing the sending unit. Resealing the on/off valve.
The problem: I would love to once and for all fix this tank by removing it and putting in a new one. The problem is the tank must have been put in during the building of the boat. There is no clear access to the tank to see where it is leaking. If anyone has experienced this or knows what I can do, I'd greatly appreciate it. Splitting the hull or cutting the floor out are options but I would be willing to try anything else first.

Thanks and I look forward to hearing any ideas out there.

RJ

[Forrest]

Separate the deck from the hull . . . it's the only way. Don't cut the floor.

You may have a leak along the side of the tank somewhere where salt water may have gotten trapped in the foam between the tank and the stringer or rib. Ofter times you can stick you head under the bow and see some of the tank. Look for gas soaked foam usually concentrated in one area. If it is really bad with gas fumes down there, use a fan to force in fresh air prior to getting under the bow. If you find gas soaked foam and can reach it, take a tool like a long-handle gasket scraper or a screwdriver and dig out only the gas soaked foam next to the tank, to see if you have a hole in the tank from corrosion. If you do find a hole and you can get to it, drain the tank completely, remove the fuel gauge sender unit and gas cap, and then force air in to the tank to purge out excessive fumes. A wet/dry vac with a blow port works best. After the tank is purged and while fresh air is still being blown in, use a small wire brush to remove the corrosion from the hole area. Now pack some of that Aluminum Epoxy filler that made by Evercoat that you get at West Marine into the hole with a lot of overlap. Then alow it to cure fully. Once you are satisfied with your repair job, add gas to the tank and look for leakage. Finally add back in foam. The repair should last for a number of years. If you can't fix it the leak using this method, you will need to remove the tank.

[This message has been edited by Forrest (edited 05-14-2001).]

[RickR]

Make sure your fill and vent hose are in good shape and clamped correctly.

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RICKR
mailto:riggerb@aol.comriggerb@aol.com</A>

[GeneD]

This has to be fixed right away, you don't need anyone to tell you that you are driving a highly explosive bomb there. I shudder to think what might happen.
I think Forrest gave some good advice. I find it mind boggling to consider that a 90's boat has a fuel tank problem.
As outlined above, the removal of the deck is the only way to gain total access to the tank. And since the tank is encapsulated, to prevent fuel from entering the bilge area, your hole has been leaking fuel for quite some time evidenced by your observation that it only leaks when filled to a certain point. This shows that the compartment where the fuel tank is, is full of fuel...and you need only to fill the tank a bit higher than the hole before she starts spilling over.
My thoughts are that one of the mounting tabs broke it's weld.
You GOT to remedy this right away.
We don't need any more Donzi guys in the hospital!

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GeneD
007
Melbourne, Florida

[This message has been edited by GeneD (edited 05-15-2001).]