fuel tank leak

[srephwed]

seems everytime i think i got it licked something else happens.filled up my mondial,parked it in the garage,now have a puddle under it.seems that the aluminium tanks were not built for the long run.i have seen many threads on leaks and their repair.is there anyone making replacement tanks of another material or are we stuck with what we got? it seems that even if you had a cheezey sheet metal tank it would be better than aluminium.even boats started using plastic.thanks to all

[tr0768]

The most common issue wioth Ferrari aluminum fuel tanks is the use of ethanol laced fuel.

There has been a lot of chatters and discussion here about the perals of ethanol in aluminum tanks. Ethanol is heavier than fuel and will settle to the bottom of your fuel tank with limited use. Ethanol is an alcohol based product and as such causes moisture draw and corrosion. My guess is that your tank is corroded and the fuel is weeping throuh the thin spots and pin holes in the tank bottom.

There is no practicle way to coat the inside of your fuel tanks due to all the baffels inside. One option is to fabricate a new bottom for your present tank and heliarc it over the exiting tank bottom. This will require scraping and cleaning your tank to very clean smooth metal, then use either dry ice or fill with water then weld the overlay. This should only be carried out by a professional welder under proper conditions.

I have heard the factory will provide a new tank at a very substantial price. I believe the 308 tanks run $2500 each. I not sure if there is anyone manufacturing fuel cells for Mondials, but you might explore that option. There is always the option of finding a used tank.

Howard Musolf
1981 308gtsi
1982 400i Cabriolet
1988 Lotus Esprit Turbo

[jonesdds]

Are you sure it's the tank itself and not one of the lines? Full vs. 1/4 full would make no difference if it were the tank. I don't see any tank leak traffic on your car here, let alone older cars....maybe I'm wrong, mines a bit newer but not much. Has yours sat a lot with fuel in the tanks.

[srephwed]

i beleive that it has been sitting a while.my gauge does not work yet so i put 3 gallons in to get to the gas station.when filled it took 4.5 gallons so i assume it sat with some fuel in it.i don't think it is the bottom because it did not start leaking till full.i have not got it back on the lift yet.

[2NA]

Could be something repairable like a broken spot weld on an internal baffle. Ernie started a thread about that happening to his 348 a while back. Corrosion, while possible is not a sure thing.

[vrsurgeon]

Sounds like a spot on the tank higher up. Perhaps a hose fitting. It would be cool if a polyethylene tank could be made in lieu of the metal. Perhaps a boat supply custom fabricator?