Overhauling the rusty fuel tank

The story begins when I bought my Fulvia at the summer of 1995 . At the first time that I attempted to fill the fuel tank to the top I understood that I had a fuel leakage from the top of the fuel tank under the carpet of the boot. The result of that leakage was a black fluid that dropped from the bottom of the tank to the ground because the fuel dissolve the pitch that covers the tank to protect from rusting When I phone to the previous owner of the car he told me " Oh I forgot to tell you not to fill the tank to the top ,but this is not big problem for you ,just a few more visits to the gas station."

From all the other problems that I had with the car this was the more important because of the fire dangerous so I decided first to replace the old fuel tank with a new one , and second to find the reason of this fuel leakage to eliminate the probability of having the same problem in the future.

So I first try to find a new fuel tank. You can’t imagine how difficult was to find not new but not even second hand fuel tank for FULVIA Coupe here in GREECE . If you don’t have the possibility to find information like these I find now at the Internet , you are just like a blind man and at that time I didn’t know anything about Internet.

After many visits to stores with old spare parts in ATHENS I found a fuel tank from a S2 car that seemed to be in good condition and I bought it knowing that I had to make a little hole to the top ,to connect the pipe for the returned fuel that exists on S3 cars and does not exist to the older models. The gauge sending unit of that fuel tank was in good condition , had no rust around it so I thought that the inner of the tank had not rust too .At the same time I found in a magazine for classic cars the telephone of the Omicron Engineering in UK and I contacted them asking for a fuel tank. They answered to me that found a second hand fuel tank of a S2 car too , so as the two fuel tanks were the same type I prefer to buy the tank from Athens to avoid transport delays. That it was my big mistake because from that moment and then my adventures with the new fuel tank just begin.

I found the cause of the old tank destruction when I understand that I had an water leakage of the boot through many holes of the body .The water that throws through these holes trapped around the upper part of the fuel tank and because of the difficulty to see that water ( you have to remove the spare wheel and lift the rubber carpet ) the water stays there for a long time and destroy the upper part of the fuel tank with rust .

I put out of the car the old fuel tank and I replaced it with the new one but fortunately I didn’t throw the old one away . After exactly twenty kilometres the engine stops because of bad fuel supply .When I open the bonnet to see what is happening I show that the fuel pump couldn’t pump the fuel to the carbs because of the full of rust fuel filter. I change the filter but after fifty kilommetres I had the same problems. So I examined carefully the inner of the fuel tank with a special tool and I found that it was full of rust inside . Someone advice me to fill the tank with a special fluid that "eats" the rust so I fill it with that fluid and for many hours I shake it trying to eliminate the rust . That time I didn’t know that the inner of the tank was in very bad condition and the rust had create big holes at the metallic surface and even I put out off it too many rust, in a few weeks the rust will be created again.. That time I phoned to the man who selling me the tank from Athens to complain about it and he told me that put out that fuel from a car that was immovable for five years and put a good gauge sending unit on it because its own was destroyed by the rust .He told me that was sorry about it but it was the only one that found .

Anyway after all that elaboration of it with the antirust fluid I thought that I finished with that so I put it back to the car but now I found that the gauge sending unit was not working any more because its mechanism corrosed from the antirust fluid. I put the old gauge sending unit that was different type form the new one and for many months I change the fuel filter every two or three weeks and every two months I cleaned the carbs of the fuel rust. I lived with that problem until I decide to restore the car from the beginning .

At that time I send a question to Andrea asking from him an advice because I had the idea to change it with a plastic that someone here told me he can make with exactly the same dimensions but Andrea answered me to trying to fix the old one. After that I decide to open the rusty tank trying to examine the inner of it more carefully. Opening fuel tanks is very dangerous job by reason of the explosion probability because of the remaining petrol fumes if you trying to open that welding it so I opened it using the old fashioned way with a hammer and a cutter at the seam between the upper part of it an the rest of it. When I show the inner of it I understood that it was useless to try to restore it because it was in very bad condition by reason of rust. But the upper part of it was in good condition and I already have my old fuel tank with the destroyed upper part so I decide to create a new one with the upper part of the rusty tank and the lower part of the old tank. First of all I cleaned every metallic surface of the rust using a grinding tool and after that following the Andrea’s advice I contact with a technician of water radiators who inform me about a special petrol - resistant paint that composed of two separate fluids that have to be mixed before using it . I paint the inner of the two parts with that paint and then I was ready to weld the two parts ,but if used the usual welding tool I could destroy the paint because of the welding heat so I solder the two parts with a stuff witch used by the electrical technicians and has the advantage of melting in low temperatures. After that I cover the seam I create with polyesteric stuff to avoid little holes and I test the whole tank with pressure to be sure that there are no holes at all.. At the end I paint the outer part of the tank with black "hammered" paint and at last this was the end of my fuel tank’s adventure .Now after many kilometres I have no problem at all with that and when I look at it I feel very proud because I overhauled it with my own hands .