Q: My S3 Fulvia's Coupe fuel tank is full of rust inside , so have to I change the fuel filter every 100 kilometers. This is the second tank that I change because the first one destroyed by the rust at its edges. What can I do about that? Someone told me to open the tank and to clean its inner . If I do that do you know a paint or something else to paint the inner of the tank to protect it from rust? Someone else told me to make a new tank from plastic to avoid these problems in the future but I really don't want to have plastic tank at my Fulvia.
- Tassos -, tassos@viva-lancia.com, Corfu, Greece

A: I'm sorry about the Fulvia problem. Almost certainly this was caused by poor quality petrol contaminated by water which leads to internal corrosion. Despite the in-line fuel filter you might also have some troubles inside your carbs. I agree that fitting a plastic tank is not a very desirable solution. Of course, check that the filler pipe and the pick-up pipes are not corroded and generating themselves rust.
Petrol tanks can be overhauled by specialist companies. I am afraid I cannot suggest names in Greece but a first contact could be a firm which specialises in reparing water radiators. The main hazard of repairing tanks is due to the petrol fumes: hence, tanks are first emptied and flushed with inert gasses such as nitrogen. After that they are splitted open and can be repaired (welded) like any other radiator and painted inside with a special petrol-resistant paint which again should be available through the specialists. If you are really stuck, maybe you will have to try abroad and in this case you can contact Omicron in England that should be able to suggest a professional subcontractor to you.
Finally, any repair will not overcome a problem due to bad petrol. Can't you change petrol station?
- Andrea -

Above was placed on the web somewhere in the fall of 1997. The story continues. Read the complete saga of Tassos at his personal pages.

Today, oct 7th, I received the saga of Alan Murphy (before you ask: yes, grandson of the inventor of Murphy's law) in Ireland.
- Huib -

Congratulations on a great site! I had read the saga of the rusty fuel tank several times on this site before I came to tackle the problem myself. The tank on my 1974 Series 2 car was badly rusted and perforated on both the top and bottom surfaces. I used a bolster (wide flat chisel) to separate the top from the bottom but found that it was almost impossible to do this without tearing the upper part of the tank. I opened it up anyhow to see what the interior construction was like.

There is a flat metal baffle running from front to rear (of the car) incorporating a box section (open at the top and bottom) which surrounds the fuel feed pipe that can be seen when the drain plug is removed. I think the fuel return pipe joins the fuel feed pipe somewhere in mid-air. The baffle is joined to the tank at only 4 or 6 locations by lap welds and between these joints there is up to 1 cm space around its edge which allows fuel to pass from one side to the other. I will keep the 3 aperture sections (fuel filler hole, sender unit hole and drain plug hole) and the feed, return and overflow pipe sections from this tank in case I need to fabricate on in the year 2020! I do not need to keep the shell as I have other tanks to mould from.

I was lucky to have a 1976 Series 3 car for dismantling which had been dry-stored for 10 years and had good floor and boot sections and a tank which looked excellent on the outside ...it was even half full of something which smelt like aviation fuel and burned even better! In fact the 10 year old petrol had deposited a solid crystalline substance (which looked like rust) on the lower inside half of the tank and blocking both the feed and return pipes. The top of the inside of the tank had light rust. It appeared to be of almost identical construction to the Series 2 tank, except for the routing of the feed and return pipes within the tank.

A professional radiator and fuel tank company was reluctant to open the tank or to flush it so I had to try it myself. I removed the gauze filter from the drain plug and I cleared the feed and return pipes by inserting semi-flexible wires of suitable thicknesses which remained in place for the remainder of the process. Without opening the tank, I flushed it with warm water and detergent, and then (here's the good bit) selected and counted into the tank about 50 small sharp pebbles small enough to fit through the space between the baffle and the tank! I blocked up all the holes and shook the tank around in all directions for a while (untiI I got tired!). I then replaced the pebbles with clean ones and added some de-greasant (GUNK) before sloshing and shaking for another while - I could have made up some sort of stand to do this and I could have done it a few more times, ending up with perhaps a final load of dry pebbles. Removing and counting the pebbles was a bit tedious but it worked.

All of this seemed to loosen and dissolve the deposits and the rust. I emptied the tank, rinsed it again with hot water and detergent and then steam cleaned it at a local garage by inserting the cleaning head through each aperture in turn and twisting and bending it to reach all the surfaces. By now I could see shiny and rusty metal in spots, but mostly the original white primer on the inside of the tank with a little surface rust.

I rinsed the tank with white spirits a few times (or whatever solvent is appropriate to the paint you want to use later on the inside) and allowed the tank to dry in an air-flow for a few days. Blocking up the holes again, I sloshed some thinned metal primer around the inside. I inserted more than a litre each time but most of it came out through the drain plug and I drained it back into the tin. It is important to rotate the tank every half hour or so while the paint is drying so as to avoid paint drips or runs and to keep the gaps between the baffles clear of paint. I applied two coats and left the tank to dry for a few days.

I have yet to decide whether I need to finish the inside of the tank with enamel as I suspect that the primer I have used is a lot better than what was used in 1976! I think Omicron have some sort of special slosh sealant for this purpose (and that they may disapprove of my amateurish methods!!). I should also have treated the outside of the tank (remove and replace underseal) before I began work on the inside.

I know that all this is of little use to someone with a perforated tank which is as bad as my first one but for a tank which is perforated and repairable with plastic filler or fibreglass it should keep someone going for a while! If I did not have a spare tank, I would certainly have tried to repair my perforated one before attempting to make a mould from it. I agree that welding should be avoided at all costs!

Alan