Fuel tank: replace or repair?

[Lseven]

I remember ages ago watching an old Chinese guy fixing a tank, that he simply cleaned up and used a roofers soldering iron on. There was no drama, and he just reheated it away from the tank as needed. Barry

[cal44]

If you must repair it, have it boiled out. Then all fuels are gone, meaning no fumes. Remember fumes ignite, not the gasoline. Yes, it can be welded/brazed. There are guys that do these things all the time. I see brazing on a small patch as a solution. Welding (mild steel) such thin wall is tricky so brazing might be your answer.

[Europatc]

Alan I have seen a fuel tank steam cleaned for hours. The welder then set about adding a new fitting to the tank. next thing one almighty bang, he was thrown to the other side of the workshop. He was in hospital for a long time. Never ever take chances when there is no need
happy motoring
Stuart

[robertverhey]

I'd be pretty nervous about putting flame anywhere near an empty old tank.....can the filler spout be sealed, tank inverted and then and tank filled almost to the "top" with water? Would welding/brazing be safe then?

Alternatively is it possible to affix a suitably sealed and gasketed metal patch using blind rivets? You are fortunate that the hole is on a flat section.....and if it does weep after that, one of those proprietary tank sealing kits should complete the bodge I mean job.

Just some other ideas......shoot 'em down if you like!

[Berw]

Woo you can buy tanks!! I had a sprint in the 70's the tank lasted about 2 years. they sit in the bottom of the boot on the 'baby' and of course the boots leaks, and I remember mine was petro patch al over when I sold the car, One of the things I liked about the +2 when I stripped mine the other week was the tank sitting up on the top of the diff so It didn't sit in water. But its intersting you can buy things 40 years latter that were not available when the car was current.

[Sea Ranch]

Yeah, great point. With some old things, after a certain point, the support starts to increase.

Very true with the Elan (in large part because of this awesome forum).

[69S4]

That's probably right about the wet boot causing the fuel tank to rust. In our previous house the car had to live outside and the boot interior was wet virtually all year round. I remember drilling extra holes to let the water out.

The fuel tank started smelling soon after we moved here and had three or four pin holes in almost exactly the same place as Draenog's. I found somebody who cut the whole area out and welded in a patch about a foot wide without any problems. That lasted two years before it started smelling again and it was new tank time - a std Lotus one that, with a dry boot these days, is still rust many free years later.

[rdssdi]

Many years ago (1970's) I was at a gas station and they were attempting to repair a small leak in a Chevrolet Nomad wagon. They emptied and cleaned with soap and water. While brazing the tank fumes ignited and the tank puffed up like a huge popcorn. Needless to say the car was laid up until a replacement tank was located and purchased. At the same shop they were filling a small tubeless tire with unregulated air. The tire exploded. My ears rang for days. No one was hurt. A policeman who was across the street came to see what happened. Of course after waiting a respectable period of time.

I purchased an alloy replacement from Andy. Shipped to U.S.. Beautiful craftsmanship.

Bob

[msd1107]

I also got a Wiltshire tank. Beautiful workmanship. Adds lightness.

Also, you can have Andy put in a fuel return in case you eventually want to go fuel injection.

Cheers,

David
1968 36/7988

[cal44]

Allow me to clear up something. While using oxy/acetylene, not all gas is burned off at the flame. What some of you may have experienced is an accumulation of un-burned welding gasses in the confined space (the tank). With just the right mixture the gas will go off.

Even if a tank is fully cleared of petrol (including the fumes) it can still explode in the tank during the welding process if your torch tip is pointed in the direction of the hole.
To help prevent this, have a fresh air flow going through and out of the tank. This clears out any un-burnt fumes from the welding process. Or use wire and argon, or a larger tip and weld with side heat.

Just an opinion

[Sea Ranch]

And, Mike, I believe you have significant professional experience in this area, no?

Care to share?



Randy

[cal44]

R,
Pipeline weldor.........30+years.......give or take

[Sea Ranch]

Yup, as I thought: you're the voice of experience

So, what about this scenario: I seem to remember hearing that another approach is to almost fill the tank with water, with the repair side up. That way there is very little space inside for vapors to accumulate. Is that a viable option?