Petrol tank repair solutions?

[ArthurOntheRocks]

My 1930 AD tourer with a scuttle-mounted petrol tank is rusty, doesn't leak per se, but the rust sediment will plug up the outlet line, and starve out the carburetor. 

I've drained the tank and vacuumed it out, blast with air, and repeated that process.

I assume there are no replacement tanks, so what are my best options for repair?

I know at a restoration shop, they might cut it open, sandblast, weld up. seal and repaint... but am hoping to do a less drastic repair.

I've used a handful of "tank sealants" over the years but have never been that impressed, plus with ethanol, does anything really withstand that stuff these days?

any help or advice is appreciated. Many thanks.

[David Stepney]

I had a similar problem with my RP and eventually had to bite the bullet and have the tank cut open and professionally cleaned out. It was expensive (about £200 from memory) but was worth it. I then sealed it with Rustbuster Slosh tank sealer that is guaranteed to be ethanol proof. (about £28 for a tin). The work was carried out in January 2019. I also subsequently replaced the fuel line from front to back. I have not had any fuel supply issues since.

[Dave Mann]

            My technique is to fill the tank with Bilt Hamber's Deox C to clean all the rust out of fuel tanks, decanting it out into a container frequently to check progress and remove all the loose stuff. I've just done an RP tank for a friend and it even cleaned the gauze round the outlet. If it does reveal a hole it can be easily soldered up.

[John Mason]

One way to clear out the rust is to remove it from the car and put some sharpe stone chips inside. Shake the tank well or. Better still if possible strap it to a large wheel and have the wheel rotate for about an hour. Then empty and flush out well. Do the flushing several times until all the crud has washed out. Then seal will a sealant such as David suggests.

John Mason

[Dennis Nicholas]

Deox C, as above would be my favourite and copper patch soldered over any holes. Done the copper patch on my Nippy tank many years ago.......good big irons kept hot.

Or get a nice new stainless one made.

Dennis

[andrew34ruby]

Large sharp stones and a shovel full of large gravel is useful. Strap the tank to a cement mixer and run it for an hour. Reposition the tank and repeat. I've never tried any slosh sealant.

Have also welded plenty of tanks, MIG and oxy-acetylene. Fill the tank nine tenths full of water and weld at the top.

[Renaud]

Hi Arthur,

Here we have a well known established chemical company specialized in old vehicles.

Here's their product and a little video about tank sealing. I used it with success, no worry about ethanol content.
Restom

[Duncan Grimmond]

I soldered up a leaky seam in a Land Rover petrol tank today, exhaust running into the filler neck. On testing with some petrol and the air line blowing in there was a tiny weep so it had to be re-done, again with the exhaust running in.
However good the reputation of sealing products I seem to have a deep-seated prejudice against them and prefer a mechanical fix, probably from years of riding a Norton Dommie with a leaky tank in my youth. No amount of gubbins from all sorts of promised "Wunder-Sele" worked... mind you things have progressed in the world of plastics since 1969!

[Renaud]

They did too indeed Duncan. That said this is quite simply I believe some epoxy which is both really adhesive to metals, (not stainless steel though) and even better if rotted, and does well too with ethanol. ULM's tanks are made of epoxy and I suppose those guys don't want to fall?
So what?

[Hedd_Jones]

I had forgotten how good 'Bakers' flux was. I've just soldered up a pit hole in the sump of the Gordon England. It was pretty manky. Quickly cleaned with the die grinder, a gob of flux, some heat amd a prod of solder and it was done.

I was sure there was oil in it, and the guts were oily, but there was nearly no oil in it when I drained it to take the sump off. 

I assume its all on the roof of my traction engine!

---

P. S

I only had a rusty and holed tank for my RL saloon when I restored it. Difficult things to find. The holes were in deep pits on the bit that say against the bulkhead. After a wirebrush, a rattle around with some stones, and some jenolite, I plastered some Plastic Padding 'Poxy' metal into the pits, sanded until smooth, and used some 'Bill Hirch' slosh sealant from the Complete Automobilist. That was 21 years ago. No problems since. I did the same to the Microplas bodied special I had, which had a big 7 tank in it. I used Oxalic Acid in that tank to clean it inside. The outside had at some point been repaired with fibreglass. I didnt keep that long enough to fi d out if it was still good stuff. 

You can buy it on ebay. Search 'Gas Tank Sealer' (Its an American Product)