Fuel tank prep. for sealing

[daithomas]

I tried this method of tank cleaning over Xmas I was quite impressed, it works.
http://www.realclassic.co.uk/techfiles/ ... moval.html
The spirits of salt was not easy to source, in the end I bought it from Amazon it took 2 days

[ColinPeck]

Spirits of salts is hydrochloric acid, commonly sold as brick cleaner from builders merchants. Probably what you'd buy from Wicks is pretty weak stuff, I ordered some min. 36% acid off eBay and have been using it for a couple of years for rust removal. A wash with washing soda afterwards will get rid of any residue acid.
It work amazingly well but take great care!! The fumes are pretty bad so use it outside, wear safety glasses and rubber gloves.



This is the after and before images of a Bantam barrel after about an hour's soak. I have a recently purchased Huntmaster head which will be receiving the same treatment in the near future. I will finish it off with my sandblaster before painting, but it's worth using the acid first as it gets in every nook and cranny much easier than blasting and saves a lot of time!
Colin

[malcolm.johnson]

I was given details of this from a pal`s "Roadholder" (Norton) magazine, because I have this job to face shortly, in order to remove an old tank lining, clean and re seal. My Square Four panel tank was restored long before my acquisition and modern petrol used since commissioning is causing the liner to deteriorate. A section on the underside was removed/refitted to allow access, presumably for dent removal prior to re-chroming and painting. I am hoping the lining was precautionary as the exterior of the tank is beautifully finished. It currently does not leak, but the thought of caustic soda seeping through somewhere, or acid finding a weak spot, does not thrill me. I am pleased you found this method good. Any additional tips would be welcome. What liner are you going to/have used? Wyldes "Tankliner"from Leeds seems to get good reports. Malcolm.

[brenton.roy]

It's worth noting that Hydrochloric does remove metal, where some other rust removal methods don't. This is not likely a problem with a solid lump, but may cause some issues where metal is thin. It is difficult to remove from cracks and seams. Where there isn't spare metal, it is worth considering another method, like electrolysis with caustic soda.

At the risk of sounding like the fun police, I want to stress the need for good safety gear and venting with Hydrochloric. The nice man who wrote the article seemed far too casual about this. 35% is around 10 molar, which is nasty stuff. It should only be used in a vented fume cupboard. It's hard to buy concentrated HCl because it is dangerous. I've seen the fumes from poorly capped bottles eat wooden and steel storage cupboards. You do NOT want to be breathing the fumes.

http://www.tmr.qld.gov.au/business-indu ... -Acid.aspx

[david.anderson]

I would not be using hydrochloric acid (muriatic acid, spirits of salts) either as it is very aggressive. Unless the acid is thoroughly removed or neutralised it will continue to eat away the metal. For rust removal try phosphoric acid. It works very well without the problems of HCl. An easy source of phosphoric acid is coca cola (none of the other brands work). Coke is very good in a fuel tank for removing rust.
David

[daithomas]

I agree that hydrochloric acid is dangerous stuff you should use it outdoors and take care, when you take the top off you will see the fumes coming from the liquid. read the article a couple of times before you start.
I used Phosphoric acid after the hydrochloric and a good wash out between. I don't like the idea of coca cola leaving sugar residues prior to sealing.(It's bad for your teeth but I don't know about your sprocket teeth)
I used SLOSH tank sealer.
After the hydrochloric wash most of the inside of the tank was down to bare metal that had the appearance of very fine bead blasting. Small areas of light rust turned to black ferric oxide after the phosphoric acid wash.
Dry the tank as quickly as possible after treatment to prevent new rust on clean bare steel.

[ian.scott]

I have always used the SLOSH sealer and my current Ariel was sealed with in the 80s and it has shown no signs of lifting.

Ian