petrol tank cleaning

restoal · Post by **restoal** » Sun Mar 09, 2008 10:36 pm

what is the best stuff to use to clean out rust internally in a petrol tank.

paul knapp · Post by **paul knapp** » Mon Mar 10, 2008 2:05 am

A few ways available restoal, depending, of coarse, of how rusty the item is.
From simply placing a few handfulls of sharp stones in side with a little water or 'rust eater' solution, and giving the tank a good shake, to a little more elaborate setup as described here.
http://antique-engines.com/electrol.asp

This setup can be converted to do the inside of a tank by simply fitting the negative wire to the tank and placing the positive anode inside a piece of suitable plastic insulating (I use electrical conduit) pipe which has been drilled with a lot of holes to allow the solution to flow through. The insulated anode can be moved around inside the tank to be placed closest to the heavier? rust as required. I have used both methods with success.

Paul

GSAX1 · Post by **GSAX1** » Mon Mar 10, 2008 8:09 am

Believe it or not, black treacle (from black currant) mixed 50/50 with warm water is a potent (and cheap) rust remover. We have a type here in Norway that is used for making juice by adding water and this mixture eats rust like nothing I have ever seen. Do not drink it afterwards!!

Michael

itma · Post by **itma** » Mon Mar 10, 2008 9:06 am

The treacle trick works well, but best done in the sun so it stays warm.
Cover the tank filler as mice find it irresistable, drown in it and come out mummifiedEdited by - itma on 10 Mar 2008 09:06:54 AM

paul knapp · Post by **paul knapp** » Mon Mar 10, 2008 10:16 am

Some of the club boys here use the molasses method, but I have never tried it myself.
Just did a quick search and there are quite a few references to molasses. Here is one article.

Paul.
..........................

Everyone has heard how molasses dissolves rust, so make a trip to the local pet food and grain store and get your molasses.
The formula is two litres of molasses in 7 litres of water. Put this mixture in a plastic bucket or container and partly cover to help stop evaporation. Leave for about three weeks, down by the back fence (it pongs a bit), until it ferments. It should now have a skin on the top, which should be peeled off. Now you can immerse your rusty parts in this solution. Leave for about two weeks before removing them, by then all the rust should be dissolved (use rubber gloves, long tongs, or tie pieces of wire to the parts before you start, as this mixture contains ACETIC ACID).

After removal, wash off the brown muck straight away with a stiff brush under hot running water. As soon as the parts are dry, treat them with rust converter and paint them as soon as possible, or if not painted, wire brush and oil them. This must be done immediately because surface rust will start to form as soon as the metal is dry, because it is so clean it has no protection.

Apparently the water and molasses mixture when left exposed to air, ferments and produces, amongst other things, Acetic Acid. This reacts with the oxygen in the rust and when the iron oxide (rust) is all reduced the process stops, so the steel or iron is not affected, but the surface of the metal is now virtually in original condition and subject to immediate attack by oxygen in the air and begins to rust, so must be protected.

The benefit of using molasses is that it dissolves that rock-hard rust that even wire brushes can't touch and carborundum cloth can't reach and by using arrangements of odd-shaped containers like old concrete troughs half full of dirt and lined with heavy plastic sheet, it is possible to derust larger objects that would not stand sand blasting.

This mixture will still derust for quite some time, (six months or even more).

GSAX1 · Post by **GSAX1** » Mon Mar 10, 2008 10:36 am

Black treacle works fast, no need to leave for several weeks. After a couple hours you will notice a difference. I usually leave it overnight. Careful with paint, it will stain or dissolve.

Michael

crawsue · Post by **crawsue** » Mon Mar 10, 2008 1:55 pm

C'mon,Merlin....give us the science...I find all this stuff (like Coca Cola and pennies etc etc)fascinating.If anyone has read Alistair McLean (HMS Ullyses,etc. etc.)in one of his books (Ice Station Zebra...I think)he had to add a comment at the end regarding the removal of sugar from fuel...it was the most unusual logic..but he assured us that it would work.Read this book 4 decades ago so don't quote me!

crawsue · Post by **crawsue** » Mon Mar 10, 2008 1:56 pm

BTW where has Spriddler got to? Always enjoyed his pithy input.

Merlin · Post by **Merlin** » Mon Mar 10, 2008 3:39 pm

I have just cleaned my Greeves tank using very strong hot caustic solution followed by phosphoric acid to phosphate the surface not for the average guy.
.

restoal · Post by **restoal** » Mon Mar 10, 2008 7:04 pm

I`ll give it a go