Hi All,
Jim king has been having problems with what has been identified as Copper
Carbonate forming on the inside of the copper fuel tanks fitted to his Stanley's.

As it breaks away from the inside of the tank it gets through the finest filters, and will gather at some point in the fuel system as if the particles are attracted to each other, slowly building a up greenish looking sludge until it blocks the fuel system at that point.

Has anyone come across this problem? Is there a substance that can be used to remove these deposits? We have tried very mild acids without success.

This has been an ongoing problem for Jim, spoiling the running of otherwise reliable cars. HELP!!

Jeff.

I passed the question on to the VSCC forum.

It was suggested that the problem comes from the additives in diesel which are known to cause the same symptoms where copper is used in the fuel system of diesel engines, so much so that copper is no longer used.

This doesn't explain why Jim has this problem when nobody else has seen it - we've all got copper pipes and air bottles if not copper tanks. The only thought I have on that is to wonder whether Jim's cars which are very original have old tanks. It is possible that recently made copper is of a much higher purity than old copper and that this might make it less susceptible to attack.

Apart from avoiding the use of diesel one answer might be to treat the tanks with "Slosh Tank" or some other product which will create a resistant lining inside the tank. This is very successful in recovering corroded steel tanks by encasing the rust and sealing pin holes.

Mike

Found this after a quick Google.

[www.catalina36.org]%

A BP document on the storage of diesel. Copper and zinc both cause accelerated ageing of diesel resulting in gummy deposits. Any water in diesel can cause growth of bacteria which form slimes which block filters - I would guess that this would be less likely in a copper tank as the copper is a strong biocide as was well known to HM navy in the days of wooden ships. Comment was also made that the slime problem is more severe in the case of biodiesels which have added ethanol which causes water to separate out and encourage the bugs.

Is there any chance that Jim is always buying from the same fuel source which may be selling diesel already contaminated with water! One suggestion as to the source of the copper carbonate is that water in the tank is absorbing carbon dioxide from the air, producing carbonic acid which reacts with the copper. Water may condense in the air space of the tank - always keep the tank well filled or drain it completely over winter storage.

Mike

A further VSCC comment is that diesel is hygroscopic and so takes up water from the air. Sodium hydroxide absorbs CO2 - could you hang a canister of this in the neck of the filler? Best method really is probably to keep the tank full to avoid condensation.

Mike

Hi Mike,

Thanks for all your suggestions, I am away at the moment, but will pass on all your comments as soon as I get home.

Regards Jeff.

On our 1916 Stanley Mt. Wagon, it had sat with a full tank of kerosene/diesel for 30 years when I purchased it. It was a tank of totally green slime. I sorted this problem out as that the fuel had a growth of bacteria. For long storage of my fuel, I now add a fuel sabilizer to prevent the bacteria growth. The additive can be purchased as most any marine fuel supplier. It seems that the fellows in the marine world have a real bad time controling this problem. The rectangular copper tanks of the Stanleys have internal ribs every 4 or 5 inches. It is impossible to completely clean out these ribs in a good tank cleaning. Even soaking the tank with carburetor cleaner didn't get rid of all of the green slime. My fuel filter gets a cleaning everytime I drive the '16. I now get a hard sand like green oxide from the tank. Maybe in about 4 more years, I will have all of the green crud out of the system. It has a 40 gallon tank. I used the 40 gallons of green slime drain from the tank for burning brush piles. It smelled terrible.