leaking petrol tank

I tried both Ethnolmate and Slosh in my cafe race fibreglass tank but have watched it slowly disintegrate over 6 years of use. The problems started with failing to get a decent covered of the inside of the tank. I used two lots of goo to try and achieve this. However, the roughness of the fibre matting on the inside, tended to prevent the sealant from flowing into every nook and cranny. Especially around the patrol tap mountings both of which came loose due to the Ethanol leaching down along the sides of the metal inserts. Consequently, the tank had now suffered from sagging, bubbling and even chunks falling off after just 2,500 miles of use.

Metal tanks should be easier to deal with but the choice of anti-Ethanol coating is critical in order to be 100% successful.

In my attachments look at the front end of the tank disolving and the side sagging about one inch below the Norton decal.

Fibreglass aside surely the answer is with a metal tank is to have it properly mechanically repaired by welding or otherwise rather thank mess about with sealants, otherwise it is a recurring problem..

I understand there is a chemical which will reduce the sealants to crystal in order to remove it. I'm not a chemical engineer so I can't help you with the name of it.

Yes there are Richard, there are many chemical agents and they need handling with care. Actually ethanol contaminated petrol, most petrol on sale in the UK will also do the trick. Rustbusters sell a good tank cleaner, my preferred method is a caustic bath.

I too would recommend the damage be repaired with metal but sealing thereafter is a good idea and then seeking out E0 petrol the total solution.

Is it any wonder why so many old vehicles are going up in flames!

You will be lucky to find E0 petrol at all before long.

Whatever treatment you decide to use the only way you'll get reliable results is to ensure the inside surface of the tank is thoroughly clean and not rusty. If you wish to ensure you have done your best to get to get it this way before using your coating you may wish to read my article on how to clean the inside of the tank..Perhaps it is slightly longer than needed but I had to ensure safety was uppermost in peoples mind when doing the process. I would STRONGLY recommend the product "TAPOX" it is truly excellent and totally ethanol proof. If you use this make sure you have some air blowing device like a small fan air-line or old hairdryer as the 2x part epoxy requires constant expultion of air from the inside of the tank to ensure the reaction cures. I would also recommend leaving the tank for at least a week to ensure total curing too....this is likely to be not a problem in winter? Anyway this is the article written a few years back:

http://www.realclassic.co.uk/techfiles/petrol_tank_cleaning_and_rust_removal.html

Les

Tony,

I used Caswell tank sealant on my 750 steel tank and the result was very good. I used this following a fair bit of research on various tank sealants and the overall views were that Caswell is one of the best. The URL will take you to the item I purchased. Note the advise on fibreglass tank if that is what you have .

http://www.caswelleurope.co.uk/ethanol-proof-mini-fuel-tank-sealer-kit-for-tanks-up-to-15-litres/

Prior to applying the sealant I followed the process on the website RealClassic for tank cleaning which also worked but make sure you following the process and health/safety bits. The chemicals can all be sourced from homebase for a few quid but this may not remove old sealants, only rust and the residue left by years of old petrol particulaty 4 star.

http://www.realclassic.co.uk/techfiles/petrol_tank_cleaning_and_rust_removal.html