89' Mercedes Benz 300E

Update No:6

So i've pulled the tank out, we've figured that out... but how do we de-rust the inside of a fuel tank? Anyone? Take a second to think.

The answer is cheaper and easier than you might think. Electrolysis.

Mixing a tablespoon of washing soda (NOT BAKING SODA) per every gallon of water you put into the tank will make the fluid very electrolyte dense. Water on it's own isn't very conductive, contrary to what you might believe or have heard. Adding the washing soda will make it much easier for current to flow through the liquid, aiding the electrolysis process.

Here was my test piece.



The power source used here is a solid state 10A 12V charger. Digital or load sensing chargers WILL NOT work for this, as they'll think that there is a short, which there technically is, and shut off or go into protect.

You can see i have my anode (positive), an old hacksaw blade, and my cathode (negative), a piece of old plate steel. Things don't typically need to be this close for the electrolysis, but this was a test piece, and i wanted the least amount of voltage drop and the highest amount of current possible. The fluid here is 1 us gallon of water with one tablespoon of washing soda mixed in. After nearly an hour, the hacksaw blade was almost completely rusted, and the test piece was nearly clean. This is how electrolysis works.

Now, onto my anode. I pieced this together using scraps laying around in the garage. A pvc cap to align everything correctly, an old vacuum cleaner hose to act as a sort of aligning bushing, and old piece of mild steel tubing, a bit of threaded rod, a couple nuts, and a bracket made from a piece of scrap steel. You don't have to spend mucho monies to get results people.



Onto the tank. Prep is easy, i blasted what i could out with an every day garden hose and high pressure nozzle. I then used some scrap hose to plug the holes (with bolts in the end to seal), and used the old strainer and fuel hose to plug the remaining hole. The entire fuel tank is my cathode.



And here you can see the setup, well, set up.



When i said that washing soda increased the electrical potential, well, i wasn't lying. This whole setup basically turned the fuel tank into a 15 gallon battery, making a whopping 0.3V and 0.3A. Not bad for things you can steal from dad's garage and the laundry supply cupboard.

More tommorow.

Majestic as fuck.

Next step, 200hp wet nitrous shot.