Because Science is Cool

After many attempts I finally got the old fuel out of the tank, or at least the bulk of it. The final solution that seemed to work was denatured alcohol. But to be fair, I'm not sure if the success should be attributed to that particular solvent or to the duration of soak. I let it soak for 3 or 4 days which is considerably longer than I allowed any of the previous solvents to work.

Now that the sticky mess is out of the tank, I can more easily attack the rust. There are many methods I could try for this step as well (including a repeat of the dryer method I tried earlier). But the method that sounded the most interesting was the use of electrolysis. I made a couple of videos that explain the basic setup that I am using for this.

As explained in the above videos, I used a sodium carbonate and water solution as my electrolyte and a regular 12V automotive battery charger as my power source. The initial current draw upon supplying power to this setup was about 4A, though it dropped off over time (which I will mention in a subsequent post). The electrolyte began to bubble almost immediately and a brownish foam formed at the mouth of the tank. Below is picture of the anode after about 7 hours. Remember a couple of things; 1. rust from the tank is transferred to the anode, and 2. this is just the beginning, the process will probably take days.

anode before electrolysis (for comparison)

anode after about 7 hours of electrolysis