1998 Honda Shadow Aero VT 1100, I removed my gas tank from my bike frame and emptied my gas tank to clean out some rust that developed. When fuel stopped running out of my petcock on both on and reserve position. I picked up my tank and found there was still 1/2 gallon or more of fuel still in my tank. Shaking it didnĀ“t seem to do much good, and I ended up siphoned it out. After using Metal Restore, flushing the tank, once more liquid remained. Why and what is causing this, most of all how to fix it. Please help.