[Damon in STL]

So, I'm finally getting around to working on a project roller I purchased over three years ago. I thought the tank had been drained but I am mistaken. I removed the return line and got some drips from the hose side. I then pulled the supply side hose from the tank and got a very slow drip. I put a 5 gallon bucket under it and let it drip.....this was three days ago. I now have about 2 gallons in the bucket.

Last night I took a large zip tie and pushed it through the supply side opening of the tank and got some "squishy" resistance....but, no additional flow when I pulled it back out. Next up is to open it from the top and see what's left.

My question is what is the squishy material I felt? Gas has gone bad long ago and smells terrible! I'm wondering if this is a by product from old gas?