Do you have something to provide a level measurement on the tank up high?
Unfortunately, the fill level is determined by the good old Mark I eyeball. I've thought about tapping into the outlet & running a clear tube up the front of the tank with a floating ball as a gauge. I did that once before on a water drum used for watering - the clear tubing didn't last long, the sun caused it to become opaque. A glass tube wouldn't have that problem, but would introduce other problems.
I've been considering using two of the HEP-02A pumps in parallel (giving ~60gph flow), but that is looking like more of a project than it's worth. What with buying the pumps, fuel line, fuse blocks, terminal blocks, etc., then actually building a one-use device, it's time to consider something a bit simpler. I'd mentioned earlier that rebuilding/modifying the platform to enable lowering the tank to the ground is an option, it's starting to look like the better option.
I hadn't thought of using a trolley system, I was thinking of a ramp (the tank has wheels) with a hand winch. A trolley would have a smaller footprint, and, if designed right, would allow it to be used for raising/lowering other heavier objects. A chain hoist might come in handy for a couple other projects too. Lowering to the ground to fill would also make judging the fill level easier.
I'd considered the high pressure/high volume, drop it in the tank pumps. The high pressure was a concern, even 75psi could cause a lot of splashing. And if the outlet got loose, there would be a lot of gas coming out of a hose whipping about like an injured snake.
Once upon a time, many years ago, a cousin was using gasoline as parts cleaner. He'd been working with the gas in an oil drain pan at the front of his 2 car garage, with the door open, for an hour or so. Thinking it was time for a cigarette, he lit his lighter. Fortunately, he only lost his eyebrows & the hair at the front of his head.
I haven't forgotten that day.
