Place a relieve valve in your feed line to the propane tank with a discharge back to your "dirty" drum as a safety measure. It may take a bit of plumbing to connect what you can find. And yes, the chuck key does not belong in the launcher. I saw a guy recieve a glancing strike in his shoulder from mounting a piece while talking, turning around to finish the conversation, and pushed the clutch lever. He caught Holy Hell from the guys in the shop for a week.
I did the same propane tank setup except I heat the oil before passing through the filters, not sure what gave me the idea but it seems to work really well.
save some money , get the stainless micron filter. I use a 200 , then 30 , then a 5 made out of the string.. take the stainless ones out and give them a good cleaning and toss them back in. been using them for WVO for years now. would work for WMO too.
I also wanted to say I really like the setup. You version 1 is similar to how mine is setup. I am doing it small scale for some black diesel to run in a diesel heater. I am using portable boat tanks and using shop air to push it around.
I made my own PVC housing to hold a pool filter. You can get them for like a buck at the end of the season at menards. Not sure if you have one of those lol. That is where I get them. They don't have space to take back many seasonal items so they sell them cheap! It will save that first filter a ton of abuse.
Spin on filters are a bit cheaper, Looks like you need a few wire racking to free up bench space. Good job of talking about your system. I also burn the black gold.
I made my pump from a new GM old style V8. Used epoxy on the input shaft to hold a seal around the shaft. I used a 12 volt dc motor to line drive it directly. It hooked up to the truck battery , so I could pump out of anyone's barrels.
Redneck Waste Oil Filtration. Household Water filters. Cheap shop heat