Oil in Propane

If your rig has ever been to southern Mexico particularly near the coast and been refilled there by a mobile Propane/ Gaz truck it has been filled with a mixture of Butane and Propane!
There will be a small amount of oil present especially if the tank wasn’t used a great deal on the trip back north! This oil condenses or thickens with cold temperature!
The best cure that I have found is to wait for warmer weather or fill the Tank with fresh locally brewed Propane at home as soon as I return .
I don’t refill in Mexico on the trip home or just prior to that trip !

You should make no assumptions that “because it feels like oil and looks like it must be oil”, this is not how it works...Why??.... Because during the final stage of finishing commercial LPG treatment, the LPG undergoes a caustic treatment (sodium hydroxide) to remove ‘trace amounts’ of sulfur, then a water wash prior to commercial shipment.

The possibility of an occasional slight caustic carryover exist (due to a process upset), and any sodium hydroxide carryover looks and feels exactly like oily lubricant, thus the immediate impulse to call it oil...You might try a piece of p/h test paper to confirm.

Also, caustic is similar to acid because of it’s corrosiveness to components.

3 tons

I still have my dropper with phenylthalien. It did not blush. >6.0 ph.