Good point about the water absorption. I don't think the tank of methanol is vented to the atmosphere. But I don't know if the tank can breathe with atmospheric pressure changes.

For that matter, I don't know how damp air is kept out of a 55 gallon drum of methanol. I guess ideally it is broken down into smaller containers all at once the first time the drum is opened.

I'm going to try a few gallons from the pump and see how it runs.