Bird
Rest in Peace
Please purchase one of these and tell us how it works. I want one but am too cheap to spend twelve bucks to test it.
Self Priming 1/2" Siphon / Syphon Hose - Gas, Oil, Water, & Aquarium Siphon
You can find some cheaper such as the Triple-Seven model. In fact, if you Google "self-priming siphon" you'll find several and they all look like they're using the same brass valve. I've never owned or used one personally, but have seen my brother use one. He used to sell them when he was a Matco Tool distributor and they do work. If I were going to siphon fuel from a can into a tractor or lawnmower, I'd have one.
I see that Matco calls theirs a Magic Siphon Hose and of course, at $15.95, it's a bit more money.