Vapor Lock Again On Mothers Day Cruise

What winter summer changeover date is on the fuel pump you use? It's up to 10% that does not mean it is always 10%.

Fwiw I was having issues with mine while towing the trailer. When I shut down the fuel lines were gurgling and hot to the touch. I drained water out of the filter so I swapped out the filter, dumped in some additive, and got fresh fuel. It ran a lot better after that.

 

Try some av gas.

 

I went through a similar but more severe symptom and was pulling large amounts of air into the sediment bowl just like the video. My rubber fuel line from the tank to pump was clogged. It began sucking air slowly and then eventually the carb would draw the fuel down and it would stall. I ended up cleaning the fuel system and blowing air back through the lines. Then ran some toluene through with the fuel to help clean the varnish.
seems to be working good now. No bubbles.
After it sat a bit the fuel pump would still hold enough vacuum to fill and start normally after a while.