Took the boat out for the first run of the season today and it ran top notch. When leaving today from where we had been sitting for a few hours.... I got on it and it ran great and then the port motor shut down and fired right back up and ran some more. Then after running for a while both motors started shutting down. Im at a loss..... vapor lock issue was fixed last year...... New mechanical fuel pumps on the EFI 502's.
only thing I can think of is maybe trash is getting into the fuel line from the tank because when I got back home I changed the fuel/water filters and some trash came out of the filters. Any other suggestions?
Thanks

When mine did that it was an oil pressure kill switch on sender. Clean the wire or replace

Was wondering if the anti-siphon valve could cause this to happen

I had this hapen before on a boat.

Had a friends boat that had weak fuel lines from the tank to fuel pump and would suck the line shut then open back up, engines would start back up run a minute then shut down. pain to figure out. Worse part I was on Lake Erie bringing his boat back from Put in Bay because he was too hung over LOL.

Does it feel like it's starving for fuel? Generally this will lead to what I'll call a "soft" shut off where it slows down quickly, then dies. If it all of a sudden drops dead - a "hard" shut off - then I'd lean towards an electrical issue.

VST screens cold be plugged up and restricting fuel.

At what rpm is it shutting down? Hook a fuel pressure gauge to it and run it .See where the pressure goes

Thanks guys but i think i got figured out. Hey MOTOR.... put it at Aqua land yesterday and it ran great. I changed the fuel filters and found some trash in anti siphons. Forced some compressed air down the pick up rubes and it seemed to fix the problem. When your buddy restrings the boat this coming winter I'm going to need to clean the gas tank out.