Boat Runs Great... until it won't start. (fuel/voltage issue?)

[exbabylon]

Bought a new-to-me boat three weeks ago, Volvo Penta 5.0GL w/ SX outdrive (2000 Bluewater Vision 20'). test drive went great, first time out on a nearby lake it started up and ran great. We stopped for about 30 minutes swimming, fired it up, hit WOT for about 1 minute, realized we had almost missed the boat dock, backed it off really fast and BAM... it died. Would not start for the life of us, ended up getting a tow.

I read through every guide on fuel diagnostics from Don S. and the amazing other people here. Was finally able to get it to start when I got it home with the muffs by putting some gas directly into the carb (this is after replacing fuel pump relay and filter [no water in filter]). Since then it's ran great for two solid weekends until yesterday. Fired right up at the launch, ran great all day (stopped, fished, started twice), then at the last stop it fired up, ran about 1-2 minutes then the wife, who was driving, realized it was getting really shallow on her and she backed it off fast, BAM. Died and would not start again.

Still had voltmeter and other tools in the boat just in case so I ran through some quick diagnostics. Here's what I found:

Getting 10-11 volts at the fuel pump, same off the solenoid on the starter. I assumed the fuel pump had finally died, but when I put some gas directly into the carb again it fired right up. Ran all the way back to the launch (30 minutes) with no issue and at varying speeds.

Thanks all for your thoughts, suggestions and/or ideas!

 

[exbabylon]

Re: Boat Runs Great... until it won't start. (fuel/voltage issue?)

Update... I went back on the water last Sunday (a day after the original post) and had no issues start/stop/run at varying speeds all day fishing. Going back out today and will update after we get back tomorrow. Wishing someone had a thought, I'll take wild guesses at this point!

 

[vipergg]

Re: Boat Runs Great... until it won't start. (fuel/voltage issue?)

If it only happens when you back off fast sounds like maybe its ingesting some water into the engine . Maybe the flapper is missing or faulty . I had something similar happen but it just died while running and it would not even crank over after it died, just a clunk from the starter but no cranking. Took it to the dealer they initailly saw the no crank issue but on like the 4th try it turned over and ran great after that and they could not find an issue. So I'm in the same boat waiting for reoccurence. Took it out for like 2 hours the other day and it ran fine . Had filled it with non ethanol gas . I put startron in every tank so I wouldn't think it was a water issue but who knows with it just dieing out of the blue. When it died it seemed like it was hydrolocked. Dealer did not see any evidence of water on the plugs etc... My case I think I had 2 issues , maybe water where it started to die and I was cranking on the throttle where it was surging up and down before it died and maybe it ingested water and hydrolocked . The fuel filter was changed last fall with the winterization.Dealer suggested he look at the flapper setup when i bring it in for winterization which will be in about 2 weeks . Dont use it after labor day . Boats are great when they work but a pain when they dont.