Motor shuts down first time out..please help

[wdb119]

So I bought a 2001 launch ss today with 450 hours and very clean. I take it out late this afternoon and it shuts down on me. I ran it today with the guy I bought it from for probably 15 minutes and had no problems. I trailer it back 270 miles and put it in the water 6 hours later and run it for 20 minutes at about 4700-5000 rpm's and I feel it sputter once or twice so I keep going to see if it does it again for a minute or so and stop..then it sputters some more and shuts down. It turns over hard for the next 10-15 minutes and won't turn all the way over. It finally does and runs like crap all the way back to landing. It def sounded like a fuel or air issue but I'm not the best mechanic in the world so I'm not sure. I first assume bad gas bc the guy I bought for said he filled tank up last fall and then winterized. It just seems like bad gas would've peaked its head earlier? Crappy feeling after buying and running for the first time. Would greatly appreciate thoughts and guidance.

[kvand347]

Sounds like it is fuel related to me. 270 miles might have jarred up some crud on the bottom of the gas tank and the pick up inside the tank may be clogged. Is this efi or carb motor? Fuel water separator?

If it ran like crap, it might have been in limp mode. Not sure what kind of motor is in the 2001 Launch.

[wdb119]

It is efi and has a spin on water fuel separator just beside the fuel pump. So, today I get back from out of town and check the fuel and it is clean. I then check the fuel pump and it is sucking and seems to be good. I blew through the input hose that goes from the tank to the fuel pump and it was clear. Here's what gets funny to me. I topped off my tank before I took out last week assuming there was plenty of fuel but today it seemed that my boat was just out of gas because when I took the line off of the fuel going to the fuel/water separator, no fuel came out then when I went and put fuel in (8 gallons) after that I primed it and the fuel flow to engine was great...i'm confused

[CornRickey]

I'm confused too. You went through the tank the po put in it and the one you just said you put in it in 20 minutes?

Also what do you mean by "it turns over hard"?

[wdb119]

The previous owner said he had filled the tank up last fall but before I put it in the water, I topped it off with 5 gallons. Then I ran the boat for probably 20-30 minutes before it cut out. When I was turning over, everything felt strong and firing good, it just felt like it was fuel starved. Yesterday, it really seemed like it had run out of fuel but when I went to put gas in, it only took 8 gallons. Are there separate tanks or some shut off valve?

[wotan2525]

Sounds like a fuel issue but you should also just do some regular "tune up/preventative" things. Change the oil, fuel filter, fuel/water seperator, spark plugs. Year old gas could very well be bad. I'd add a can of sea-foam or Stabil to the tank and continue to top it off with fresh gas every time you go out. It's odd that you ran for 30 minutes (should have been 3-4 gallons of gas max) before you had issues.

I'm not super knowledgeable about the EFI motors, but I know you can borrow/rent a fuel-pressure gauge at Autozone or Oreilly. This can at least tell you if you've got adequate pressure for the EFI. Also -- isn't there a dealer scan-tool available for these engines that may be able to tell you if you've got a code stored?

[wdb119]

I'm gonna take it out tomorrow and see how it runs. I put a good bit of stabil in a full tank so hopefully it will make a difference. I'm not that optimistic though. I talked to a mechanic today and he says he thinks the anti siphon valve at the tank could be sticking. I took a look at the tank today to see what I could do and the housings that attach to the tank seemed like they'd be hard to take off without screwing something up.

[CornRickey]

Fuel additive do not make bad gas good again. Dont waste your time getting fustrated again on the water. Due more problem solving. I've read before about the older boats having issues with the antisiphon also. Try setting up a temp gas tank from a outboard and rule out (or in) fuel delivery to the pump.

[Tim405]

it may not fix your problem but a swift kick to the junk of the previous owner may ease the anxiety...?

[wdb119]

I got an aux tank last night just in case it does. The previous owner swears that it wasn't doing it before. Seems like an honest guy but you never know. He hasn't run the boat at all this year bc he bought a new one. Any tips other than taking it to somebody to replace siphon valve??