97 150 EFI randomly shuts off

[h2oboy83]

I have a new boat with a 97 150 EFI 2 stroke. On the first outing i had some issues. It starts right up, idles fine. Quickly got onto plane and was cruising at 50 mph. When all of the sudden it shuts off. The intermintant alarm was going off which I found was the wires of the sensor were worn out. But again it would cruise for a few minutes and then shut off. So I tried to just idle it and it shut off again 2 more times. I unhooked the oil level sensor and the buzzer quit. Low speed its fine, but after about 3-5 mins on plane it will shut off. No spitting or sputtering, just like I turned the key off. And like I said, after it dies it starts right up, idles like a new motor and powers me onto plane no problem. My guess is something might be loose. I started the motor and shook alll the wiring and it wouldnt shut off. Im wondering if it might be the ignition switch wiring. It was pretty rough water that day. Any ideas?? Is this common???
Oh and all the filters were just changed and the fuel bulb just replaced.

 

[Faztbullet]

Re: 97 150 EFI randomly shuts off

When it dies can you still hear the electric fuel pump running?

 

[GlasV162]

h20boy,
I'm having similar trouble w/ my 1999 150 EFI; goes along great and then shuts down, except on mine the alarm doesn't sound. Fatzbullet, how loud is the electric fuel pump? Is it audible w/ the motor cover on?

 

[h2oboy83]

Re: 97 150 EFI randomly shuts off

I think I may have found the problem, while replacing the oil cap I found a wire from the power pack had been rubbing on the flywheel. It had worn down all the way to the copper and was grounding out on the flywheel. Hoping thats It.
GlasV, another thing I found thats odd is on the starboard side of the motor, there is a line that comes out of the engine mounted oil tank and goes to a T. One side of the T goes to the remote oil tank and the other is un-capped. It doesnt look like its leaking but I dont know if anything is suppose to be there. Is yours the same?

 

[h2oboy83]

Re: 97 150 EFI randomly shuts off

My buzzer was going off because the wires on the oil cap that make sure it has oil are were worn down and touching, making it think it was low on oil. I didnt hear the fuel pump though because it was windy and the noise of the boat moving. If the problem persists ill check that.

 

[ufm82]

Re: 97 150 EFI randomly shuts off

You can hear the pump easily if the cowl is off and the engine isn't running. Once you start the engine you probably won't be able to hear it and definitely not with the cowl on.
Having your power pack wires touch the flywheel is just like hitting the kill switch. Provided nothing else has died due to the grounding it would seem likely that you've found that issue. As for the tank lines I'd have to look at mine to check them. Not sure about that one.

 

[GlasV162]

Re: 97 150 EFI randomly shuts off

h2oboy, mine is the same on starboard side--oil line connected to a tee with one end uncapped. I just tried turning the key on mine, and I can hear the pump running. Do these pumps simply quit, or do they fail gradually by starting / stopping? With the cars I've owned that need new fuel pumps, the pump just quits and never runs again. Thanks. And h20boy, thanks for letting me jump in here; I started a thread on this a few weeks ago but no one replied. Thanks again,
John

 

[h2oboy83]

Re: 97 150 EFI randomly shuts off

Well that didn't fix it. I replaced the oil cap and still get the low oil alarm. I'm gunna look into the oil pump. I'm not sure. I'll also look into the fuel pump.

 

[h2oboy83]

Re: 97 150 EFI randomly shuts off

Just an update. Turned out to be the voltage regulator. When voltage would go above 16V it would die. Once it shut off voltage was fine and it started right up. $100 fix

 

[GlasV162]

Re: 97 150 EFI randomly shuts off

How could you tell the voltage regulator was bad? Is there a way to test it?