SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: 74 SleekCraft on August 11, 2013, 09:23:41 PM

Title: My boat turns off while running. Why?
Post by: 74 SleekCraft on August 11, 2013, 09:23:41 PM
I have a 76 miller with a ford 460. I took out this weekend and after running it for about 10 min it died while running. I tried to start it and it sounded like the battery was dead. I pulled it off the water then it started right up. Put a new battery in it put it and it ran for about 10 min then died again and sounded like the battery was dead again. I got the alternator checked its fine and battery is fine. Anyone have any ideas?
Title: Re: My boat turns off while running. Why?
Post by: GT Jets on August 11, 2013, 10:36:02 PM
I have a 76 miller with a ford 460. I took out this weekend and after running it for about 10 min it died while running. I tried to start it and it sounded like the battery was dead. I pulled it off the water then it started right up. Put a new battery in it put it and it ran for about 10 min then died again and sounded like the battery was dead again. I got the alternator checked its fine and battery is fine. Anyone have any ideas?


Not without a whole bunch more information.

Water in the oil? Fuel pressure? how old are the fuel lines? Condition of the fuel tanks? What type of fuel pump? What ignition system?


Water in any cylinder will do something similar to what you describe.

A failing ignition coil can cause it to die, but the hard crank thing is weird.

Running stupid hot will do strange things.

A  major electrical short will do what you explain...

The work is on you buddy, get some information together and we'll see if we can guess that issue...

As of right now, you could have boogers in the carburetor.  :P

GT

Title: Re: My boat turns off while running. Why?
Post by: 74 SleekCraft on August 12, 2013, 05:41:13 AM

Not without a whole bunch more information.

Water in the oil? Fuel pressure? how old are the fuel lines? Condition of the fuel tanks? What type of fuel pump? What ignition system?


Water in any cylinder will do something similar to what you describe.

A failing ignition coil can cause it to die, but the hard crank thing is weird.

Running stupid hot will do strange things.

A  major electrical short will do what you explain...

The work is on you buddy, get some information together and we'll see if we can guess that issue...

As of right now, you could have boogers in the carburetor.  :P

GT
no water in the oil. The oil pressure was at 80. The water was 100. The fuel lines look good. Has a brand new electronic fuel pump. The ignition is hei. I'm new to the boats so idk much about them yet.
Title: Re: My boat turns off while running. Why?
Post by: tunnels on August 12, 2013, 07:24:03 AM
did you check the battery cables, not just the ends butt the hole cable. Corrosion can build up in the cable itself and cause the problems you describe.
Title: Re: My boat turns off while running. Why?
Post by: TJS Nordic on August 12, 2013, 07:52:59 AM
Sounds like an ignition switch gremlin.
Title: Re: My boat turns off while running. Why?
Post by: SoCalPSD on August 12, 2013, 08:01:43 AM
Electric fuel pump? Are you running a regulator or have a gauge to know what your fuel pressure is. I hade a similar problem but only would happen when idling for long periods of time but you could be flooding the motor till it dies and the carb is still dumping fuel into after it shuts down because of the high pressure coming from the electric pump. Put to much fuel into a hot motor with a good ammount of advanced timing and now she's firing off before TDC and fighting the starter.
Title: Re: My boat turns off while running. Why?
Post by: BIG JOHNSON on August 12, 2013, 09:00:21 AM
did you check the battery cables, not just the ends butt the hole cable. Corrosion can build up in the cable itself and cause the problems you describe.
Had this problem with my work truck. If there's a section of cable that doesn't bend easily or makes crunchy crunchy when you bend it, cable is bad.
Title: Re: My boat turns off while running. Why?
Post by: h20dawg_2nv on August 13, 2013, 10:34:37 AM
Had similar issues on my suburban, turned out bad battery cables. Had the "crunch crunch" big Johnson mentioned. Replaced and issues ceased😃 hope you find it. Electrical gremlins are a serious PITA


89' Eliminator
508BBC Berkley Jet
Title: Re: My boat turns off while running. Why?
Post by: Nordic78 on August 14, 2013, 04:01:46 PM
Just a thought but I had a similar deal. If the timing is too far advanced it will run hot and die. And when it cools a bit it will crank right up. Mine was enough that it wouldn't die but if you shut it off for a few seconds it would act like the battery was low. Check the timing. Depending on the distributer the timing should be about 16 to 20 degrees BTDC. If its a point set up check the point gap. It should be about .016. If you have a dwell meter set the dwell at 30. Hope that helps.
Title: Re: My boat turns off while running. Why?
Post by: 88CARRERA on August 15, 2013, 05:04:10 AM
Bad breaker?
Title: Re: My boat turns off while running. Why?
Post by: Nordic78 on August 15, 2013, 05:53:44 AM
Well that certainly would do it.  Lol
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