boat won't turn off

[Moneypitt]

All alternators are not the same. There are several types, some with internal regulators, some external regulators. Each "brand", be it automotive or marine, are designed to be wired a certain way. You can not "mix and match" different designs with what ever wiring happens to be in the application you are now installing a "different" design alternator into. 9 times out of 10 you will "smoke" the alternator, or the wiring, or both! The "diodes" being recomended are electrical check valves, meaning they only allow voltage to travel one way. Most alternators have a "diode trio", meaning there are a series of check valves to route the voltage. An Alternator must be "excited", which is 12 volts coming into the alternator, usually from the ignition switch, then the current produced is routed to charge the battery and power the electrical accessories, in one direction only, OUT. What you are seeing is the battery voltage is feeding in, past the "out" diode, so your ignition is being fed from the alternator, instead of the other way around. This usually results in a dead battery after sitting for a few hours, and can also prevent the engine from shutting off. You can fight this problem forever, since you have admited that this isn't an area you are real sharp in, OR, you can replace the alternator with one like you took off, or one designed for your type wiring harness, OR, you can take your boat to someone that knows how to convert the system to a "one wire", which is nothing more than a GM integral unit with the exciter side jumped in from the battery side, through a diode trio. BEWARE that enclosed engines in marine applications can and do blow up because of a spark from a non marine alternator in a bildge filled with fuel vapors. AND alternators that are not regulated correctly can destroy a new battery in a couple of hours of running. Please weigh you options carefully and I would recomend finding someone in your area that can help you get this done "by the book", it will pay off in the long run..........Ray

[Wicked Performance Boats]

All alternators are not the same. There are several types, some with internal regulators, some external regulators. Each "brand", be it automotive or marine, are designed to be wired a certain way. You can not "mix and match" different designs with what ever wiring happens to be in the application you are now installing a "different" design alternator into. 9 times out of 10 you will "smoke" the alternator, or the wiring, or both! The "diodes" being recomended are electrical check valves, meaning they only allow voltage to travel one way. Most alternators have a "diode trio", meaning there are a series of check valves to route the voltage. An Alternator must be "excited", which is 12 volts coming into the alternator, usually from the ignition switch, then the current produced is routed to charge the battery and power the electrical accessories, in one direction only, OUT. What you are seeing is the battery voltage is feeding in, past the "out" diode, so your ignition is being fed from the alternator, instead of the other way around. This usually results in a dead battery after sitting for a few hours, and can also prevent the engine from shutting off. You can fight this problem forever, since you have admited that this isn't an area you are real sharp in, OR, you can replace the alternator with one like you took off, or one designed for your type wiring harness, OR, you can take your boat to someone that knows how to convert the system to a "one wire", which is nothing more than a GM integral unit with the exciter side jumped in from the battery side, through a diode trio. BEWARE that enclosed engines in marine applications can and do blow up because of a spark from a non marine alternator in a bildge filled with fuel vapors. AND alternators that are not regulated correctly can destroy a new battery in a couple of hours of running. Please weigh you options carefully and I would recomend finding someone in your area that can help you get this done "by the book", it will pay off in the long run..........RayDamm Ray, Great job, I can't even think at 4 am. Budlight

[IMPATIENT 1]

[QUOTE=wright27] The boat starts but will not turn off
man who does header, has hotrod

[Taylorman]

Two things......... 1.. Install a diode trio in line to keep alternator from feeding voltage back into ignition................ 2.. Have alternator converted to 1 wire setup. I highly recommend the 1 wire deal.
I put diodes in my wiring when i had this problem and it did not cure the problem. I'd suggest getting a one wire alternator. I just bought one from Summit for $80.

[wright27]

All alternators are not the same. There are several types, some with internal regulators, some external regulators. Each "brand", be it automotive or marine, are designed to be wired a certain way. You can not "mix and match" different designs with what ever wiring happens to be in the application you are now installing a "different" design alternator into. 9 times out of 10 you will "smoke" the alternator, or the wiring, or both! The "diodes" being recomended are electrical check valves, meaning they only allow voltage to travel one way. Most alternators have a "diode trio", meaning there are a series of check valves to route the voltage. An Alternator must be "excited", which is 12 volts coming into the alternator, usually from the ignition switch, then the current produced is routed to charge the battery and power the electrical accessories, in one direction only, OUT. What you are seeing is the battery voltage is feeding in, past the "out" diode, so your ignition is being fed from the alternator, instead of the other way around. This usually results in a dead battery after sitting for a few hours, and can also prevent the engine from shutting off. You can fight this problem forever, since you have admited that this isn't an area you are real sharp in, OR, you can replace the alternator with one like you took off, or one designed for your type wiring harness, OR, you can take your boat to someone that knows how to convert the system to a "one wire", which is nothing more than a GM integral unit with the exciter side jumped in from the battery side, through a diode trio. BEWARE that enclosed engines in marine applications can and do blow up because of a spark from a non marine alternator in a bildge filled with fuel vapors. AND alternators that are not regulated correctly can destroy a new battery in a couple of hours of running. Please weigh you options carefully and I would recomend finding someone in your area that can help you get this done "by the book", it will pay off in the long run..........Ray
Thanks Ray. I will get a one wire. I changed a few wires and now it will shut off but the starter stays running. I am not sure if the starter is stuck in the flywheel or if it some wiring thing.

[Squirtcha?]

Is it still running?
Thanks for the laugh this morning Pat. That was friggin funny as hell.

[Big Kahunaa]

no smart ass I pulled the coil wire, but thanks for asking.
:220v:

[wright27]

:220v:
I grabed as many gasoline soaked rags as I could so I didn't get shocked.

[396_WAYS_TO_SPIT]

no smart ass I pulled the coil wire, but thanks for asking.
LMFAO you guys are silly

[sdba069]

Hey Taylorman........... The only reasons that the diodes wouldn't work would be because (1).. it was faulty or (2).. you installed them in the wrong direction. I'm assumming you installed the diode trio in the exciter wire, and not the charging lead. The GM alternators are easy to rig for one wire, but the Motorola's and Prestolite's are a little tougher. We've had to install a small resistor in the internal exciter wire to keep from backfeeding voltage to the ignition. This setup will work but will allow a very small voltage draw in the alternator. I've got 2 or 3 boats here with that setup and have not had a problem with the battery being drawn down between use.