Electrical/Alternator/Breaker Issues

[mfloski]

I have recently installed and wired a three amp stereo system and a light bar. I know that my alternator is overworked right now with the load of the stereo. I am working on purchasing a new balmar alternator and regulator. The problem that I am currently experiencing is; at idle speed with boat in neutral, no problems, all systems GO. After only a minute or so of driving at any speed, I trip my 50amp breaker, stereo and other electronics cutt off for a second then come back on, boat continues to run, volt meter jumps to about 17volts. When I shut the boat off, it will not restart until I reset the breaker. Should the breaker tripping not shut off the engine? It would seem like if the amp requirements was too great my battery would start to drop in voltage, but this doesn't happen according to my volt meter on my dash. Any comments on this?

[MHayes]

RE: Electrical/Alternator/Breaker Issues

So is the 50 amp breaker only for the stereo, or is that a factory breaker for the boat's electrical system? Also, when the volt meter jumps up to 17 volts, is that right after the stereo shuts down, and then does it return to normal (i.e. 12 volts or so) after the stereo comes back on?

[mfloski]

RE: Electrical/Alternator/Breaker Issues

Yes, it is the factory breaker and yes the volt meter jumps at the same time that all electrical goes out and no it does not return to normal....just stays at about 17 volts but all systems APPEAR to run ok despite this, until I shut the boat off, then i have to reset the breaker and start all over.

[surroundsound64]

RE: Electrical/Alternator/Breaker Issues

Under no circumstance should your alternator be at 17 volts. It sounds like your voltage regulator is trying to make up for the demand the alternator cannot meet.

But when the breaker trips everything else runs normally, except all that are connected to the breaker?

Does the volt meter remain at 17 or drop to 14.6 or so after it trips?

[DavidF]

RE: Electrical/Alternator/Breaker Issues

Suspect the voltage regulator. Verify actual voltage with a multi-meter, do not trust the dash mounted gauge. By placing the meters probes on a good ground "-" and the output of the altenator "+", you should get a reading of between 13.5 and 14.7. Try with load and no load on alternator. If you are getting over 14.7, then replace the voltage regulator or the entire alternator.

[mfloski]

RE: Electrical/Alternator/Breaker Issues

With the newer alternators in our boats, you can not add an external regulator to the alternator can you?

[surroundsound64]

RE: Electrical/Alternator/Breaker Issues

I think that alternator may be externally regulated. Look on the back of your engine for a little box, it's probably black or metal (silver). It should say "neg." and "gnd." on it. If yours is externally regulated, and it is the problem, you can replace them but I don't think they are cheap.

Like David said, put a volt meter on the alternator it self and see what it's reading. First with the stereo turned off, then turn it on, or have someone else do it so you can monitor the alternator the whole time.

[DavidF]

RE: Electrical/Alternator/Breaker Issues

The newer style alternators have a built in regulator that can fail (and be replaced).

[surroundsound64]

Re: RE: Electrical/Alternator/Breaker Issues

The newer style alternators have a built in regulator that can fail (and be replaced).

Ah.

What year did that start? Do you know?

[DavidF]

RE: Re: RE: Electrical/Alternator/Breaker Issues

Not sure, probably sometime in the 80's Many people convert to new style when their remote regulator or alternator fails. Skidim sells the kit.