tripped breaker

when i go fast across the lake it will trip my breaker and I have to reset it.When i come to a stop my stero will play.When i turn the key to ass the stero won't play i have to reset the breaker.

little bit of help

Provide a little more information.

Like:

What type of boat? Which engine?
Is the alternator stock, or did you upgrade?
Did you change any of the wiring with respect to the alternator/battery?
Do you have big ass amps on the stereo?

When you say the breaker trips when you go fast, how fast?

Is it a function of speed, time, or hitting wakes hard?

Here is something to try that would help identify the problem: Put the boat in neutral, but rev it up to the same RPM that you would be going when the breaker trips. Let it run there for as long as it would take to trip the breaker if you were speeding across the lake.

Did the breaker trip?

If yes, then somehow the high engine RPMs is causing excessive current to flow throught the breaker. One way this could happen is if the alternator output was connected on the "load" side of the breaker instead of the "battery" side. I have never seen a boat wired this way from the factory but I have seen a lot of people make this mistake when they upgrade their alternator.

Another "pot shot" at fixing the problem would be to simply replace the breaker. They do go bad occasionally, and a typical failure is for them to get weak and start tripping at too low a current. High heat will increase the tendency for the breaker to trip, as will vibration.

If your breaker is mounted on the engine (a typical spot) then perhaps the high speed run is causing a lot of heat from the engine, along with a higher frequency vibration to make a weak breaker trip. Just replacing the breaker with a new one might solve the problem.

What confuses me though is the statement: "When i come to a stop my stero will play.When i turn the key to ass the stero won't play"

By "come to a stop" do you mean you are at idle, but with the engine still running, or can you actually shut the engine off and still play the stereo?

If you mean you are at idle but the engine is still running then it supports the theroy that the alternator is wired to the load side of the breaker instead of the battery side. Once the breaker trips, the battery is disconnected from the circuit but the alternator is still providing the necessary power. As soon as you shut the engine off, however, there is no longer a source of power until you reset the breaker.

If this is the case, then you really want to rewire the alternator so that it connects to the battery side of the breaker. The normal wiring of the alternator has a fairly good size wire that connects down to the starter relay or the starter itself.

When the alternator is wired to the load side of the breaker you are forcing all the charging current to pass through the breaker on its way to the battery. The alternator provides its maximum output at high RPMs so the high speed runs is when the alternator might be cranking its full rated load.

If the breaker is rated at 30 amps, and the alternator is pumping 50 amps into the battery, the breaker is going to trip.

Rod

The boat is an 89 MC Tristar with a 351 motor 260 hp,alternator is stock.Tied in two other batteries positive to negative and so on have switch to charge all 3 or just 1 that starts my boat and runs everything else.The 1 is the original battery or just the stock 1.Did not touch anything on alternator or other wiring
just ran all new battery cable.I do have amps 2 kicker 800.2 all the cables are 0 gauge on pos plus neg.If I am just cruising it doesn't happen only after pretty much full throttle to were ever I am going.When I come to an idle the stero will play.When I turn the boat off and go to ass the stero,blower,lights nothing will work until I flip the breaker or push the reset.Sorry about the incomplete post and thank you Rod for your time.Don't have access to computer at home and leaving now from work will check first thing in the morning again thank you.

did you say "Tied in two other batteries positive to negative ", thats your problem. Dont even start the boat till it is fixed to positive to positive and negative to negative. You are feeding 24 volts somewhere or loading down your alt trying to charge a 24 volt bank?

He did go pos to pos and neg to neg.Idon't know to much about that stuff that's why he did it.Just hearing what he says and put it in my post.

Robert:

It sure sounds like the alternator is wired to the load side of the circuit breaker, which is very, very wrong!

As I mentioned above, it may NOT be the cause of the breaker tripping, but it is still bad to have it wired that way.

How long have you owned the boat? If you bought it used then perhaps a previous owner rewired the alternator.

I would start by having the alternator rewired properly. If the breaker still trips then I would change the breaker.

Rod

Robert,
After reading your post, I first guessed you had a MC...I was right.

I have had the same problem all summer. I did the following and it cleared up the problem:
Remove all batteries, chekc them on a home charger or at your local service station. If bad, replace (3-4 years is reasonable life-time for any battery)
Clean ALL cables, Grounds and connections related to the batteries. Don't forget about the connections under the dash, (Positive & Negative posts)
Clean the cables to a fro the starter.
Wiping the cables down won't help, get yourself a wire brush and really remove the old top layers to get to good metal.
REPLACE the BREAKER wiht a new one.
I even went one step further and added an Isolator to the system for seperate charging of the batteries. So far I have not had any problems, it's been about a month.
LASTLY,
Cover all connections for grounds and positive leads with "Di-Electric Grease" from the automotive store, this will keep the connections for oxidizing.

I fried 2 brandy-new Panasonic HeadUnits this summer because of this problem...glad I bought from Crutchfield!!!

KG

Breaker is a 35.Also there is a orange and purple wire coming from alt to back of breaker.I noticed that there is a jumper or loop from the red to the orange wire on back of breaker not on front is thie typical.

The current from the alternator shouldn't have to pass through the breaker to get to the battery. I suspect that some previous owner of that boat changed the wiring for some misguided reason. I highly recommend getting the alternator to attach to to the battery side of the breaker. The way yours is wired is actually dangerous.