electronic overload

jhowell

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my wife would not allow me to buy the expensive boat I always wanted so I settled with a 19' 1981 Viking deckboat with a mercruiser 470. Which I know has multiple design issues including only a 37 amp alternator. So anyway I am looking to add a few components to my boat to bring it a little bit closer to what I want.

I have bought a stereo system that should shake the lake and plan on installing a second deep cycle battery to run just the stereo.

In the future I plan on installing a trolling motor but was told that I need to get a stronger trolling motor that runs off of 24v. This would include installing 2 more batteries.

Questions:

1. Is there a trolling motor out there that would give me enough trust that would run off a 12v battery?

2. Is there a faily cheap switch that would be able to switch between batteries?

3. Is an alternator conversion necessary to get more amps to power all this equipment?

4. What would be the best way to install all this equipment (diagram please)?
 

Don S

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Re: electronic overload

2. Attwood 4-Way Battery Selector Switch - iboats

3. Yes, and with a 470 that is the cheapest way. But it ain't cheap. Welcome to boats, they ain't cheap either.

4. Your stereo would hook to your fuse panel at the helm. Basic battery switch wiring is like the picture below. Just picture your motor in place of the outboard, and the fuse panel in the drawing is the one at the helm.


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Silvertip

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Re: electronic overload

As for trolling motors, the most thrust you will get from 12 volts is 55#. 24 volt units run up to 80# and 36 volt units up to a tick over 100#. What you intend to use the troller for will determine what you need. A 55 on that boat will be useless in any wind and will need to run somewhat above 1/2 speed on flat water. Whatever you end up with run time will depend on motor thrust and battery reserve capacity. On most boats, an electric troller should not be considered an emergency source of propulsion since the distances to be covered and speed is limited by battery capacity. You will NOT outrun a storm with an electric troller.

As for shaking the lake with your stereo system -- please don't do that. You will be a very unpopular person with others that don't share your choice of audio and especially those that own property on the lake.
 

wrench 3

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Re: electronic overload

If you are running any serious amps on that stereo you will have to run your supply back to the common at the battery switch and a ground to the battery. The boat wiring would not handle that kind of amperage.
As for the alternator it depends on the time on charge compared to the usage. I would think you will want more. I believe you have the second generation Delco alternator. If so, by changing internal components you can get it up to 68 amps.
 

Don S

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Re: electronic overload

As for the alternator it depends on the time on charge compared to the usage. I would think you will want more. I believe you have the second generation Delco alternator. If so, by changing internal components you can get it up to 68 amps.

He doesn't even have an alternator, just the rotor/stator setup like an outboard, that Merc used on the 470's
 

wrench 3

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Re: electronic overload

He doesn't even have an alternator, just the rotor/stator setup like an outboard, that Merc used on the 470's
Sorry jhowell, I was thinking of the wrong engine. I'd better do my home work better next time.
 

jhowell

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Re: electronic overload

2. Attwood 4-Way Battery Selector Switch - iboats

3. Yes, and with a 470 that is the cheapest way. But it ain't cheap. Welcome to boats, they ain't cheap either.

4. Your stereo would hook to your fuse panel at the helm. Basic battery switch wiring is like the picture below. Just picture your motor in place of the outboard, and the fuse panel in the drawing is the one at the helm.


attachment.php


SO you are suggesting having two separate circuts? one for the stereo and boat, and the other for the trolling motor?
is there a way to connect both of them.... safely please.
 

wrench 3

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Re: electronic overload

I'm not sure I understand your question properly, but If I do the answer is simple. To connect both batteries you turn the switch to the "both" position on the front view of the switch.
 

wrench 3

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Re: electronic overload

SO you are suggesting having two separate circuits? one for the stereo and boat, and the other for the trolling motor?
On reading your last post again, I believe that you don't have the correct understanding of the system. Each battery is not exclusive to any one system. All electrical loads (with the exception of something like an automatic bilge pump) are hooked up to the common on the switch and can be switched to either battery. The idea is to to run off of one battery when your not traveling and save the other to restart the main engine.
 

jhowell

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Re: electronic overload

On reading your last post again, I believe that you don't have the correct understanding of the system. Each battery is not exclusive to any one system. All electrical loads (with the exception of something like an automatic bilge pump) are hooked up to the common on the switch and can be switched to either battery. The idea is to to run off of one battery when your not traveling and save the other to restart the main engine.

my confusion comes with hooking up the batteries to the switch. I will have a 4 batteries total. 1 starting battery which is pretty straight forward on how to hook up to the switch.
Then there are the 3 deep cycle batteries, two of them will be used for the trolling motor in series = 24v and the other will be used for the sound system 12v. how do I hook up all the deep cycle batteries to the switch without blowing up the battery for the stereo, and reck the electrical system of the boat because is wasn't meant for 24v?

the only way I can see this happening is separating the electrical system of the boat and stereo which will run off of the 12v system, and the 24v trolling motor system. the 24v system will not be able to be recharged by the alternator (or whatever) and I will have to manually charge this system.

please add diagram if there is another way.
 

Don S

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Re: electronic overload

The two hooked in series for 24 V Will NOT be hooked to the battery switch. They have to be a completely different system and have their own on/off switch

Your starting battery and 1 house battery will be the only ones on the selector switch.
 

jhowell

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Re: electronic overload

The two hooked in series for 24 V Will NOT be hooked to the battery switch. They have to be a completely different system and have their own on/off switch

Your starting battery and 1 house battery will be the only ones on the selector switch.

Thank you! like I said before separate circuits.
 

Don S

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Re: electronic overload

Thank you! like I said before separate circuits.

Only separate 12 and 24 volt systems. The 12 volt system (House and starting) can be wired as in the diagram above.
 

wrench 3

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Re: electronic overload

Did my homework this time. Well actually I was was just looking up some other parts in the Sierra Marine catalog and noticed that they list a conversion kit to mount the 68 amp alternator to the 470.
 
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