New Alternator, a little confused...

sheltonchris1

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I purchased a new alternator the other day after realizing that I had put an automotive one on instead of the marine one. I was going to wire it up and realized that I wasn't sure where the wires went on this new alternator. It looks like it has some designated screw polls for different things, but I was unsure if I was doing it correctly and didn't want to cook the new alternator or battery or engine for that matter. I have the purple and red wires no problem. There are then poles labeled, L2, P, and E and I have a orange wire with a boot on it and a black wire left after hooking up the purple and red wires. It would be great if someone could give me some direction. I have already looked at the manual and can't find where it lays out exactly what goes where. I have a picture attached.
 

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Bondo

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Re: New Alternator, a little confused...

Ayuh,... What are We workin' on,..??
 

sheltonchris1

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Re: New Alternator, a little confused...

Thanks Don, I think thats all I really needed. I will give more detail if this doesn't get me where I'm going.

Thanks
 

Howard Sterndrive

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Re: New Alternator, a little confused...

an automotive alternator does not belong on a boat. A marine alternator on a gas engine needs to be spark arrested per SAE J1171.
 

Don S

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Re: New Alternator, a little confused...

You must have missed the first line of his original post Howard.

I purchased a new alternator the other day after realizing that I had put an automotive one on instead of the marine one.

He's trying to replace that Automotive with a marine. Just some confusion on how to wire the MARINE alternator.
 

sheltonchris1

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Re: New Alternator, a little confused...

Quick question addition:

I got my alternator hooked up and it doesn't seem to be maintaining the charge on the battery. As we run it, it seems that the battery is using the charge. My fuel injector is electric so it actually runs off of the battery as well as all the accessories in the boat. I hooked it up according to the manual, so I just wanted to see if anyone could pass along a little troubleshooting info.

Thanks,

Chris
 

Don S

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Re: New Alternator, a little confused...

Have the battery load tested.
 

sheltonchris1

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Re: New Alternator, a little confused...

is this something I can just carry the battery to Advanced Auto Parts and let them test it?
 

Bondo

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Re: New Alternator, a little confused...

Ayuh,... Most any Service Station should have a Battery Load Tester,..
As well as Most any place that Sells Batteries...
 

sheltonchris1

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Re: New Alternator, a little confused...

Thanks, it was actually a bad battery I found out today, so I went ahead and bought a new one. I would love it if someone would explain everything that an alternator does and what all it powers etc. Thanks
 

Don S

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Re: New Alternator, a little confused...

In a nutshell.
The battery powers all your 12V systems on the boat.
The alternators only job is to keep the battery charged.
You can not run todays engine off an alternator like you could an old automotive generator from the 50's.
 

sheltonchris1

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Re: New Alternator, a little confused...

I have heard that an alternator will not charge a battery unless it is fully charged to start with. Is this the case?
 

Don S

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Re: New Alternator, a little confused...

No.......
 

sheltonchris1

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Re: New Alternator, a little confused...

ok, i'm having an interesting problem at this point. I got a new alternator and new battery and everything is hooked up right as I checked it over. It seems that the alternator is not sending a charge to the battery because after running for a little while, if we turn off the boat there is not enough charge in the battery to crank back up. I tried running a wire directly from the alternator to the battery, but the alternator started to heat up and cause the belt to smoke so I disconnected it and gave up for the day to see if I could get some help. Any suggestions?
 

Bondo

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Re: New Alternator, a little confused...

Ayuh,... You really need a Multi-meter to see exactly what's going on....

It appears your pretty much guessing....

What are We workin' on,..??

That still seems to be an open Question as well.....
 

bigbob_FTW

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Re: New Alternator, a little confused...

take a look at the big fuse on the starter. mine went out and I had no charge.
 

sheltonchris1

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Re: New Alternator, a little confused...

When I get my multimeter, what do meter? The battery out connection on the alternator? I think I will check all the fuses as well.
 
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