Older boat alternator upgrade on the cheap

[RiversMalibu]

On 5/16/2020 at 3:35 PM, UWSkier said:

If you have a 2002 or older Indmar and are still running the original alternator, there's a cheap upgrade path if you're so inclined.  I wanted more juice because PerfectPass, a heater running on high, a circulation pump, and a blower motor running was a bit more than my old alternator was happy with to give enough extra charge to feed the battery.  So, I went with this.

https://www.dbelectrical.com/products/marine-alternator-crusader-pleasurecraft-5-0-5-7-litre.html

and one of these

https://www.ebay.com/itm/New-Alternator-Repair-Harness-fits-Delco-5SI-7SI-Marine-Alternators-19020601/273250473079?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

and got to work.  It's a pretty simple job to swap out.

First, remove old alternator.

Second, install new alternator.

Third, run an additional wire from the alternator + to the + stud on the starter, being careful to run the wire in a manner that it can't rub and ground out on the engine block over time.

Fourth, optionally run an additional wire from the alternator - to the - stud on the engine block.

Fifth, cut off the ring connector on your purple wire and solder the purple wire to BOTH LEADS from the pigtail.  Use heat shrink on all of your connections.

Result: Whereas my old alternator was only good for about 13.3-13.4v at the dash at idle with no additional load, this one gives me a nice solid 14.0v.  Before, when I'd switch everything on, my voltage would drop to a bit over 12.7.  With this one, the voltage regulator compensates for load and bumps up output to match the demand.  I can turn on every electrical accessory I've got and my voltage stays pegged at 14.0v.

Hey do you have a part number for the alternator? This link is down now 

[UWSkier]

2 hours ago, RiversMalibu said:

Hey do you have a part number for the alternator? This link is down now 

https://www.dbelectrical.com/products/new-marine-400-12298-alternator-crusader-pleasurecraft-19020608-8466-18-6288.html

[RiversMalibu]

So I have all the parts here. Like Newcomer my alt has been replaced previously with w white flat blade with 2 wires coming out of it. One was the purple excite wire. The other is a red wire that runs to a blue junction box on top of the engine. Any idea what this box is? I can’t post a picture of it. I have the 320 monsoon. 

[TheRealGman]

I have a 2001 Sunscape LSV 23. Today I changed out the old 50Amp Alternator with a new 70Amp Delco Style J&N 400-12298 with the pigtail exciter. I tied the two leads on the pigtail together, removed the ring from the PURPLE and soldered the PURPLE to both leads   Then I ran higher gauge positive (red) wire (6g), to account for the higher amp alternator, from the starter to the alternator. I did the same with the black ground wire (6g) from the Engine Block to the alternator. Just like the others, I piggybacked them most of the way with the old wire. I taped off the old Orange and Black wire at the alternator. At least in my boat, the orange wire must still be connected to the starter. 
 

Before installing the new alternator, the old bad one only gave me about 12.2 volts with the ignition key on, but not started. After install I am now getting 13.4 with the ignition key on, but not started. After starting and running at idle, I am getting 14.0 volts. After bringing the engine to 2500 rpm’s I am getting 14.4 Volts. Worked like a charm   

 

 

 

[Kjono09]

I just got this alternator and need help wiring it up. Could someone please and one post to describe we’re all four of the wires go.

1. Black ground wire to ground a nut on outside

2. Orange wire two bolt on the back side.

Where does the red and purple wire go? Where does the purple wire ago. I have the exact same old chair and don’t know where to put the last two wires

On 4/28/2021 at 4:33 PM, BlindSquirrel said:

One more question....thank you for your help on this. Did your alternator come with a grounding nut? Unless I take off the one that is already there and use it to hold the ground on. I assume this is the grounding post. 
 

 

 

[BlindSquirrel]

On 10/19/2022 at 6:13 PM, Kjono09 said:

I just got this alternator and need help wiring it up. Could someone please and one post to describe we’re all four of the wires go.

1. Black ground wire to ground a nut on outside

2. Orange wire two bolt on the back side.

Where does the red and purple wire go? Where does the purple wire ago. I have the exact same old chair and don’t know where to put the last two wires

 

Factory black ground goes to the ground on the new alternator. Also, you should run a new ground wire, from the same spot on the alternator to the main ground on the block.

The factory orange wire goes to the positive on the alternator as well as a new line that goes to the starter.

Factory Purple wire goes to the two on the new pigtail. 

Not a great pic, but not real easy to get in there.

 

Edited October 21, 2022 by BlindSquirrel

[Erico]

On 10/20/2022 at 3:59 PM, BlindSquirrel said:

Factory black ground goes to the ground on the new alternator. Also, you should run a new ground wire, from the same spot on the alternator to the main ground on the block.

The factory orange wire goes to the positive on the alternator as well as a new line that goes to the starter.

Factory Purple wire goes to the two on the new pigtail. 

Not a great pic, but not real easy to get in there.

 

Where does the little red wire go?

[BlindSquirrel]

1 hour ago, Erico said:

Where does the little red wire go?

Little red wire? I don’t think there is one. Is it in my photo?

[Erico]

Hello, my Alternator has a red with a blue strip in it.

[Erico]

7 minutes ago, BlindSquirrel said:

Little red wire? I don’t think there is one. Is it in my photo?

Hello, mine has a red with a blue strip on it. Where does this go?

[Erico]

12 minutes ago, BlindSquirrel said:

Little red wire? I don’t think there is one. Is it in my photo?

Having hard time getting photo in here.

[BlindSquirrel]

1 hour ago, Erico said:

Having hard time getting photo in here.

Become a paid member to this site, or 
Go to flickr.com and upload your photo. Then paste the url here. 

[BlindSquirrel]

1 hour ago, Erico said:

Hello, mine has a red with a blue strip on it. Where does this go?

What year boat and motor do you have?

[Erico]

3 minutes ago, BlindSquirrel said:

What year boat and motor do you have?

1985 wellscraft 248 sportsman with a 1999 5.7 GM 880 motor.

[BlindSquirrel]

1 hour ago, Erico said:

1985 wellscraft 248 sportsman with a 1999 5.7 GM 880 motor.

Well…. Maybe they used different colors for wires than Malibu did. Is that little red one in addition to the ones listed in this thread?

[Erico]

3 hours ago, BlindSquirrel said:

Well…. Maybe they used different colors for wires than Malibu did. Is that little red one in addition to the ones listed in this thread?

Its with the purple wire same connector.

[BlindSquirrel]

10 hours ago, Erico said:

Its with the purple wire same connector.

I assume it’s an excite wire and can go to the pigtail with the purple one, maybe @UWSkier knows.

[UWSkier]

No idea, sorry.

[cthuss]

I too need to replace my alternator on my 2001 Sunsetter LXi with monsoon Indmar. Any suggestions or links? Tried one of the older ones but seems to be not valid anymore. Thanks for any suggestions.

[Bozboat]

46 minutes ago, cthuss said:

I too need to replace my alternator on my 2001 Sunsetter LXi with monsoon Indmar. Any suggestions or links? Tried one of the older ones but seems to be not valid anymore. Thanks for any suggestions.

Take it to your local alternator/electric motor shop and have it rebuilt. Make certain they know it is a boat alternator, some spark shielding required for inboards