Anyone know the output of the alternator purple wire?

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jhenderson
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Anyone know the output of the alternator purple wire?

My gauges stopped working, and I did what every normal person would do and rewired the ground. After all, that's the common thread, right? 

Nope. So I'm heading back up this weekend (it's 4 hours away) and I am suspecting the common purple wire from the alternator. Does anybody know what the output on that is? 

I was on the hard, so I wasn't able to run the engine long to play around, but now that it is in the water I will be playing with my multimeter. 
 

Hummina
1987 Catalina 36 MKI
#741
Bayfield, WI. Usually. 

jhenderson
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Posts: 81

Anybody? I'm four hours away from my boat, and I'm unable to find any information on it. 

Has anyone had problems with the wiring? I wired it exactly according to the schematic and the start button no longer worked. Adding a hot jump wire to the start button starts it, but I don't think that is a permanent solution. 

Hummina
1987 Catalina 36 MKI
#741
Bayfield, WI. Usually. 

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Catboat Willy
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Posts: 385

John,
What engine do you have and who made the alternator you are using ?? It is probably not the original alternator that came with your engine.  Purple is normally the engine instrument connection from the alternator.B+. Are you saying all your instruments quit working at one time, tach too ? 
Bill

Bill Dolan 1990 Catalina C-36 MKI - Hull #1041  'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte  Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'

 

jhenderson
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Posts: 81

M25XP. I'm thinking it's the original alternator. Yup, all the instruments quit, but If I jump the red wire to the lights on the gauges, th lights go on, which has me thinking the ground is fine.

--

Hummina
1987 Catalina 36 MKI
#741
Bayfield, WI. Usually. 

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Catboat Willy
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Posts: 385

John;
As yes, the purple wire. To get this done correctly, it may not be as easy as one thinks. First you need to know what alternator you have mounted on your engine. Take a look at this page (link below) and try and determine what brand alternator you have mounted on your engine. There are many different brands & types and many different wiring configurations. That will be the place to start. If you suspect that your alternator is going bad have it tested at a local shop. It might be a good idea anyway. May be that you need a replacement and the alternaltor technician will be able to guide you through the selection and correct wiring configuration for your engine. Make a note of what wire is what before removal. If you have the original Motorola alternator as supplied with some XP 25 and M-30 engines, it is no longer made but is easily replaced with newer models. It may also be possible to have your old one rebuilt. Keep us posted of your progress.....Bill
https://bpi.ebasicpower.com/charge/alternatorwiring.htm 

 

Bill Dolan 1990 Catalina C-36 MKI - Hull #1041  'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte  Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'

 

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Catboat Willy
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Posts: 385

John; Thought it might help if I posted the ABYC codes for wiring. Might help out in your finding a solution.
 Bill

Bill Dolan 1990 Catalina C-36 MKI - Hull #1041  'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte  Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'

 

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LeslieTroyer
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Posts: 533
According to the wire diagram there isn’t a purple wire on the starter. It shows a purple that it is for the glow plug relay. Looking more I found one diagram that shows a purple wire on the “k” terminal of the Mitsubishi 51A alternator. Don’t see anything for what a k terminal does. Start by seeing if you get power to the key switch, then with key on the other side of the switch ....... there is a 30A breaker in there might try and reset that.

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094
C-36 MK 1 Technical Editor. 

Commodore

 

jhenderson
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Posts: 81

Hummina
1987 Catalina 36 MKI
#741
Bayfield, WI. Usually. 

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jhenderson
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Joined: 1/9/14
Posts: 81

The purple comes from the alternator and goes to the key switch. At least that is how I've wired it. 

A Gentleman on the Diesel Boat Engine Facebook page has given me a schematic that solved his same problem. Thoughts?

Hummina
1987 Catalina 36 MKI
#741
Bayfield, WI. Usually. 

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LeslieTroyer
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Posts: 533
1) you’ve swapped the orange and yellow/red starter solenoid wires 2) made it so start works without glow plugs 3) removed Amp meter from circuit ******) you need to move the wire that was with the orange wire on the amp meter to the side with the red wire. This will put power back to you panel. All assuming the diagram represents your boat

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094
C-36 MK 1 Technical Editor. 

Commodore

 

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