Help - OEM Alternator Connections

[waterdog]

My new high output alternator is fried.   

I'm currently under sail between Manzanillo and Tenacatita attempting to rewire my old alternator.   Memory has failed and my pictures of the connections are on a dead computer.   So...

Does anybody know offhand what the connections are for the old motorola alternator?   

I have the positive output connected.
I have the tack wire connected.

Is there a ground wire? where does it connect?
Is there a field wire?  (a postitive connection) where does it connect? 

There seem to be a lot more terminals on the back than I thought.  I don't remember how many were connected and to what.   Thanks for any speedy answers / suggestions.

[waterdog]

Another question.  If I start my engine without making all the connections, will it fry my diodes?

Thanks!

[Rick Johnson]

Steve,

I used the diagram from Stu in the following thread when I hooked up my Balmar.  I hope it answers your question.

http://c34.org/bbs/index.php/topic,4548.0.html

Cheers,

Rick

[Stu Jackson]

Another question.  If I start my engine without making all the connections, will it fry my diodes?

Was that you who left a short message on my phone?  It cut out after about 3 words.

It shouldn't because if the AO AND the field are not connected, the field will not instruct the alternator to output.  Just to be safe, connect the AO to the house bank, the wire's there anyway.

There's no ground wire on the OEMs.

Rick's link to my sketches is the one.

[waterdog]

Thanks!   

Yes Stu that was me calling you.   I felt like I was on Millionaire doing my call a friend option and my 30 seconds ran out.

I was able to figure out from your diagram that there was no big ground wire.   So I figured if I have the output connected to the battery I wasn't going to fry.   Started the motor with no nasty popping noises or burned electrical smells. 

So I'm here in Barra de Navidad.    A little bit short of Tenacatita so no jungle tour with the corcodillos,  but then again we're tied up in one of the nicest resorts on the entire west coast of North America.   I believe it's time to go to the upper pool and work our way down the interconnecting slides through pool number two and down to the swim up bar in pool number 1.

Hopefully after a marguerita or two, I'll have this alternator thing sorted out.  It wasn't clear from the diagram what other wires I need on this thing.  There has to be a keyed hot wire to give power to regulator for the field winding right?   Where does that connect?    What are the other connections? 

Any references to purple wires or brown wires or such aren't helpful because I simple don't have those wires any more.   Descriptions of function and position are really useful.   So "run a positive wire from the key switch to the top most terminal to provide energy for the field wire" is helpful.   Something like, "the blue one goes on the right and the yellow one goes on the left" doesn't help me at all.   

[Stu Jackson]

There has to be a keyed hot wire to give power to regulator for the field winding right?   Where does that connect?    What are the other connections?

Field Wire:

I had an Auto Mac, which was wired separately to the ignition switch somehow.  I just abandoned that wire, and removed the Auto Mac, so my arrangement was different than yours.  I simply can't answer that question.

Ignition:  

Purple from old harness to ignition switch still required to "activate" alternator.

Tach:

Orange off alternator went to the brown wire in harness to the tach.

Ya already got the AO figured out!  What more can a poor "Margarita" ask for?

[waterdog]

Damn.   Two margueritas and I'm still not there.  So I need some juice for the field windings via the internal regulator.  Anybody know which terminal I would connect to?    The top one near where the alternator bolts on?   Or the other terminal lower down on the starboard side?

Please.   Please.   Don't make me drink rum to figure this out.   Last time that happened I can't really remember what happened but the security people at the Krystal Ixtapa won't let me swim in the pool any more...

[Ted Pounds]

Did you check the online manuals?  They're a little cryptic, but might be helpful to you with the alternator in front of you.  Good Luck.

[Stu Jackson]

Steve, try the wiring harness upgrade article, http://www.c34.org/wiki/index.php?title=Engine_Harness_Upgrade

The fourth diagram down has wiring showing an "excite" wire, which should be the field wire.

[waterdog]

Thanks guys.   The online manuals (I have the printed versions) don't really help.  Finding the excite wire in the harness doesn't help.   I need to know where the excite wire attaches to the alternator.   A physical diagram or description indicating which of the terminals it is on the back of the alternator (not the harness) is what I'm looking for.

[ken003]

I don't know if this will help you?  I have a 2005, probably with a different alternator?  This is the sketch I made of my original, before upgrading to a Balmar 712-80 with an MC-612.  I can tell you how these wires tie into the new setup if you need that.


Ken

[waterdog]

Wish I could draw a diagram - it's different than yours Ken.     As installed, if viewed from the back of the engine I have:

At 5 O'clock - IND LIGHT TERM (unused)
At 5:30 (immediately below IND LIGHT TERM) - AC TAP (I assume this goes to the tach)
At 7:00 - OUTPUT POS - (output to the battery bank)
At 10:00 - Mystery terminal number 1
At 2:00 - Mystery terminal number 2

I need to indentify the mystery terminals and make the appropriate connections.   

[waterdog]

I found the mystery connections here:

http://arcomarine.com/xhtml/Tech%20Marine%20Alternator%20tips.pdf

The missing terminals were BATTERY SENSE+ (10 oclock) and IGNITION+ (2 oclock)

Thanks for all your help!   It turns out that the second cup of coffee solved what neither tequila nor rum could touch.   Go figure.

[Mike and Joanne Stimmler]

I think you need to change to a different rum.