Need help wiring this alternator

   #1  

stuckmotor

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The Chinese alternator I bought to replace the one that came on my Polish MF 261 has a little different wiring setup. If someone could tell me which wire goes where I'd be mighty grateful. I'm beginning the thread and hope to add a link to a photo of the backs of the new and old alternators side by side soon. Adding photos to TBN is new to me so, it could take a while. I'll post a reply when I get the link to the photo in.
Thanks,
Stuck
IMG_20170430_155517_LI (2).jpg
 
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OP
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stuckmotor

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All Right! The photo of the two alternators is attached to my post. The letters at the top of the arrows indicate the letters/numbers/symbols on the back of the case. The arrow labeled BLADE points to a flat male connector from which I removed a female connector. My guess is that I need to attach the female connector to one of the lugs and the wire going to the positive battery terminal to another. I can make a pretty good guess but would like to have someone who knows for sure to tell me which wire goes where. I don't want to blow my new Chinese alternator.
Note: To the left of the uppermost lug on the new alternator is a B+. I'm on my tablet now and can't draw another arrow.
Many Thanks,
Stuck
 
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   #3  

Xfaxman

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So where there only two wires?

Any wiring diagram with the new alternator?

IMG_20170430_155517_LI (2).jpg
 
  
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stuckmotor

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Xfaxman,
Thank you for labeling the B+ lug.
I checked the box for a wiring diagram and found none, just a test report on the alternator. It passed.
There are several alternators for sale on the internet that appear to be the same as the one I have. Descriptions with some say that they are the newer internally regulated type and that some modification might be necessary when replacing the older externally regulated type. They don't describe the modification.
 
  
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stuckmotor

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I'm going to punch this question one more time in case there's an alternator expert on site on Saturday.
 
   #6  

wthompson

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"W" or "M" is connected to tach.
D+ is normally used on the dash dummy light. The D+ terminal is negative until the alternator starts to output then it switches to positive and light goes out. Dummy light has 12 volt+ on one side and the D+(actually negative) on the other, alternator outputs and D+ changes to positive. Hope this makes sense.
Do you have a schematic or know were the "30, 7 and blade" connect on tractor?

Wanted to add that you might have to add a diode inline on the D+ terminal if tractor doesn't stop.
 
  
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stuckmotor

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Wthompson,
Thank you. Your information seems to be just what I need to know! I don't have a schematic of the Chinese replacement. I think I can trace the 30 and 7 blade. Over the next few days I'll probably do some continuity testing and a great deal of thinking. I'll post again if I have more questions.
Thanks again,
Stuck
 
   #8  

snowcrash

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Sorry to bring up such an old subject, but I was wondering if you ever figured out to wire this alternator up.

I have a MF231 and the alternator is having problems so I bought one of these aftermarkets as a replacement but have no idea how to hook it up. Just wondering if you could point out where exactly each wire you have/had goes to on the new alternator and if you had to do anything special to make it work. I think my tach runs off of a cable so I don't think I would need that wire but then again I don't know.

Thanks for any help!
 
   #9  

DL Meisen

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Sorry to bring up such an old subject, but I was wondering if you ever figured out to wire this alternator up.

I have a MF231 and the alternator is having problems so I bought one of these aftermarkets as a replacement but have no idea how to hook it up. Just wondering if you could point out where exactly each wire you have/had goes to on the new alternator and if you had to do anything special to make it work. I think my tach runs off of a cable so I don't think I would need that wire but then again I don't know.

Thanks for any help!

What brand, what model alternator...

A photo of "connections" would help!

Generally D+ goes to a ALT lamp on dash board...

30 (DIN) or "B+" (SAE) are both the same electrically and go to positive side of battery... It is main output of alternator....

Dale
 
  
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stuckmotor

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I wish I could help but, I haven't installed the alternator. I jump started the tractor for a very long time then something else went wrong and I parked it. I've been borrowing my brother's tractor until I get around to fixing it.
There's some good sounding advice in this thread that I intend to go back to when I get to it.
If you figure it out before I do. I'd appreciate the same information you asked me for and should a miracle happen and I get mine done before you get yours, I'll try to put up a picture with labels.
 
 
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