Another 40A alternator alternative solution - verified after running...

OP
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Eric,

My guess is you have 28amper pan., if so others have bought part of the 40ampers wire harness to help
make the conversion:
32130-MAJ-G40 SUB-HARNESS, ALTNTR -
Heres the link I got this from:
http://koczarski.com/mmartin/ST_Maint
(follow the links for the 40a alt conversion.....), JohnO (whos posted on this thread is apparently the person to contact.)
Essentially, I think, your connecting the battery directly to the alt (via fuses) and bypassing the 28ampers external regulator/rectifier.
Like the std honda 40amper, the yam denso (which is probably a 28a) has a built in reg/rectifier.
The mechanical, and electrical changes you need to make to fit the 40amp honda denso also apply when fitting the yam denso part - so its quite a big job!

Hope this helps.

- al
 

moddy

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Greetings. I wanted to follow up with this post to find out how everything is going. I had an unusual issue with my alternator in that the 3 yellow leads a/c coming from the alternator's P3 connector don't have continuity to ground but I have continuity between two of the three leads at the P3 connector and no volts between any of the leads.
If I have continuity at any of the 3 leads to alternator is it safe to begin looking for another alternator?
Reason I ask, I performed the continuity check with the P3 connector on my own accord, it's not found in the book. The book says check continuity to ground only.
Lastly, has anyone installed this alternator in a 91-95 ST? Unless I find a 40A to upgrade with, I'm considering this as a viable option.
 
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OP
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Hi Moddy, use this

http://www.sharetheexperience.co.uk/ST1100/17 Charging System, Alternator.pdf

doc to test the alt. (if you don't have it already).
Can you expand a little on : 'If I have continuity at any of the 3 leads to alternator' - do you mean low <1 ohm resistance between pairs of yellow wires??, or yellow wire to ground?
The table and text on page 8 shows how and what to measure - including resistance between 3 ac output leads.

No one has so far used the yam alt on a 91-95 bike - at least so far on this thread.....


- al
 
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moddy

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I used the Honda Service manual and tested resistance between the ac wires, passed.
I check for ground from each of the ac wires, passed.
With no ac while the engine was running from any combination of the wires at the p3 connector (white and black wire p2 connector plugged in) I checked for continuity at the p3 connector and it chirped between two leads, but didn't get continuity with any other combination of the leads.
It's the only thing I can find wrong with it, for not getting any charge to the battery that I'm not supposed to get continuity within the stator.
 
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ST1100Y

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I checked for continuity at the p3 connector and it chirped between two leads, but didn't get continuity with any other combination of the leads. It's the only thing I can find wrong with it...
And this is the fatal issue...
Your 3-phase AC alternator lacks output on one phase, thus high current on the 12V DC side, thus risk of toasted wiring/connectors & blown VRR...
 

moddy

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Thanks for the clarification. I thought those leads were isolated otherwise, how could they have individual outputs. The hunt for another alternator begins.
 

ST1100Y

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The wiring diagram nicely shows how there 3 windings connected internally at one common point:

alternator winding_wiring.jpg
 

moddy

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Yeah, if they just rotated the image for the alternator 45? to the right it would at least resemble a flux capacitor.
 
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T
here is the rectifier I ins




this is the rectifier I installed on my o3,with a little bit of filling to make it fit in the feed through holes on the casing . It is a 40 amp rectifier and after 150 miles appears to be doing the job. That along with a new voltage reg part number was posted in previous post. Total fix was $63. Shure beats mr Honda.
 
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Ok got it I think . I used the info on here and located a part on eBay for a kabota and modified the casing to make it fit. The outside diameter was 4mm smaller so I had to file the holes that the wires go thru from the armature moving them in towards the center and checked th mouting holes for alignment. All the holes lined up and screwed back together nicely. Wish I had taken some pics of the mod. But today I got a f1 light on so now I am troubleshooting that multiple codes.
 
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