Alternator Charging Issues

SaltCityCafe

Been Around the Block
Ok so for starters yes I have searched and researched. I am just stumped.

I have a 71 CB750 K1
Antigravity Lithium Battery
Stock Alternator
R/R

I am getting no AC Voltage from my alternator. I have 12v going to the field coil, the stator ohms out at 0.6 on all three legs.

I start the bike and I am getting nothing off the yellow output wires from the stator.

The only thing I haven't replaced or thoroughly tested is the rotor. But the rotor doesn't have anyway to test it that I can see since its excited field and its really just a piece of cast iron spinning between the field coil and the stator.

If you can help me out with some more testing or any ideas at all I would appreciate it. I am just stumped, there is no reason why this damn thing shouldn't work.
 
If you haven't ever heard of Mike Nixon or his site www.motorcycleproject.com, you should do some reading, just make sure you don't confuse articles about DOHC and SOHCs. Unfortunately he's kinda gone commercial but you can't blame him. His info about SOHC charging is now a booklet but it's probably well worth the bucks. http://www.motorcycleproject.com/text/booknook.html#13

The other thing, if you don't get help here <no offense anyone>, check on SOHC4.net All of us are doing what we can to help people so please don't flame me. There's a lot of good guys there too. Hopefully someone will have the answer you need, and I'll be watching just in case the same problem hits one of my SOHCs.
 
Have you checked to see if there is any resistance between each of the yellow wires and ground? You should not be able to get a reading.

Also, you can test the rotor to see if it's working by hooking the white wire directly to the battery positive terminal and then seeing if a wrench sticks to it.
 
Sonreir said:
Have you checked to see if there is any resistance between each of the yellow wires and ground? You should not be able to get a reading.

Also, you can test the rotor to see if it's working by hooking the white wire directly to the battery positive terminal and then seeing if a wrench sticks to it.

Yes I have checked resistance on the yellow stator wires to ground and get no reading.

Also do you mean the white wire on the field coil to see if it becomes magnetic not the rotor? That I haven't done but I can try it.

Like I said all the individual parts seem to be working but for some reason I am just not getting any ac voltage out
 
pull the engine cover and make sure the stator wires have not unplugged them selves from the harness pigtail

and to be clear it goes from the stator housing into the engine cover and connects there IIR

here is a ebay pic if you look you will see the connectors in the harness they are under the engine cover

http://www.ebay.com/itm/69-70-Honda-CB-750-CB750-Sandcast-KO-Stator-Cover-666-/371453893481
 
SaltCityCafe said:
Also do you mean the white wire on the field coil to see if it becomes magnetic not the rotor? That I haven't done but I can try it.

The rotor is basically a big electromagnet. If you take the white wire wire coming out of the regulator and hook it up directly to the battery's positive terminal, it will activate the electromagnet. A wrench should stick to the side of your engine case.
 
Sonreir said:
The rotor is basically a big electromagnet. If you take the white wire wire coming out of the regulator and hook it up directly to the battery's positive terminal, it will activate the electromagnet. A wrench should stick to the side of your engine case.

Ah ok I get what you mean now I will give it a shot.
 
cxman said:
pull the engine cover and make sure the stator wires have not unplugged them selves from the harness pigtail

and to be clear it goes from the stator housing into the engine cover and connects there IIR

here is a ebay pic if you look you will see the connectors in the harness they are under the engine cover

http://www.ebay.com/itm/69-70-Honda-CB-750-CB750-Sandcast-KO-Stator-Cover-666-/371453893481

I have had the cover off and on and the whole thing apart like ten times trying to figure this all out. I appreciate the thoughts though.
 
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