1980 charging issues, green wire needs to be grounded for slap test to work

[ninosboombox]

Hi Guys,
Ive been rebuilding my 1980 yamaha 650 xs special 2, and have run into some problems, hoping the much smarter folks here can lend their expertise??

I have a new stator a new reg rectifier, new ignition switch, new stator, and a newer harness which was replaced in 2016 (all from mikes xs except the rotorm got that from ricks motorsports). so all pretty new, however I cannot get the slap test to work unless I ground the green wire coming out of the stator. I can either unplug the green wire and ground it to the frame, which creates the magnetic field and the slap test works (I did not start the bike with that wire grounded, only the key was on), or ground the green wire at the brush if i ground it w a wrench or screwdriver.

I do not want to start the bike just because I really am not an electrician and dont want to fry aynthing.

Also I am not sure if the wiring is going to the right place, If I match all of the wires by color the ignition button will not engage (also no slap test). I am also not sure if the old one was wired correctly either. I read that in the 79 and older you needed to unground the brushes, My problem seems like I need to ground the brushes (in order to make the magnetic field) so very confused. the old stator did not match the wire colors. heres how its wired in the connector plugs......

coming out of the harness.
the back 3 are from left to right.....

WHITE, WHITE, RED
front row of coming out of harnesss from left to right.
GREEN, BROWN, WHITE


connector coming from stator,
the back 3 are from left to right...
WHITE, WHITE, WHITE
front row coming out of stator, left to right.
GREEN, RED, GREY

I also read in the 79 and older that the red needed to be grounded, I did nto try grounding the red wire, only the green wire. (thats why I assumed the red matched up w the brown wire, but I dont know) Im running an 80 not a 79, so not sure if this is even valid on my model.

as I mentioned if I match all of the colors, when I turn the key only the brake light comes on, no buzz sound by the battery and does nothing while pushing in the ignition button.

The only light at the end of the tunnel is the behavior when I ground that green wire. Im really hoping I'm a big ol dummy and its something simple. would super appreciate any help. been through curlys posts and replaced basically the whole damn thing, should have just gotten the permanent magnet option, but didnt know I was going to place bit by bit. heeeeeeeeeeelp!! thx guys

 

[5twins]

I think you're mismatching plugs here. The harness plug you describe sounds more like the reg/rec plug. The alternator plug would not have two power wires (red and brown). The factory alternator harness plug has the 3 whites, a brown (switched power to inner brush), a green ( regulated ground from regulator to outer brush), and a light blue (neutral switch). On your new stator plug, the red is probably the "old" brown (to inner brush) and the gray is probably the "old" light blue (neutral switch).

 

[ninosboombox]

OK a bit more testing, I switched the red and green wires at the brushes to see if that would do anything, nope, it still has a successful slap test once I ground the green, It doesn't matter which position its in, which I assumed, but I'll try pixie dust at this point.

also, I tried grounding the red wire, it blows the main fuse.

thx guys.

 

[ninosboombox]

@5twins , thank you for the speedy reply!! You are correct it is the rec/reg plug, sorry bout that. After lookin at your post I got in there, I was incorrect on my first post about the red being in the back row w the other 2 white wires.

all white wires on both sides of the plugs are in the same row.

the green to green
Brown ( from reg/rev) to red
Light grey ( from reg/rev) to Dk grey

I tried swapping out all 3 positions of the green red and dk grey, but the only thing that performs the slap test is grounding that green wire.

With this configuration , the bike runs, but a no on the slap test. Will still tinker around.

5twins, thanks a ton!! Any other ideas?

 

[5twins]

Dealing with all aftermarket components can be difficult. Many times the wire colors used don't match the originals. If that's the case then you need to trace those off-color wires down to find out what they go to. You don't want to just start plugging stuff in or you might fry something. Sadly, that may be the case for you. You may have fried the voltage regulator portion of your combined reg/rec. Grounding the green wire full time is a way to test if the regulator is working, also the rotor and stator. Your rotor and stator appear to be working because you get magnetism when you ground the green wire. That points to the regulator as not working. It's supposed to be sending that ground out on the green wire to the outer brush. Check the connection to your reg/rec. Maybe some of the wires there are connected wrong.

 

[ninosboombox]

Will do!, I will also test the reg rec to make sure its good. Thank you!!