Solid State Recitfier

Ok so I have a 1976 motor that I am using a solid state rectifier/regulator with my stock points system. The first one would not charge battery. Jumped green wire from alt to ground and voltage increased with rpms. So I bought new rectifier and went over wiring for the umpteenth time and had same result. Voltage at battery remained stable even with increased rpms but with green wire to ground voltage increased. The old unit did not get hot during test how ever new unit got really hot. New unit bad? Engine runs fine and starts great. Have not had on road yet trying to get this issue worked out. Should I just buy a new unit or is there something else I may be missing.

You may want to review and double-check how your charging system is set up.
Originally, your '76 system supplied regulated power to the rotor using the green wire.



If you're now using a MikesXS solid-state regulator/rectifier, like this:



And followed these wiring instructions:



Then, you need to determine just what that green wire is. Grounding it on a stock 70-79 system will blow a fuse...

What rec/reg did you use? Where did you get it from? New? Used? PMA or stock? Pics please.

TwoManyXS1Bs said:

You may want to review and double-check how your charging system is set up.
Originally, your '76 system supplied regulated power to the rotor using the green wire.

View attachment 48046

If you're now using a MikesXS solid-state regulator/rectifier, like this:

And followed these wiring instructions:

View attachment 48047

Then, you need to determine just what that green wire is. Grounding it on a stock 70-79 system will blow a fuse...

Click to expand...

I have the green going to one brush and I disconnected it then took it to ground.Just for a moment to test for increased voltage with increased rpms. The red wire feeds the points and the battery through a switch. I am not using mikes but a unit that is supposed to be for a points system.

azman857 said:

What rec/reg did you use? Where did you get it from? New? Used? PMA or stock? Pics please.

Click to expand...

New unit from company on ebay. Stock points system.

The way that you're describing the response of grounding the green wire, and the wire coloring on your rec/reg pic, gives me the impression that your charging is configured as a 80-up type (which was not a points system), with brown supplying power to the rotor, and green is the regulated ground for the rotor, and the brushes are configured as such.

Is this true?

TwoManyXS1Bs said:

The way that you're describing the response of grounding the green wire, and the wire coloring on your rec/reg pic, gives me the impression that your charging is configured as a 80-up type (which was not a points system), with brown supplying power to the rotor, and green is the regulated ground for the rotor, and the brushes are configured as such.

Is this true?

Click to expand...

Here is the diagram I used inserting the solid state rec/reg in place of the split unit.

Okay, that's the 80-up combined rec/reg schematic. Did you use an 80-up alternator or do the brush mod for this reconfiguration?

Relevant info can be found by googlebox searching for: "nylon screw" ...

Ungroud brushes otherwise stock

Well then, I'm leaning toward a bad reg/rec module. Were there any instructions? Does the case need to be solidly grounded?

Had grounded no change I am thinking bad unit also just hoping for something else. Thanks

Which brush is positive right or left? When I check with meter running I have battery voltage on right and less on left.

On both brush configurations, the outer brush is the regulated brush. The inner brush is either grounded or full-powered.

What voltage did your battery go up to when you ran the green to ground?

On your brushes, What color are the wires?
The points bikes had a green wire and a black wire. They also used brushes with two different mounting straps.
On the 80 up they used a green wire and a brown wire. Both brushes use the same style of mounting strap.
On the points bikes, power is sent to the brushes on the green wire from the regulator. Then grounds on the black wire and the mounting strap.
On the 80 up bikes power is sent to the brushes on the brown wire, the green wire goes to the regulator, the reg grounds the brushes.
You can't use the wrong reg/rec on either system.
Figure out which stator/brushes you have, then we can help get things working.
I'll post up pics of the brushes. The first two pics are the points brushes and brush holder, the last two Are the 80 up brushes and holder.
Leo

My motor is a 76 with green wire to the outside brush and black to the inside brush. Wiring from scratch using wiring drawing posted above. I have the brush holders in the top picture.

Using the wiring I posted above I ungrounded brushes and my brown connects to the black from my brush. Leo are you saying my black should go to ground with a solid state unit?

Solid state replacement reg/recs can be set up two ways. One for the 80 up bikes. One for the 70-79 bikes.
The pic of the one you have indicates it is for the 70-79 bikes. It has two plugs on it.
The 80 up have one plug.
On the 70-79 regulator, it uses the brown wire as a voltage sensing wire as well as a power source. When you first turn on the key the reg reads low voltage, at this point it sends full battery voltage out on the green wire to the positive brush. From this brush through the rotor, out the other brush to ground. It grounds through the metal strap to the stator housing, engine, frame, battery. It also grounds through the black wire to the harness.
Your reg/rec should work this way. So just wire it that way.
It has two plugs that just plug into a stock wiring harness. It looks like it may be wired wrong. The one small plug that goes to the regulator plug of the stock wiring should have three wires, green brown, black. Your pic shows two.
The other plug with the three whites should have 4 wires, 3 white, one red.
Seeing as your building your own harness, hook the 3 whites of the reg/rec to the 3 whites of the stator. The red wire to battery positive, black to ground. This wires the rectifier half of the reg/rec.
The brown wire goes to power after the key switch, Green to the positive brush. I would also run a black wire from the case of the reg/rec to ground. This wires the regulator half of the reg/rec.
If your reg/rec is for the early system then this should make it work. No need to unground the brush at the stator. That only applies if you are trying to run the 80 style reg/rec.
The 80 up reg/rec uses the brown wire for voltage sensing only.
The green wire from the brush to the reg/rec is a ground wire.
The positive brush gets power from a brown wire. When the reg/rec senses low voltage it grounds the green wire.
The 70-79 controls the power flow through the rotor before the rotor. The 80 controls the power flow after the rotor.
Leo

Ok so out to the garage later and on to making a few changes and see if we can get this rascal going. Thanks

So out to the garage I went. I replaced the nylon screws with the metal ones. I disconnected the black brush wire coming form the alt. and left green to the green brush and connected brown to power after switch. Now what do I connect the black wire from the other brush to? I had it running with over 15 volts at battery. The rectifier is getting very hot but that may be normal. I only let it run for about 5 mins.