Charging System Issue - Likely Regulator

[Port]

I have Pamco ignition system with the EAdvance installed on my '81 heritage special with the stock solid state regulator/rectifier and im having a bit of trouble with my charging system.

I followed Curly's charging system troubleshooting guide that is reposted all over the place and got to point 3 and shorted out the green wire to the regulator rectifier and got these results.

Curly's charging system troubleshooting guide step 3:
"On the solid state regulator models all you need to do is locate the green wire at the regulator plug and make a jump from it to ground. That bypasses the regulator and allows full battery current to flow through the brushes out of the rotor through the green wire to ground. That causes the rotor to make a stronger magnetic field which in turn causes more current to flow in the stator. If your battery terminal charge voltage jumps up to 14.5VDC when you rev the engine then the regulator or the ground connection for the regulator is your problem."

Measured across battery terminals:
Key-off - 12.3v
Key-on - 11.8v
Idle - 12.4v
3k RPM - 12.8v
3k Green wire on regulator jumped to ground - started off at 13.5v and built up to 16.5v so I killed it

I don't think its the ground to the regulator. Any way of checking the functionality of the regulator before replacing it. If i need to replace it, any advice on what to replace it with? Im considering swapping over to a permanent magnet system. Might have cooked the regulator as it did not have good airflow where it was mounted.

I think that it might be related but my blinker is also behaving strangely and it might provide relevant information:
- Bike off with a fully charged battery blinker works fine
- Beginning of a ride with a fully charged battery blinker works fine
- After a bit of riding, I might get one or a few blinks and then the flashing unit no longer triggers
- At high RPM I might get a few solid blinks but as a slow the RPM the blinker will go but then if a pull in the clutch the blinking will come back
- After a bit more riding, the blinker does not function at all
- Even if the flashing unit is not operating, pressing the blinker cancelation bottom will cause a single "click" of the flasher unit

 

[gggGary]

Yes your tests point at the voltage regulator as the problem.
The turn signal malfunctions are consistent with low voltage in the system.
If you still had a TCI ignition you would have been walking home.

 

[Jim]

If i need to replace it, any advice on what to replace it with?

Agree with Gary. Looks like you need a new regulator. Look for a VR-794 on Ebay. They can usually be had for less than 20 bucks. Here's a link to my less than $30 reg/rec. The link to the Ebay regulator is in that thread.

 

[Port]

Agree with Gary. Looks like you need a new regulator. Look for a VR-794 on Ebay. They can usually be had for less than 20 bucks. Here's a link to my less than $30 reg/rec. The link to the Ebay regulator is in that thread.

Looking at the link that you posted I notice that there is not that says that the regulator ground is made through the mounting hardware. Is this the case with the stock RR? If not, how is the grounding connection made? I didn't see a ground on the wiring schematic but I might just be missing it.

Additionally, where is the stock mounting location for the RR? It was just stuffed in the toolbox cavity when i got the bike and i have never been able to figure out where it is supposed to be mounted.

 

[Jim]

.....the regulator ground is made through the mounting hardware. Is this the case with the stock RR?

Yes.

Additionally, where is the stock mounting location for the RR?

On the downtube, aft side, just above the swingarm pivot.

 

[Port]

Yes.

On the downtube, aft side, just above the swingarm pivot.

Well then, I may not need to replace my RR. I'll update the thread tomorrow. Thank you very much for your help.

 

[5twins]

Actually, the stock reg/rec has a ground wire in the harness that runs to it. It is one ground wire and gets shared by both the reg and the rec. The aftermarket Fiat regulator Jim linked to grounds through it's case and mount.

 

[gggGary]

Won't hurt to confirm engine/chassis/battery ground connections. Not everyone understands the importance of ground paths. Hint the bolted engine mounts aren't enough. The battery ground strap rotting is a common issue. I've replaced dozens of them. Years ago I found a package of ground straps at a local salvage store. They were perfect just had to drill out one of the lugs a little, the bundle of them must have had 20 straps, they are all gone now.