Battery staying at 16. Thought voltage regulator was bad so got another one.
Still having same issue. Anyone want to offer up next step for trouble shooting?
which regulator did you fit>> 310 or 340?
How are you measuring voltage? Do not trust the dashboard gauge…
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Multimeter. Bouncing between 14.5 and 16.
Does this answer your question?
Also, the middle male probe (-) when we were carefully making the connection the female end wire was pushing out of the plastic housing. We gently repositioned it. Not sure if that could be part of the issue, why I’m mentioning it.
While I have those with electrical knowledge on this thread, this relay appears to have had one of the prongs repaired previously.
What’s the process to accomplish this?
First of all, your field is grounded. Most likely a bad regulator, but my first question is whether the F and - wires are reversed at the regulator. There was a report a while ago that someone had received a new wiring harness with the regulator wires in some unexpected order. Also check that the connectors are properly insulated at both the regulator and alternator ends.
As for how the rivets are repaired, I have no clue where you would get those rivets and appropriate stamping dies. You could probably do a reasonable job with a punch, but you’d still need to find the rivet. But it would make more sense to buy a new relay. If you want to preserve the original “can”, you probacly can switch the old can to the new relay.
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that appears to be burnt
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Normal wiring for the 4TR control box> brown/purple to pos+ … black to neg- …brown/green to field, is that the setup you have?..is the regulator replacement new?
NOTE, brown/green field goes to alternator F- (field neg)
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Will confirm that setup when we are back at the shop. Was an OEM regulator. Thanks for the specs on wiring.
That relay was indeed “burned”. One of the shop guys attempted to soilder it back on. 
What Mike is saying is that the alternator output is high because its field terminal is connected to earth (more than it should be).
The way it works is this:-
The alternator is either fully “on” or fully “off”. It’s “on” when there is 12v across its field circuit (F+ and F- terminals). The 12v side (F+) of this is always hot and the other side (F-) gets grounded through its connection to the regulator.
The regulator’s job is to keep making and breaking the alternator’s field connection to earth so on average, the alternator puts out 14v, i.e. it repeatedly turns the alternator field circuit on and off in quick succession so the alternator is continuously being switched on and off.
If for any reason, you permanently connect that side of the alternator (F-) to earth, then the alternator just goes to full output and stays there.
The alternator (F-) is either getting shorted to ground or the regulator is so badly set that it is connecting the alternator’s F- to ground much more than it is supposed to. This is the problem that needs sorting.
kind regards
Marek
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Very helpful. Thank you!
When I had the same symptoms on my Series 2, the culprit was high resistance contacts on the alternator relay. If I turned on the headlights you could see them brighten and dim about twice per second. I temporarily eliminated the relay by linking the wires on the C1 and C2 terminals with a jumper wire (all done with the ignition off), and then started the engine. The alternator output settled to 14.2-14.3 volts as expected. Replacing the relay, or just cleaning up the contacts (I can’t remember which) solved the problem.
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Thank you David. We did a ton of relay and wire chasing when @Wiggles was here. Sure it’s something like that and actually wonder if my original voltage regulator was even bad.
We will try to solve this next visit to the shop.
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Confirmed that is the set up.
it looks like the 4TR control box which should be adjustable, i have the instructions & pic for that if you want it
Yes please Thank you.
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Older 4TR’s are adjustable, but later ones aren’t. Are you using an AGM battery?