Need help car charging at 15.2 volts

[keith88]

Hi,need some advice from someone who know about a charging system in a 69 charger. A month ago I bought a USB adapter with a volt meter in it that's when i found out my volts were high...it said 15.5 I bought a new external regulator and it was saying the same thing. My alternator wasn't the best (on the car when i got it) so i bought a new one still no change, so I bought a solid state regulator and it said the same thing (15.5)so I did some research  and sounded like it might have been a grounding issue and ran a ground wire  from the regulator to the ground that connects the engine to the body I also cleaned the other grounds where i could find them popped off the bulkhead connector made sure that was good to, started the car same reading. So i bought a multi-meter checked it with that it was a little lower but not enough to make a difference at 15.2
Now I'm not sure how long its been like this because the amp meter in the car shows normal and if I'm right this reading is a bit high but I have never blown a bulb or even felt the battery get warm.    What should I look at next?

[John_Kunkel]

With the engine running, take your multimeter and check the voltage at the battery terminals,  then measure the voltage at the IGN terminal of your regulator; this is the voltage that the regulator bases its output on, if the voltage is low at the IGN terminal the regulator will crank up the voltage to try to raise the system voltage.

If the voltage at the IGN terminal reads lower than the measured battery voltage, check all the connections at the bulkhead connector and the ign switch.

[keith88]

I have 12.6 at the battery, tried the ign side of the reg to got 12.5 with key off.

[Gold Rush]

Like John said...  With the engine running. 

[keith88]

OK with the car running on the IGN side I'm getting 14.6 volts on the field side looks like 2.4 or so volts. At the battery 15 volts.

[keith88]

Just took the car for a 20 min ride its now 14.8/.9 battery not hot... charge on the high side tho.

[b5blue]

12.6 is a bit weak at the battery, possibly the system is just trying to pump it up and that's what your seeing. I'd take the car to Advance Auto Parts and have it checked. They do it for free and you get a print out of many test areas. (Plus they love messing with cool old rides so it's kinda fun.)  

[keith88]

That was with the car not running its 14.8 with it running.

[b5blue]

Right. Have it checked. 

[Gold Rush]

OK with the car running on the IGN side I'm getting 14.6 volts on the field side looks like 2.4 or so volts. At the battery 15 volts.

It seems to me that your regulator should have picked up on the 14.6 as too high and brought the alternator back to near 13.8 volts.  I have to be honest that I don't know what the field side should be under normal conditions.  Maybe it is trying to get the alternator lower but getting no correction.

I agree that a trip to Advance Auto might be wise.  Sure can't hurt.   

[b5blue]

here:  https://www.autobatteries.com/en-us/battery-testing-and-maintenance/car-battery-voltage-and-testing

[keith88]

I read the link, i did the test with the lights on already and running the radio charge stays the same at 14.8 With the brake light on goes to14.5 and if i hit the general lee horn its 14.2 that pulls a bunch than it will go back to 14.8.   

[John_Kunkel]

Try a different battery and see if the readings stay the same.

[c00nhunterjoe]

12.6 static is fine. I currently have a dead cell in mine (11. and do not have charging system issues.
If you are getting 14.6 at the ign port on the regualtor but 15+ at the battery, you have voltage drop problem. What is the output at the alt terminal vs the ign port on the regulator? Then what does it do with the reg disconnected. Then with it full fielded.

[keith88]

As of now Im getting 14.8 /14.9  at the battery after i redid the connection for the IGN side to the reg.

[c00nhunterjoe]

Still too high imo. Have you run the said tests? And also add disconnecting the battery and seeing the voltage while running as well. What does it charge at say 2500 rpm?

[keith88]

I haven't run the test yet was going to do that after work today but I can tell you is 14.8 at 2500 rpm

[keith88]

Ok got home did some more testing "at the alt terminal' had 15.2 When i 1st started the car today I was getting 15.1 seeing that I decided to put back in the new mechanical regulator in( had one of those solid state ones that look stock) just to see what I got and  I was getting 14.3 going to leave it in and start it in a couple hour see what happens.

[c00nhunterjoe]

If the voltages change with each regulator you swap- that tells you your problem is quality control in the regulators.

[keith88]

Yea that the truth..lucky the solid state one has a warranty on it ,they will be hearing from me over the next few days. I did go back out and start it an hour later and it was still 14.3. I'm going to take it to work Wed it going to be a nice day here see how it goes. Plan is to put it away this weekend for the winter.

[c00nhunterjoe]

They wont care. Customer service is a thing of the past. Probably made in china. I never had any luck with the "stock" style regulators. My best luck was the blue mp race regulator. Held up the longest. Since then i went with an internal regulated cs130 and never looked back. Cleaner engine bay, less wiring, more amps at peak and idle, less headaches, lifetime warranty if needed.

I can run all lights, elec fuel pump, msd 7al2 race box, elec water pump, elec fans, and still hold 14 volts at idle.

[keith88]

I payed extra for the one made in America that had a warranty well see how that goes. But I might do what you did in a few years.

[keith88]

Ok I took it to work Wed s and drove it about 60 miles that day but it went a little strange It stays at 14.3 until I got on the highway where it slowly made its way to 15.2 and stayed there till i got back under 2000 rmp where it went to 14.3 again hangs around there around town driving. any time i start it its 14.3 WTF battery never felt hot  ran fine other wise..Confused!!

[c00nhunterjoe]

Regulator

[John_Kunkel]

Try a different battery.