1968 Charger Voltage Regulator issue?!?

[91r/t]

Only question I have now is both the gauge from the factory dash and the aftermarket ammeter are reading around 20 on them both. Is that Amps? I checked the charging at the back post of alternator and its 14.8-15.1 but at battery where I believe it matters it is 13.1-13.7. All seems fine numbers wise but the gauges are high I think....Do I really care or should I worry or just leave them be?

 

[Billccm]

Well, I would assume the electric water pump would take some current. Perhaps you could do a current budget by checking specs? The battery may need some long time with a charge, also. Twenty amps is quite a bit, but your battery could be some of that, and the electric water pump another portion.

You do have a voltage drop from the alternator to the battery. This drop is the current through the wires, connectors, etc. Not knowing what is on the load and the path's resistance is hard to say if the ammeter is correct. I'd say for know call it fixed.

 

[Wietse]

The original meter in the dash reads amps indeed.
Pulling 20 is not uncommon to me, this might drop over time when the battery is fully charged.
I also had a big fight with my voltage regulator and over charging and after installing a new regulator i quite overlooked the fact that when starting the engine (several times for testing etc.) it pulls so much.
I was chasing a ghost when it was already repaired, all it needed is to charge the battery.
Leave the battery on a charge overnight and see what the voltages are.
Max. voltage on a battery i know of is 14+ Volt, if it is below that just drive a bit to charge the battery and see how the amp meter is.
I don't know if the previous owner wired all additional electrical components through the Amp meter, if that is the case it will always show higher then normal.
Another fact there if that is the case, all these amps are pulled through the Amp meter which causes a lot of restriction(heat) on them connections and they are not made for that.
This could cause shorts or a fire in a bad case, once i get a new underdash harness i will bypass the amp meter and connect them directly to prevent these problems.
You are losing 2.0 - 2.6 Volt between the alternator and battery, all that is due to restriction and that is turned into heat. (this path includes the amp meter in the dash)
I had similar issues and cleaning up and re-tightening all connections dropped that voltage loss on my system a fair bit so it might be worth doing for you as well.

Edit: You could use the voltage meter on the resistance function and measure resistance on certain sections of the wiring to identify the problem area's.
Fire wall connector and amp meter a known "hot" spot.

 

[91r/t]

Yea.....also maybe I will run another wire from the back of the alternator to the battery stud on the starter relay so most of the power goes that direction rather than through the amp gauge. I read that is a very wise modification to these systems, especially when you put a bigger alternator on to keep from overloading the amp gauge and wiring at the bulkhead.

 

[91r/t]

I believe a member on here NACHO-RT74 came up with this scenario....I am going to do the same but not go through the Ammeter. Just to the starter relay terminal with 8ga. wire.

 

[miller]

For what it's worth...I added the parallel wiring, exactly as shown in the above diagram, including through the stock ammeter, on my 64. With an 80 amp alternator, and stock mechanical VR...and it all works fine. I'll also add, I did not up the wiring size on the parallel wires, but matched them with the original 12 gauge.

 

[Wietse]

Once connecting a paralel wire on the amp gauge it will still work right?
But it will not show accurate as only partial amps are pulled through the meter.

Not sure if this is the right way to go to prevent burnt contacts on the amp meter.

 

[91r/t]

It isn't only preventing burnt contacts, but also giving the current somewhere elsewhere to go to prevent building heat up in the smaller wiring behind the dash and through the bulkhead. My connections are tight and everything is good in that aspect. I am just trying to prevent the melting of the bulkhead like so many experience. I am not looking for complete accuracy of the ammeter here as I can tell what its charging at with the Digital Voltmeter. I just want to keep the heat and resistance down in the factory harness.

 

[Wietse]

Yeah, the only thing you want to know if it is charging or not by the use of an Volt meter.
For my car i will stick to the original and rewire any electric add-ons separate on it's own circuits to prevent any issues.
The bulk head connector survived for nearly 50 years so once replaced for new it will do another 50 i guess.

 

[91r/t]

I definately agree with you on the own circuit. The fans I have running on their own relay and the waterpump is the big draw on the system. Like I said I inherited these issues so I am picking through them one by one

 

[mopwrd340]

I have seen batteries shorting out that will cause the volt meter to bounce back and fourth tricking the alternator to think it has a load on it .

 

[91r/t]

Yup used known good battery since the beginning but I definitely hear ya there!

 

[Wietse]

When in a case like this the battery has been "boiled" by overcharge would that leave permanent damage on the battery?
Mine has been boiling when i was driving around with overcharge before i found the issue.

 

[91r/t]

I grabbed a battery out of my Roadrunner so I knew it was good. Mine didn't get boiled because it never left the garage while i was fixing the problem. I suppose if you overcharge long enough you can damage the battery. I've had a battery left on the charger too long and boil over and it still was fine after i put a little water in it. It lasted for quite awhile after so I'd say it is a case by case deal.

 

[miller]

Once connecting a paralel wire on the amp gauge it will still work right?

Yes...as long as both wires are parallel, to and from the ammeter. That's the way it's shown in the diagram, and ammeter shows correct reading. The added parallel wire (same gauge) 'splits' the amps going through the two wires, giving the same results.

Two of my sons are electricians, one a master, and told me parallel wiring is used many times, when they wire up buildings, airport terminals, and the like. Not the same? Yeah, they are, at least in principal, splitting the amperage load between two wires, making the same path.

 

[Wietse]

Agree on splitting the load over 2 wires will lower the amps through each individual wire.
But both wires are still connected on the 2 studs on the amp meter, which still see the total load and on this connection itself (not the wires) there will still be resistance, building up heat.
You will see more resistance in a screwed connection/plug or any type of connector compared to a continues wire obviously so to me the amp meter it self is the danger.

But hey, if it works and there are no issues or dangers it should be ok.

 

[91r/t]

Not with my setup they won't both be connected. I am taking one wire from the back of alternator and going straight to the starter relay battery stud. That bypasses the ammeter with this 8 gauge wire. Therefore only the factory wiring is connected to the ammeter and its 2 studs. I am not following that diagram exactly but bypassing the ammeter studs with my 8 gauge wire, I think it will send more amperage through that vs the stock wiring. From what i know, electricity always picks the path of least resistance which would be that 8 gauge wire bypassing the ammeter and bulkhead vs. the stock wiring, and therefore taking the load off the factory stuff. Here I have edited the wiring diagram to show my setup.

 

[91r/t]

Agree on splitting the load over 2 wires will lower the amps through each individual wire.
But both wires are still connected on the 2 studs on the amp meter, which still see the total load and on this connection itself (not the wires) there will still be resistance, building up heat.
You will see more resistance in a screwed connection/plug or any type of connector compared to a continues wire obviously so to me the amp meter it self is the danger.

But hey, if it works and there are no issues or dangers it should be ok.

See above diagram as to what I am doing wiring wise.

 

[Wietse]

Yeah, that is the right way to do it.