Multiple questions charging and electronic ignition

[Mopardreams]

Ok so I've tried searching for both answers to my questions but no lucky do I'm starting a new thread. A little background I have a 1970 roadrunner 383 auto. that was my dads he passed away when I was two so I can't ask him if he installed the Mallory electronic distributor. My aunt my have had it put in but not sure. So it has a Mallory electronic distributor it has the original style voltage regulator with blue and green wire still has a ballast resistor it has been like this for who knows how long and it works fine but is this correct? Or ok?

My second issue is that I replace the alternator with a NEW one not rebuilt new positive and negative batter cables, new voltage regulator and starter relay all to clean up and freshen up the engine bay some. I'm charging 13.40-14 at the battery but on the stud at the back of the alternator I'm at 15.40. Amp gauge runs around +5 or less driving around. Amp gauge was replace when my aunt had the car as well as wiring and wired through bulkhead connector. I have read some that say this is normal and others that say it's not please help. I also took it to a show last weekend about 30 min ride everything was fine.

 

[mopar 3 B]

If it works and you have know idea how things work leave well enough alone and enjoy.

 

[Yatzee]

Ok so I've tried searching for both answers to my questions but no lucky do I'm starting a new thread. A little background I have a 1970 roadrunner 383 auto. that was my dads he passed away when I was two so I can't ask him if he installed the Mallory electronic distributor. My aunt my have had it put in but not sure. So it has a Mallory electronic distributor it has the original style voltage regulator with blue and green wire still has a ballast resistor it has been like this for who knows how long and it works fine but is this correct? Or ok?

My second issue is that I replace the alternator with a NEW one not rebuilt new positive and negative batter cables, new voltage regulator and starter relay all to clean up and freshen up the engine bay some. I'm charging 13.40-14 at the battery but on the stud at the back of the alternator I'm at 15.40. Amp gauge runs around +5 or less driving around. Amp gauge was replace when my aunt had the car as well as wiring and wired through bulkhead connector. I have read some that say this is normal and others that say it's not please help. I also took it to a show last weekend about 30 min ride everything was fine.

15.4 volts is a bit high if it's constant. Usually after starting output should settle to around 14.2 volts constant especially if there's a lot of electrical load like cooling fan, fuel pump or other high draw equipment. Keep in mind that all alternators are not built to exact output across the board and yours may have a few extra loops of wire in the commutator. Just be careful where your sending all that juice, it should go directly to the battery so you can take advantage of 10ga wiring for that kind of output.

 

[Mopardreams]

If it works and you have know idea how things work leave well enough alone and enjoy.

I do have a understanding of how it works I'm just asking for input because some forums from this site and others say the 15+ is normal if it were a vehicle pulled in to the shop I work out it would be considered over charging.

 

[Mopardreams]

15.4 volts is a bit high if it's constant. Usually after starting output should settle to around 14.2 volts constant especially if there's a lot of electrical load like cooling fan, fuel pump or other high draw equipment. Keep in mind that all alternators are not built to exact output across the board and yours may have a few extra loops of wire in the commutator. Just be careful where your sending all that juice, it should go directly to the battery so you can take advantage of 10ga wiring for that kind of output.

The guy that owns a local starter alternator shop seems to think it's extra resistance in the original wiring. He said to put a jumper wire from the back of the alternator to the battery cable I did this temporary and just to see what happened and it went down to 15.10. I also bought another alternator to try to see if that's the problem but haven't tried it yet. And I don't want to order a engine wiring harness yet especially if I'm needing one modified for electronic ignition that's why I was hoping someone could answer the first question as well

 

[Wietse]

A new alternator might do exactly the same.
Your voltage regulator is the one commanding the alternator to charge or not.

With the engine idlng, measure the voltage on the input side of the voltage regulator.
So with your test meter on the - battery pole and the + on the input side of the regulator.
This voltage should be same or slightly lower (max 0.2 - 0.3 Volt) then the battery voltage at that moment.
If there is a big difference, say 0.6 Volt or so it means there is a lot of resistance in the circuit causing a voltage drop.

This voltage is a reference for your regulator to adjust the alternator to charge or not.
Check and see, this might cause a "over charge".

Edit: FYI, i think Classis Industries will sell engine harnesses modified for electronic ignitions, i remember seeing them for my model ('69 Coronet).
They are good harnesses and are color correct etc.

 

[Mopardreams]

A new alternator might do exactly the same.
Your voltage regulator is the one commanding the alternator to charge or not.

With the engine idlng, measure the voltage on the input side of the voltage regulator.
So with your test meter on the - battery pole and the + on the input side of the regulator.
This voltage should be same or slightly lower (max 0.2 - 0.3 Volt) then the battery voltage at that moment.
If there is a big difference, say 0.6 Volt or so it means there is a lot of resistance in the circuit causing a voltage drop.

This voltage is a reference for your regulator to adjust the alternator to charge or not.
Check and see, this might cause a "over charge".

Edit: FYI, i think Classis Industries will sell engine harnesses modified for electronic ignitions, i remember seeing them for my model ('69 Coronet).
They are good harnesses and are color correct etc.

I do think I have a voltage drop I'll check this weekend. On the note of the wiring harness I'm not sure if I should buy the electronic ignition one or the factory harness because everything is factory except for my distributor

 

[Billccm]

Per the SAE specs we use for mining (light) vehicles, the MAX voltage is 15.20V. This is measured at the battery.

You are measuring 14V at the battery, so I would assume you are in specification.

YES, you have identified a voltage drop from the alternator output to the battery terminal. To have a voltage drop current has to be flowing. I assume most of this current is charging the battery, but you can check various branches for current load by pulling fuses for accessories and lights. You may have some sort of current always flowing somewhere and the system is keeping up by showing a charge.

My point is I'm not so sure you have a problem. Test the voltage at the battery terminals with high beams on, blower fan at max, and hazard lights flashing. Voltage at the battery should be greater than 11.2, and preferably 13 to 13.8V.

Finally, keep in mind some batteries may have a soft internal leakage (like a soft short) and this will always present a load to the system and the battery will want charge current forever. You can test this with a battery charger that has an ammeter. Disconnect the negative terminal of the battery and connect the charger. It should show current for so many hours and eventually trail off to a trickle of less than 1A.

After saying all this, I'm in agreement with mopar 3 b that you probably have no issue.

Let us know how you make out.

 

[HALIFAXHOPS]

Most Mallories are aftermarket except the MP ones got a pic I can help you out with it.

 

[Mopardreams]

Per the SAE specs we use for mining (light) vehicles, the MAX voltage is 15.20V. This is measured at the battery.

You are measuring 14V at the battery, so I would assume you are in specification.

YES, you have identified a voltage drop from the alternator output to the battery terminal. To have a voltage drop current has to be flowing. I assume most of this current is charging the battery, but you can check various branches for current load by pulling fuses for accessories and lights. You may have some sort of current always flowing somewhere and the system is keeping up by showing a charge.

My point is I'm not so sure you have a problem. Test the voltage at the battery terminals with high beams on, blower fan at max, and hazard lights flashing. Voltage at the battery should be greater than 11.2, and preferably 13 to 13.8V.

Finally, keep in mind some batteries may have a soft internal leakage (like a soft short) and this will always present a load to the system and the battery will want charge current forever. You can test this with a battery charger that has an ammeter. Disconnect the negative terminal of the battery and connect the charger. It should show current for so many hours and eventually trail off to a trickle of less than 1A.

After saying all this, I'm in agreement with mopar 3 b that you probably have no issue.

Let us know how you make out.

I agree with you I don't think everything is fine just wanted some opinions

 

[Wietse]

It's not that you have a big over charge indeed.
With the test i described you can only make sure everything does what it supposed to do.

 

[Mopardreams]

this is the distributor i have mallory brand