• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Ammeter Quick Question and 95 AMP alternator question

That will fix the bulkhead connector issue but is the ammeter shunted for that alternator or the same part number?
I wondered that myself! I’d prefer to keep the stock amp gauge. Recommendations?
 
I do not have any good recommendations using stock parts, obviously that wiring scheme is better/safer than what you have as it takes all accessory load off the ammeter, all that is left is charge load. You could experiment with shunts like the leece Neville truck ammeter used so that the meter moves a little, it would be pretty safe then in my opinion.
 
That will fix the bulkhead connector issue but is the ammeter shunted for that alternator or the same part number? The way I see it the ammeter will not read when accessories are turned on in the car as the feed to them is spliced, and fed off of the standard fusible link. The circuit shown just isolates the ammeter, I bet it acts like the "dead" ammeter the later car had, in other words it only moves when the battery is discharged.
This post shows a version of the bypass and they loop the black alternator wire with the new wire on the ammeter black terminal. So in this case I guess the accessories are still fed but not sure. More to digest. Thanks for the help and making me think!!!
Some considerations about the charging and wiring upgrade and your worries about
 
Last edited:
Nothing wrong with wiring it like in the last link, I would eliminate that ammeter, but you want to keep it, so just be sure your ammeter has nice tight connections inside and eliminate the bulkhead issues. I cannot argue Nachos statement that the big alternators are not the issue, I ran the big 100 amp at idle leece-neville on a pickup for decades with stock wiring and never had an issue. Low voltage at idle increases amp draw and gets things hot!! If you ever see ammeter at max charge stop driving the car and pull a field wire to get the car home
There was a post on one of the dodge truck boards 10-15 years ago about upgrading the ammeter with copper tubing threaded on the studs so you could keep the head of the stud tight to the shunt THAT area of the gauge is where the ammeter starts to fail as these cars age. I think I found the link to that on a-bodies only. The only other advice I have is stay away from circuit breakers on the main charge line, use fusible links, example 6 gauge charge wire, 10 gauge fusible link, 4 sizes smaller than your wire is the general guide. You might ask Nacho what the upgraded ammeter is in his post that you linked.
 
... it takes all accessory load off the ammeter, all that is left is charge load...
To be clear, as originally designed, the ammeter should only have battery charge/discharge current flowing through it while in operation. Should not register any accessory loads at all if all loads, including added aftermarket loads, are correctly placed on the alternator side of the ammeter.

The factory “fleet by-pass” is a charge circuit bulkhead connector by-pass, ammeter is fully functional. The bulkhead Packard connectors are the weakest link in the original design.

BTW, there is a great deal of fairly recent charging system/ammeter threads/debates here on this site as well that has more than covered this particular subject.
 
Last edited:
To be clear, as originally designed, the ammeter should only have battery charge/discharge current flowing through it while in operation. Should not register any accessory loads at all if all loads, including added aftermarket loads, are correctly placed on the alternator side of the ammeter.

The factory “fleet by-pass” is a charge circuit bulkhead connector by-pass, ammeter is fully functional. The bulkhead Packard connectors are the weakest link in the original design.

BTW, there is a great deal of fairly recent charging system/ammeter threads/debates here on this site as well that has more than covered this particular subject.
I just wanted to reply and say, that in my case, someone who clearly admits that I know nothing about electronics other than shadetree mechanic, it was finally nice to find an actual diagram from Plymouth that documents how to do the bypass. There have been many debates back and forth with amazing points on both sides. But I'd never seen a diagram other than changes to the MAD diagram. So, for me, it is great to see something documented, from the factory, that for the most part, backs up the suggestions from everyone. Kind of like finding that actual book that tells you how to do it. Again, I am VERY grateful to everyone's help on this! The sad thing is -- I've actually found a two field 46 AMP that I might just use and be done with it. If I go EFI, fans, etc on my 73 RR that is still accumulating parts, I'm taking the gauges down to Redline for the voltmeter conversion and that will be that. But my 70 I really wanted to be stock since I love the carb feel, panic from overheating at stoplights, vapor lock, and all the fun I remember.
 
I never said or gave myself the credit for the upgrade, but just refresh and explained it.

on the manual doesn’t say to run parallel paths but use a thicker path I however suggest for the parallel path because:

-if still in good conditions the original path can be kept there and just reinforced with the parallel path, so don’t need to remove anything, just add.

-running a parallel path keeping the one still on car will allow to feed main splice down the harness tape from two legs instead one if required.
 
Last edited:
I just wanted to reply and say, that in my case, someone who clearly admits that I know nothing about electronics other than shadetree mechanic, it was finally nice to find an actual diagram from Plymouth that documents how to do the bypass. There have been many debates back and forth with amazing points on both sides. But I'd never seen a diagram other than changes to the MAD diagram. So, for me, it is great to see something documented, from the factory, that for the most part, backs up the suggestions from everyone. Kind of like finding that actual book that tells you how to do it. Again, I am VERY grateful to everyone's help on this! The sad thing is -- I've actually found a two field 46 AMP that I might just use and be done with it. If I go EFI, fans, etc on my 73 RR that is still accumulating parts, I'm taking the gauges down to Redline for the voltmeter conversion and that will be that. But my 70 I really wanted to be stock since I love the carb feel, panic from overheating at stoplights, vapor lock, and all the fun I remember.
The fleet/bulkhead by-pass as been diagramed/discussed here many times over the years, a few examples here.

I’ve been by-passing the charging bulkhead connections since my time at the dealers way back when.

No reason you can’t run added loads (including EFI) and retain the original ammeter as originally designed. All my current cars run 130amp TuffStuff alts, upsized wiring where needed, great deal of added aftermarket accessories, all sourcing their power on the alternator side of the fully functional ammeter. Running a Holley Sniper on the 400 in my Satellite.
 
Lots of the manufacturers quit using ammeters for a reason.

manufacturing cost. Voltmeters and idiot lights are cheaper.

on later years ammeter weren’t anymore a full load gauge but a remote reading through an external shunt, which were ever more expensive than the full load ones.
 
Last edited:
There was a post on one of the dodge truck boards 10-15 years ago about upgrading the ammeter with copper tubing threaded on the studs so you could keep the head of the stud tight to the shunt THAT area of the gauge is where the ammeter starts to fail as these cars age. I think I found the link to that on a-bodies only. The only other advice I have is stay away from circuit breakers on the main charge line, use fusible links, example 6 gauge charge wire, 10 gauge fusible link, 4 sizes smaller than your wire is the general guide. You might ask Nacho what the upgraded ammeter is in his post that you linked.

yes I have seen that same ammeter upgrade And it seems to be nice.

The continuous stress on the ammeters begins to get hot the contact area between gauge “shunt” and studs on ammeter which are installed just by pressure. The heat stretchs out the brass shunt and loose contact with studs, getting it loosen and creating resistance. BUT, when removing ammeter to check conditions, clean it up and soldering stud against the ”shunt” plate will assure a really good contact. There is a nice thread on another board what ilustrates this job. I have the pics around but I’m not posting right now from my PC.
 
Thanks again everyone! I’m admittedly a learner since I took off 25 years working on these. So if I frustrated or made someone mad, it was not my intent. I appreciate everyone’s input here!!!
 
yes I have seen that same ammeter upgrade And it seems to be nice.

The continuous stress on the ammeters begins to get hot the contact area between gauge “shunt” and studs on ammeter which are installed just by pressure. The heat stretchs out the brass shunt and loose contact with studs, getting it loosen and creating resistance. BUT, when removing ammeter to check conditions, clean it up and soldering stud against the ”shunt” plate will assure a really good contact. There is a nice thread on another board what ilustrates this job. I have the pics around but I’m not posting right now from my PC.
Some soldering pics here.
 
So aside from my general questions about my alternator output, today I changed the jets to get it to run a little more rich using an A/F meter and it is very happy under load. It's actually never run this well since I've owned it.

But, I was immediately reminded why I prefer to have an ammeter! When I started the car, it did go to max charge but then quickly went back down to around zero. Out driving, I spent most of my time looking at the A/F ratios, but when I looked at the ammeter, it was sitting just a little below zero, even under acceleration. The volt gauge under the dash seemed little high as well -- close to 15. When I got home, I turned on the lights and the meter jumped to the right but went back to same reading just below zero. Going to get out the multimeter tomorrow. But I would have never noticed something like this with just the voltmeter!
 
I never said or gave myself the credit for the upgrade, but just refresh and explained it.
I did not mean to imply your diagrams were from MAD. They were different and VERY helpful! I'm a techie by nature I need to see things in manuals so when I found the Fleet Diagrams, I got excited and wanted to share. :)
 
Last edited:
So aside from my general questions about my alternator output, today I changed the jets to get it to run a little more rich using an A/F meter and it is very happy under load. It's actually never run this well since I've owned it.

But, I was immediately reminded why I prefer to have an ammeter! When I started the car, it did go to max charge but then quickly went back down to around zero. Out driving, I spent most of my time looking at the A/F ratios, but when I looked at the ammeter, it was sitting just a little below zero, even under acceleration. The volt gauge under the dash seemed little high as well -- close to 15. When I got home, I turned on the lights and the meter jumped to the right but went back to same reading just below zero. Going to get out the multimeter tomorrow. But I would have never noticed something like this with just the voltmeter!
It sounds like you have made a choice, you also now know the big trouble spots, bulkhead and ammeter studs that get loose, many ways to fix those issues. The voltmeter just told you more than the ammeter...15 volts is too high. At normal engine temperature it should be 14.25. Stock mopar 100 amp alternator voltage regulators, are not the same as the 65 amp and lower regulators, charge at around 14.75 cold, 14.25 at 70- 80 degree ambient temp and 13.8 or less on a 100 degree day. Some aftermarket regulators run over 15 volts, some do not temperature compensate, harder on the battery, and the wiring. The voltmeter will also tell you when the alternator or regulator fails by showing 16 volts or more, and shows failure by showing low voltage. An adjustable voltage regulator is available, but the one I used did not temperature compensate, just allowed you to set the voltage. Some of the post in various links are pretty funny as they say the factory went to voltmeters because it was cheaper, I doubt that. Modern charging systems measure the temperature of the battery, and outside temp, maybe even other things, and control it with a computer with the battery hooked directly to the alternator stud. I guarantee you was not cheaper to do that, just way smarter.
 
It sounds like you have made a choice, you also now know the big trouble spots, bulkhead and ammeter studs that get loose, many ways to fix those issues. The voltmeter just told you more than the ammeter...15 volts is too high. At normal engine temperature it should be 14.25. Stock mopar 100 amp alternator voltage regulators, are not the same as the 65 amp and lower regulators, charge at around 14.75 cold, 14.25 at 70- 80 degree ambient temp and 13.8 or less on a 100 degree day. Some aftermarket regulators run over 15 volts, some do not temperature compensate, harder on the battery, and the wiring. The voltmeter will also tell you when the alternator or regulator fails by showing 16 volts or more, and shows failure by showing low voltage. An adjustable voltage regulator is available, but the one I used did not temperature compensate, just allowed you to set the voltage. Some of the post in various links are pretty funny as they say the factory went to voltmeters because it was cheaper, I doubt that. Modern charging systems measure the temperature of the battery, and outside temp, maybe even other things, and control it with a computer with the battery hooked directly to the alternator stud. I guarantee you was not cheaper to do that, just way smarter.
Thanks! I love this place and all of the help!!! It wasn’t quite at 15 or higher on the voltmeter so I would have not really noticed with the voltmeter other than to keep an eye on it. But the discharge on the ammeter under acceleration made it more obvious.
 
Last edited:
An adjustable voltage regulator is available, but the one I used did not temperature compensate, just allowed you to set the voltage.
I don't mean to highjack the OP's thread, but hope to add info to it. I have seen the adjustable units for 1970 and later style regulators, but not for 1969 and older. Do you know of any adjustable unit made that will work with the older 2 wire regulators?
 
I don't mean to highjack the OP's thread, but hope to add info to it. I have seen the adjustable units for 1970 and later style regulators, but not for 1969 and older. Do you know of any adjustable unit made that will work with the older 2 wire regulators?
Mopar did have an adjustable 2-wire voltage regulator, used for police cars and taxi cabs.. Often they are listed on E-bagger..
Here is a link to 1...

Just my $0.02...

 
Last edited:
So, in regard to my discharge post a few posts ago -- I went out to the car this morning and I noticed that the ammeter was sitting on the slight left of zero that I thought was the discharge yesterday.

So, I made sure that my battery was disconnected, and it was. So, I connected the battery, turned on the lights and it discharged as expected. So, I turned everything off, and it went back to the just left of zero position. I disconnected the battery and it sat there to the left of zero in the same spot as where it seemed to be discharging when I drove it yesterday! Just amazing! I replaced the gauges all last year with OER since mine had decals from a PO and looked wrong.

I guess the initial slapping to the right when the car was started with the 95 AMP alt must have bent the needle or something. I checked most everything else quickly and battery is ok, alt, so I guess it was just the initial issue that made me create this thread. I know it was zero when I installed it since I have a bunch of pics. If anything, here is a great argument for not keeping the ammeter (or rebuilding an original vs OER) or you'll bend it with a high output alternator. :)

Wondering if a higher rated ammeter would have prevented this (as in Nacho's design on the other forum). But for now, I am going to keep an eye on things and just enjoy the car. It is very happy with the new jets/rods I put in yesterday, so I'll pick this back up after I've done the bypass. Again, thanks everyone for the help!!!
 
Auto Transport Service
Back
Top