Ammeter moving back and forth.Help!

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1963dartgt

1963dartgt

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So ive been having this problemfor about two weeks maybe driven the car twice since then. When i start it up it pegs full right for about 2 sec and settles back down to a little right of center mark then it starts to cycle from there to just the right of the first line. Its constant never goes farther in either direction but its constantly switching,it speeds up when with engine speed. The car is a 63 dart slant six only thing thats been done to it is, headlight relays and HEI ignition. Those were done about 6 months ago. It runs fantastic but i dont want to start a fire driving it like that. Thanks for the help.
 
Forgot to mention ive been through 4 known good voltage regs and two parts store alternators.
 
Start with the basics. Make sure fan belt isn't slipping and good ground from Engine to firewall. You don't say whether the regulator is electronic or the old style with points.
 
I got two grounds from engine to body, 3/4 of an inch deflection on the longets part of the belt,a ground from alt to body and from reg to battery neg. Its a solid state regulator.All the wires are good no burns and i spent about two hours cleaning grounds the other day with no change.
 
Take a reading of the voltage with the engine running and see if it fluctuates. I had a similar problem, it was a bad alternator.
 
Well i changed one alternator that was a no charge at all then the second one i put on there does the same thing as the first one. I let my pops borrow my voltmeter then i forgot about it and then he moved out of state . So i guess its time to buy another one.
 
Try reducing slack in the belt to about 1/2" and see if that helps. And is the belt in good shape. At this point I'm just trying to see if you overlooked something. I know when ever I had charging problems it was the regulator but it seems you covered that already.
 
If you have a harbor freight nearby get there coupon from the car magazines and get their VOM free. I have about 5 of them. Even if you have to buy it only costs about $5.00.
 
Belts brand new i change it every oil change just because its under warranty and i got a harbor freight about three miles away so ill go in the morning. I checked all my wires nothing is burned all my lights and turn signals and gauges work perfectly so i doubt its a wiring issue. The weather is finally getting nice and i just wanna drive it. Thanks for the help everyone ill check voltage in the morning and let you guys know how it goes.
 
These remanufactured parts aren't the best. Mine was only a few months old and was causing a stumble at high RPM. I changed everything else in the ignition system and didn't realize it was my alternator until it finally crapped the bed and stopped putting any voltage out. If you don't have a meter, bring it to a local auto parts store and have them test your battery and alternator.
 
I live in Camarillo where the Harbor Freight main warehouse is. I'm there all the time. If your interested, their infrared thermometer is on sale for $15. It is very useful. I've been measuring everything from ice cream to headers! Have fun shopping.
 
Well im an asst manager at autozone the only thing i dont buy there is alternators and power steering pumps. Ill pull it off and take it with me to work tomorrow on my way to harbor freight guess im taking the wifes mini van again tomorrow.
 
Check and clean your bulkhead connections this could be the issue
 
hade and still have the same issue with my car

went to a 1 wire alternator didnt help
redone the wire from bateri in the trunk to the starter relay
from bateri to the engine (ground)
from bateri to body (ground)
from the engine to the alternator (ground)

it help a bit but the moment I turn the lights on
the amp meter go back and forth
when the weather will be hotter ( -20*c) this morning so
I ll try a new ground wire to the light ground and see if it help

the amp meter is giving a study 15.2 volt
I know its pretty high and dont understand why

will follow your treads and see if I can find an answer for my problem!!!
 
Try jumping a wire direct from the battery + to the blue regulator wire at the regulator.
If it stabilizes this proves that the voltage the regulator normally see's is low because of a bad connection or has to go through too much old wiring to sense the correct voltage.
If the regulator always thinks the voltage is low it will try to compensate with more voltage causing the needle to jump.
That stupid connector that the alternator field wires go through at the rear passenger side of the engine was where most of my problems were.
Jumping the battery direct to the blue regulator voltage sense wire proved it.
 
1963dartgt said:
Forgot to mention ive been through 4 known good voltage regs and two parts store alternators.
Click to expand...

Check your wiring for any bare spots that may cause a short....

I kept going through alternators and regulators on my 69 Valaint... then found some melted wires behind the dash cluster where the wires got hot and melted the insulation and would periodically ground to the metal dash frame... I spent a week at my dad's during Christmas break repairing all the wires that melted together in the dash, then the main alternator and ignition wires under the hood and never replaced another alternator or regulator again in that car...

The ammeter would jump suddenly back and forth while driving when I had the short from road vibrations...
 
Well no time to get to it this morning had family time made some breakfast and played some ball with the kids. I got a day off tuesday gonna jump into it then unfortunatly thats the hottest day of the week so ill see how long i can stay ander the dash for. Thanks for the help everyone ill give everything a chance aslong as my twins arent to much of a handfull for the wife.
 
1963dartgt said:
Well no time to get to it this morning had family time made some breakfast and played some ball with the kids. I got a day off tuesday gonna jump into it then unfortunatly thats the hottest day of the week so ill see how long i can stay ander the dash for. Thanks for the help everyone ill give everything a chance aslong as my twins arent to much of a handfull for the wife.
Click to expand...
I know exactly what you mean. I have three boys, 7, 5, and 3. Hard to get on the car sometimes. Heading to the beach today. It's going to be over 80 degrees here today.
 
So i jumped the battery to the voltage reg and got a steady 14.5v out of it no jumping guess im gonna do some rewiring tomorrow thanks everyone.
 
this is the fix i used to stop mine from jumping all over the place. works perfectly after making this mod.
charging-system-relay-modification-jpg.1714962996.jpg
 
So i got my FSM out and started to look at the wiring diagram and realized wiring is not my strong point. I dont have ballast resistor the wires are tied together . Should i just replace the field and ignition wires under the hood or replace them going under the dash also.
 
1963dartgt said:
So i got my FSM out and started to look at the wiring diagram and realized wiring is not my strong point. I dont have ballast resistor the wires are tied together . Should i just replace the field and ignition wires under the hood or replace them going under the dash also.
Click to expand...

That may or may not do it.
The pic posted above is a good solution for it without having to rewire all of that.
The blue sense wire needs to see correct battery voltage, but we can't just connect the blue sense wire to the battery direct.
It needs to be disconnected from the battery when the car isn't on, so we use a relay to make that path from the sense wire to the battery short and able to carry good voltage to sense.
This is what the relay does.
 
Ok so i had two wires in and two wires out of the ballast. I unplugged those and soldered them together. If i wanted to add a relay would i just find the wire that goes to the regulator and wire that in with a relay.
 
Just take a jumper wire and connect one end to the positive battery terminal, start the car and then take the other end of the jumper wire and connect it to the blue wire on the regulator (leave the blue connected to the reg as it would normally be), now check the amp meter and see if it stabilized. If its stable and not jumping around then you can add the relay as above.
 
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