1968 Dodge Polara, 383 Alternator issues....

[mccombs1982]

Ok, I am currently lost. I have been working on a 1968 dodge polara and the alternator that is on it is a double FLD alternator and the standard voltage regulator i do believe. in 1968 the standard generator had a single pole fld. so this generator in place is the double and one side of the fld has been grounded and the other connected to the regulator. once vehicle is running the alternator is pushing out 25 volts. and no the 25 volts is not making it to the battery, the other alternator burned the charging wire that goes to the fuse block.

What really has me stumped is that the charging wire goes the accessory side of the fuse block, and i have no idea why, why not wire it to the battery???

if hot wire off alternator feeds into the fuse block what role does the ballast ( i hope thats the right name for it ) play in the vehicle, there are wires running to it but not sure where they go to..... have not decided to go that deep into it yet.

If anyone has any ideas please feel free to inform me as to where im going wrong or if this is a normal issue.... thank you for your time

[Nacho-RT74]

ok, first you need to know the alternator output wire runs right directly to ammeter. Between the bulkhead and ammeter there is a splice what also feeds fusebox BATT SIDE ( becoming red ), Ign switch ( becoming red ), headlights switch.

After the main wire section gets the ammeter, wire becomes red from the ammeter other stud, to bulkhead, directly without splice and becomes on to a fuse link up to starter relay on engine bay. Then a wire from starter relay stud to batt.

If something of that tracing is lost or some wire is loosen, never will get the batt, or barelly will feed the batt back.

Acc section shoulg get power ONLY with ign key in acc.

The splice in to wire running to ammeter feeds ign switch and when you put ign on RUN, then blue wire up to ballast is being feeded, same as blue wire up to regulator. Ballast is a thermostatic power source to ign coil. More heat into engine bay, less power to coil from ballast, due less power needed to burnt gas being warm.

25 volts from alt is if you ask me definitelly a shorted alternator inside. 25 volts from alt doesn't need is effective charge to car/batt, because what charges the batt is amperage, not voltage, even they normally are proportional relationed. Normally doesn't need ALLWAYS AND EFFECTIVELY.

[mccombs1982]

The alternator is new and testing shows ok. So why would it be showing 25 volts?

[Nacho-RT74]

ok, I just can talk from my experience. I got a perfect alt tested on bench but somehow when moving and isntalling got a short inside... APPARENTLY rotor was shorting somehow ( maybe the vent fins ) with stator leads at diodes bank terminals for a while spining on car. Had to bend a little bit the eyelet terminals.

when got that, I got 24 volts but discharge at iddle on ammeter. just revving up was getting charge, and still 24 volts.


just an idea.

then about the rest, be sure everything is right wired. Mymopar.com website has diagrams at TOOLS section ( I can't open those right now because I'm getting a malware alert from brwonser alert system at mymopar but lot of ppl is able to open the diagrams )

[Charger RT]

Hello I am new around here and this is my 1st post. But one of my favorite subjects. I would guess if you take a voltage reading with the engine off on the stud on the back of the alternator where you are reading 24 volts the reading would be 0. It should be reading battery voltage. You said the alternator burned up some stuff and it seems open from the reading. If the circuit is open the regulator can not see it charge and will run the field wide open. The will cause a very high output voltage that ends up going nowhere.

They did run way to much wire on these alternator wires. My charger has burned the plug at the fire wall twice. The last time I repaired it I added a second charge wire straight to the battery. The amp meter will not work this way but it charges better.
Tim

[Nacho-RT74]

They did run way to much wire on these alternator wires. My charger has burned the plug at the fire wall twice. The last time I repaired it I added a second charge wire straight to the battery. The amp meter will not work this way but it charges better.
Tim

http://www.dodgecharger.com/forum/index.php/topic,33574.0.html



and welcome

[Nacho-RT74]

I would guess if you take a voltage reading with the engine off on the stud on the back of the alternator where you are reading 24 volts the reading would be 0. It should be reading battery voltage.

so you will get 12 volts not 0

You said the alternator burned up some stuff and it seems open from the reading. If the circuit is open the regulator can not see it charge and will run the field wide open. The will cause a very high output voltage that ends up going nowhere.

if car is starting up, you are getting voltage at blue wire to regulator, because blue wire is what feeds ballast so then the coil. Diff stuff is if regulator is not giving output to alt field input.

If you don't get field power at alt brush you won't get output on anyway, no matter if low or high ouput you need input at alt field to get somekind of output. the fact is he is getting power at alt field, no matter if wrong signal or good signal. You can't get power if you don't get magnetic fields inside alt.

Neither you will get "power going to nowhere" because if there is output is because car is demanding power, controled by regulator. If is not the batt who is getting the juice, is ANYTHING on car demanding the power INCLUDING IGNITION.

Then if alternator is not able to give the juice, is the batt who is feeding the car demand, so batt discharges and thats the moment you get Discharge reading on ammeter.

[mccombs1982]

It turns out that the wire to the ammeter was burned up, and the wire leading from ammeter back to battery was burned up as well. Both at the plug on firewall, I feel so dumb cause i didnt see it earlier. and as a precaution we ended up changing the regulator as well, thanks everyone for your efforts i have gained a lot of knowledge from here and other sources......

[Charger RT]

glad you found it. so the circuit was open. that 24 volts is a good clue to that.
I find the best way to find something you are looking for is to ask for help looking and as soon as you ask you see what you have been looking for.
Tim