1968 Charger Voltage Regulator issue?!?

[91r/t]

Ok let me try and explain my issue. I bought my buddies 68 Charger from his wife when he passed away a few months ago. The car has a 500cu in. big block and a 4 speed in it with electric waterpump, electric fans etc......Basically alot of crap to draw on the charging system. Most of the wiring is newer and he was good at wiring so I doubt there are hacked sections. I did alot of it with him soldered connections etc....I am having issues with it overcharging. The car has an electronic ignition on it from Mopar Performance and still has the single field wire type regulator. So I buy a new "electronic regulator" (circuit board vs internal contacts) that will work with the single field wire setup and I have nothing.....zero. Went from over charging to nothing. I just installed the ground strap on the firewall from the engine block so that's a fresh ground that I sanded etc. I check voltage at the ignition side of the blue wire on regulator and it is the same as the battery so that side of circuit is fine. What should the output be on the field side??? I am getting 15.9 -16.3 at the alternator stud on the back of it and 10.1 at the field terminal on the regulator with the original overcharging regulator. Should I try another regulator or is there something more happening??? I am beginning to run out of ideas. I put another regulator on today and it goes way overcharge again, but this one was the mechanical style and spiked all over. Is this just to much draw for the single field style to handle? Wondering if I should do a dual field alternator and newer regulator style and that'll fix it? Any advice I am all ears.....Oh also, the gauge in the car and the aftermarket gauge both work and are both showing an overcharge in the circuit. Heres a few pics of the car for attention and some help...

 

[slimt]

the regulator you refer to looks like the old style with a board inside.. correct? I had one of those that the store said would work..and it did not work.. I went back to the original style..

 

[91r/t]

Yea it is....problem is, I tried the original style tonight as well and it spiked like crazy and is still overcharging.

 

[91r/t]

Could there be something going on inside the alternator fooling the regulator into thinking it is putting out less than it is??? Bad connection at field wire or charging post?

 

[slimt]

Could there be something going on inside the alternator fooling the regulator into thinking it is putting out less than it is??? Bad connection at field wire or charging post?

Could very well be the alternator.. I actually changed out one of those as well due to just not charging.. yours could be doing opposite.. you have a ground wire? to the firewall?

 

[91r/t]

I have my engine to firewall ground wire in place yes.

 

[RT K_line]

I'm thinking that you need to do a total amp draw test. Most older single field alts put out at max 35 or so amps. You may have an overloaded charging system where it has to max out just to keep up. I switched to the square back alts that put out up to 65 amps and found a transistor type upgraded regulator. The only change is I ground the second field.

 

[91r/t]

If I buy the dual field alternator, I am going to upgrade to the newer style voltage regulator. That's a no brainer for me, as the expensive part of the upgrade is the alternator. I think that is the route I will probably take unless I hear something otherwise on here that can help my issue. Then atleast i know I have the better regulator and alt setup from the get go i guess.

 

[Ranger16]

Let me start by saying that electronics are NOT my strong point and most guys here have probably forgotten more than I know. That said, I'm not sure what regulator use used, but I have the same electrical ignition system as you do and had the same overcharging problem. I was advised to dump the old mechanical regulator and go with a Wells VR706. I did and I've had no problem since, for whatever that is worth.

 

[91r/t]

I believe I have one on the car......another thing I see now is there is a push button style starting button wired into the ignition circuit. I will be removing this tonight. I figure if its drawing any juice from the circuit, that can lead to fooling the regulator into thinking it needs to charge when in fact it doesn't through the blue signal wire.

 

[Billccm]

I know I am oversimplifying this, but if the field is grounded, the alternator is placing max charge into the system. The regulator grounds the field when charge is required.

By spikes do you mean that the mechanical regulator is pulsing max charge (on and off from none to max)? This would be a symptom of the alternator not sourcing the required current, or an overloaded condition, and maybe, just maybe too much AC from the alternator (bad diode).

I'd start with an alternator test. Maybe a parts store test, or ground the field yourself and see what the voltage output is with minimal load.

Let us know if you find more clues. Good Luck.

 

[Jackpot50]

Look at the wireing and make sure that it is correct with a charging loop to regulator.
Should come with regulator sounds like a wire is cut or off.
Blue with white tracer and green

 

[91r/t]

I should say more of a bouncing.....That was with the mechanical regulator so when I switched it to the electronic one like the wells V106 or whatever it is, it is a constant now just overcharging constantly. I am going to check the ignition signal wire when I get home and make sure that half of the circuit is good and not off from the exact battery voltage. if that is the case, then I am going to lean towards the alternator. What should the reading be at the field side of the voltage regulator with the car running at idle? The amount of charge the regulator is calling for? I am getting like 10 volts at that side of the regulator.

 

[91r/t]

Look at the wireing and make sure that it is correct with a charging loop to regulator.
Should come with regulator sounds like a wire is cut or off.
Blue with white tracer and green

View attachment 496084

That is for the 2 field wire regulator diagram....I am running the stocker 1 field regulator still. May update to the 2 down the road if I can't figure this out but same principle I got ya. Thanks!

 

[Billccm]

http://www.forabodiesonly.com/mopar/threads/alternator-voltage.181393/

 

[91r/t]

I'll go through that all tonight and see where I get.

 

[91r/t]

Checking voltage at the alternator stud I am at 15.4 but at the battery terminals I am at 13.4-13.8.....I believe I am in the ballpark now correct?

 

[Billccm]

Not sure exactly what the SAE specs are, but for light vehicles used in the mining industry (ie pick up trucks) the MIN is 12.6 and the MAX is 15.2V (operating spec). Typical is 13.8V, so I would say you are good.

 

[91r/t]

The ammeter in the dash and the aftermarket one is at 20 for a reading but I am going off the voltmeter I have which is more accurite.

 

[91r/t]

So here is what I find......tracing the blue wire with the tracer from the firewall block I get 12.5 volts at the wire block.....I check at the other end by voltage regulator signal wire and I get 11.5-11.7. Now that is suspect so I go and untape the wire.....TADA! Someone in the past life took the wire and skinned it and used it to power the electric choke. It must have been drawing on it hard enough to drop the voltage and then fool the regulator to charge to high.