VCCA Home Forums TECHNICAL - 1945 AND NEWER 1949-1954 6 volt alternator conversion

Tired of voltage regulator and generator problems so just installed a new 6 volt alternator one wire system with built in regulator I bought from a very nice guy in Kansas.
Has anyone out there done this conversion? It was easy and straight forward and the voltage measured at the Battery is from 7.35 to 7.53 volts right where it should be.
Problem is the ammeter gauge in the car (1951 Chevrolet) only shows a "Discharge" but no charge?? I disconnected the three (3) wires from the regulator Bat. FLD. and Arm. because they have no where to go. Maybe the battery wire needs to be reinstalled???
For some reason the ammeter only shows the discharge and not a charge. With the lights off needle stays centered, low beams bring a quarter discharge, high beams 3/4 discharge. I don't want to short out anything experimenting and the system appears to be working properly just want to see that on the gauge.
Any ideas????
Appreciate any advice.
Mike

Did the conversions on both my 48 and 31 and just love the set-up. Yes, you need to hook the bat terminal up to output cable from alternator. Where have you got the output cable from alternator hooked up to now?? From the installation instructions, "The Batt wire from the old voltage regulator will connect to the 10/32" stud on back of the alternator. The rest of the wires were folded back and taped to the original harness for future generations."

Jim.

Hello and thx for responding so soon.
I presently have the Alternator output wire going to the starter solenoid post then to the battery. (just a junction)
So I thought maybe I should attach the Bat. wire from the old regulator up to something but what?
I also thought since the ammeter only shows a discharge that no current is through the ammeter from the alternator.
What corrects this? Duh......
Thanks
Mike

So I thought maybe I should attach the Bat. wire from the old regulator up to something but what?

i think jdv already answered your concern in his most recent post .....


"The Batt wire from the old voltage regulator will connect to the 10/32" stud on back of the alternator. The rest of the wires were folded back and taped to the original harness for future generations

Mike --

Not real good at explaining, but here is my take.

The old generator supplies the amount of current removed from the battery by all items on car being drawn from the battery through the external regulator mounted on firewall. The alternator does the same except the regulator is integral with the alternator.

The path of current supplied by the alternator, through the internal regulator, goes directly to the amp guage, through the amp guage to the ignition switch thence to the battery and all things electrical as needed when switch is turned on. With the switch off, there should be zero reading at amp guage. With the switch on, there should be a discharge shown until current is again sent through the circuit via the alternator being turned. Once the battery has the necessary voltage re-installed in battery as needed, the amp guage will again show zero as all things have balanced out.

So, you need to remove that current cable going from stud on back of alternator to starter terminal and butt splice it to the battery wire you have disconnected from the external regulator and all should be well. What worries me about the situation as it presently stands is the possibility of you burning up the alternator being hooked up as it is. Some alternators do not take kindly to the hot side going in the direction you presently have it hooked to. Keeping my fingers crossed for you.

You did not mention if the new alternator has to have the case grounded or if you have a DA plug going into the top of alternator which allows alternator to charge immediately at all rpm's or if you have to rev eng to get the regulator to excite. How have you wired it to shut down when ignition switch is turned off???

Jim.

Just a quick comment about my experience with an alternator vs a generator. The 28 Touring, which incidentally is powered by the engine built during the "School is in Session' was equipped with an alternator. Due to the specific alternator I used, it was necessary to rev the engine to a very high RPM to allow the alternator to "kick in". Once it had started producing power it would stay engaged down to a fast idle. If the engine was stopped for any reason it had to be "kick started" again.

So, if you plan to change over to an alternator, inquire as to the activation voltage. Select the lowest you can find.

If wired, as suggested above, you can get the ampmeter in the picture so you can tell if the alternator has "kicked in".

Thanks Ray --

That is why I asked him about type of alternator. Fifth Avenue sells what he calls a DA plug
that eliminates the need to get the alternator to "excite". Have had both styles on alt conversations and I sure like the ones that have that DA plug. I just finished restoring Dads 46 Case tractor and the 12v alternator I had on shelf for about 20 yrs or so was the type that had to be excited. I ordered the DA plug and that took care of the revving problem. They will charge immediately even at a slow idle which the ol' Case does.

Jim.

Thanks for your help guys. I used what I learn from others and it is fixed now and works perfectly (so far).
I was warned about running all the load through the ammeter now that I have a 60 amp charging device where I only had 35 amps before and that most likely the little ammeter would be burnt up as it wasn't designed for that.
So I ran a 10 ga wire from the alt. output terminal directly over to the starter solenoid post that the battery connects to and then......"tapped" the wire from the original old regulator to that wire near the old reg. which is still in place (for looks only). In this way the big "load" (we used to call it "juice") goes where it needs to go and the ammeter just show the direction + or -. That wire on my car was "hot" all the time anyway as the cut out in the voltage reg. stopped the current flow when off and I assume the reg. built in the alt. does the same thing since I see no current draw with the system off. BTW my single wire Alt. comes on-line as soon as engine starts with no need to rev up the engine. I like it very much and I noticed on a test drive last night for about an hour that soon after the cranking of the engine, that the ammeter shows just a small amount of charge as it should and the battery voltage is right where it is supposed to be, unlike my old generator that charged too much. My problem was always an over charging situation as opposed to an inop generator. I suggest this as a cure for either problem and thank you all for the time and info.
Mike

Good luck.
I've been running a 6v alternator in my 51 for years without ever having a problems. Gotta love the bright headlights at idle!!LOL