Wiring Charging Light With Generator And Vr

Trying to get the AMP indicator light functioning. Delco Remy 35A generator with matching VR - not sure if its original Willys style or GM - but its all essentially the same I think?...The VR is 3 terminal - Batt, Gen/Arm and Fld. The 58 came with the later round cj style speedo cluster which has the AMP indicator light. 2 questions:

1) Is the AMP light/speedo set-up the same as in cj5. From what I can tell on the tiny wiring diagram in the FSM, the guage cluster is supposed to be just like the cj set-up, with 2 wire connections on the back of the bulb 'socket': one from key switched 12V and one from the VR. But, the current bulb socket is a single wire just like the standard background gauge lighting would be.
2) Where on the VR does the indicator light wire connect - Gen or Fld? As I understand the set-up, I think its goes to Fld as initially, before start up with switched 12V on, the Fld would be 0V and current would flow from the switch 12V through the light (light comes on)....but as the generator charges up, the field goes up and becomes near equal with switched 12V and thus current stops flowing (light goes out). I may be way off as well.....

thanks

 

So this is what confuses me....this diagram from the the FSM:


Based on this diagram, and from what I can understand, the charge light will be on anytime there is flow of current to or from the battery (whether its charging or discharging)....Or I don't really understand how the circuit works. IF this is the case, then the light will only be off if the battery is fully charged (or rather whenever the battery and regulator/generator have the same voltage). The light will come on anytime the battery and regulator have different voltages....And maybe that is all I need it to show....I guess I am used to the alternator version of this from the cj where the amp light tells you if the alternator is not producing voltage, but doesn't really tell you about voltage of the battery.

 

I don't know if this will help much but....I don't have the light hooked up, but I do have an ammeter and of course generator. When idling the generator doesn't charge and in this case the light would be on. If I give it a bit of gas the ammeter shows charging and this is when the light would go out.

 

In high school I had a '59 CJ5 and then a '61 wagon. They both had generators and the light and both did exactly what I described.

 

My cj set up with alternator does exactly as you describe as well...and that would be good for this one as well...just not sure how the FSM diagram would do that if the amp light signal wire is to the VR Batt terminal that is always hot 12V....or maybe that is the problem?

 

I won't say I understand it either, but the way the diagram shows it should work....at least I'd hope so. Isn't it the voltage difference like you said that makes the light be on or off?

 

Does your light come on when you turn the key to power (but not start)? For the alternator set up it does.

 

Light isn't hooked up at all on any of mine.....I only go through the ammeter. I am pretty sure I remember what I had in high school doing that but can't say I'm 100% certain they did, that was 51/52 years ago.

 

the charging system works perfect...it also has an ammeter that shows proper positive (charging battery) and negative (battery discharge) current....just trying to get the idiot light to function.

 

In that diagram the #5 "charge indicator" is an ammeter, not an idiot light.

The light socket does need to be a 2 wire type.

The idiot light would be wired between the ignition switch "ign" terminal & the regulator "arm" (armature) terminal.

When the ignition is on but the engine isn't started the battery voltage flows from the switch through the idiot light & the armature to ground.

At standstill the field would be full on & the light wouldn't illuminate if connected there & probably not much at all any other time, maybe a bit at idle with the lights off & after the battery recharges from starting

When the engine is running the genny is (hopefully - check that fan belt!) turning & producing charging voltage from the armature which blocks the current flow through the light.

 

Thanks Howard - nicely explained! I was about 80% of the way there at the beginning - although I still would struggle to explain how the field vs armature current and voltages interact (and if I had to guess I was guessing the fld terminal which would have been wrong). But then that charging diagram was just throwing me totally off - I did not think they would have an ammeter in the diagram for afaik neither the willys nor the cj (FSM had the same diagram) had an ammeter. I probably should know that diagram symbol was for an ammeter and not a bulb.... Awesome....now the hard part is going to be finding the switched ign 12V - with the steering swap and key switch inside the column, its not as obvious as the dash ignition switch. I might also have to poach the oil bulb socket which still has the 2-terminal set-up, but isn't wired in as there is a separate mechanical oil pressure gauge....wondering if PO got some of the bulb sockets mixed up at some point....need to check the others and maybe I'll find the missing 2-terminal amp bulb socket.

 

Yeah the diagram in the manual is a leftover from the CJ2/3.

The way the field operates is the regulator turns the power on & off to it so that the generator output (from the armature) *averages* the battery charging voltage- 13.8 or 14.5 depending on the vintage- (technically it's called pulse width modulation), When power is applied to the field the gennny is full on, when power is off the genny output drops. Note that most regulators do have a resister across the field relay contacts so that even when the relay is open some juice will flow through the field coil, I think this is to maintain the magnetization of the field magnets, i.e. self flashing.

Having the battery across the output of the regulator "smooths" the output so there's a nice steady voltage for lights not to flicker. If you read on in the manual one of the checks for regulator operation is to hook an old fashioned pair of high impedance headphones (steal them from your kid brother's crystal radio set ) to the field terminal & listen for the buzzing of the power going on/off.

 

So, now the question is, where do I find the a 2 terminal socket....
this looks like the best bet - although its not clear to me from the pic if the two wires come from the same terminal (and thus it wouldn't work) or different terminals?
Speedometer Cluster Bulb Socket with Double Wire Fits 55-71 Jeep & Willys (for 6 post plugs)