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the battery light on the dash glows very faintly if at highway speed with the lights on ,I can see it at night or predawn on my commute to work when the lights are on ,its just barley barley illuminated ,
its not the bright glow as when the ignition is on and the cars not running ,cant even tell during the day . I THINK it gets very slightly brighter when I hit the turn signal .I dont notice it at slower speeds
Does this mean the generators not charging enoughat speed ,or that there is an excessive draw somewhere thats somehow velocity related or rpm related ?
Is the pulley on the generator the wrong size such that it spinns to fast ?
If I was to check the generator with a voltmeter to see if its charging does anyone know what do I hook the little leads to and set it at ?

Some instructions are in the electrical section of SM, but IMHO there is not a whole lot you can check without having some test equipment with more capacity than the typical volt-ohmmeter. It also helps to have an understanding of how things interact because voltage and current adjustments are dependent. Change one and it affects the other so messing one up can cause a no charge condition or seriously do damage.

Again, about the only thing you can check reliably with a home voltmeter is the voltage output. It sounds as if that is OK since the red light does go out. After things are warmed up, use the voltmeter to measure across the battery posts. A fully charged battery will read right around 6.3 volts just sitting. After measuring that, start the engine and run at a fast idle so red light is out. It should read about 7.4v at the battery. Turn the headlights on and measure again at same engine speed to see if that 7.4v is still there.

After that measurement, it gets more complicated. The max current for 52's should be set at approx 35 - 40 amps (Packard max spec is 40 but some are set less) so a heavy duty ammeter is required -- most regular meters are limited to 10A so won't work. Some expertise is also needed because you have to jumper out various things while measuring to get correct readings. Since problem seems load dependent I would suspect the generator or regulator is not putting out the full current. Lights have a CB limiting them to 20 amps but run less. Unless radio, heater, lights & something else heavy is on at the same time, draw should never reach max.

It could be an adjustment but if the gen and regulator are old and untouched it could be time for a rebuild. I would suggest taking it to an electrical shop and have them check it.

thank you for the insight ,Ill try the voltmeter in the am ,this is tricky buisness!
I had some superstitious ideas;
I recanttly replaced the battery with a larger capacity one ,its new ,I was wondering if it hadnt been completely initially charged if it might pull current ?I had trickle charged it for an hour before the install..
I had thought that when the battery cables are undone for any reason, when replacing them one had to repolarize the voltage regulator by touching the inner two poles with a loop of wire for just a second, one sparks worth ...,have I damaged it?
I was wondering if modern freeway speeds cause the generator to spin too fast ,My speedo needle wobbles so im never really sure but I usually never go over 65 in the old 200 .on my am commute, Ill run the lights and heater this is when I saw the battery light faintly on .
The generator has been rebuilt who know how many times maby someone put the wrong size pully on it at one point so its over spun
I recantly replaced the spark plug wires /coil wire with modern ones,ACCEL . They have this funny fiber inside .They semed to have worked great ,I got improved engine performance after the swap ,I wonder if they are causing a problem .
I put dielectric grease on the center shaft of the distributer, filled the side grease cup with regular grease, and oiled up the felt ,made a short?
almost all of the electrical components have been replaced in the old car ,the regulator /battery /generator/engine harness /starter /cables /so i dont think its a question of something worn out ,perhaps not rebuilt right or out of adjustment ,the lights have a "CB" whats a CB ?
the battery light came on when the last generator went out maby this rebuild is failing maby time for a bench test

G'day all, I had this problem on a Packard in the Sixties and it was caused by using a Negative ground Voltage regulator on a Positive ground Packard. I would check it out and confirm that you have a Positive ground Voltage Regulator. Unless the car has been changed to Negative ground and then it's the other way. Peter Toet

Quote:
"battery light on the dash glows very faintly if at highway speed with the lights on ,I can see it at night ..."

At nite, hiway spped, lites on, FAINT glow. Turn OFF headlites which means dash lites go off. If faint glow ceases then there is a problem of lite from OTHER dash lites bleeding into the generator lite display of the dash. This is not uncommon in any dash display of old age.

wow that last entry will take some courage ,turning off the lights at 60 at night and staring at the dash but ill try!this may be goodbye but
I dont think thats it because the battery light isnt on at night unless Im driving fast ,>60 ,it doesnt happen with all the accesories on( heater fan ,lights ) at a slower speed

I tried stacking the accesories today ,at 60 ,first the lights ,no glow , then plus the blinkers ,no glow ,then the rodio,faint glow ,then the heater fan ,more glow ,by far the heater fan was the biggest effect maby it has an excessive draw bad motor? maby the fan motors grounded out backwards,the coil was backward Ilearned to check this on the packard site and voila !
,someone mentioned a voltage regulator wired backward how would I tell ?,mine seems to be grounded to the base of the voltage regulator assembally itself where it bolts to the firewall .
the generator has a black wire thats attached to its case Im guessing its a ground .
the positive ground from the battery goes to the block I wonder if the body isnt grounded to the engine ?maby I should run a ground from the body to the engine somehow ,
wow complicated!

perhaps the generator is going out such that at higher rpms the field coils are disrupted or the brushes overwhelmed

has anyone heard of the 6 volt alternators ,powergen's they are called .they cost about 400.00 .the voltage regulator is internal .they look just like a generator ,That should fix the higher rpm output problem

by nature of its construction the alternator can handle higher rpms and still work because the current is generated from the outer stationary part not the spinning armature,so theres no jump across over taxed brushes (check the "stovebolt tech tips" "6 volt charging systems" by jerry herbison ,nice illustrated walkthrough of the 6 volt d/c charging system system)

ps; is there a way to know if my blower fan motor is drawing too much or grounded backward?

Grounding either wire doesn't matter on that motor unless there is a short. Factory used a 20 amp fuse and that should blow if there is excessive current.

Again you have the problem of ordinary meters not having enough capacity in trying to check current. Look at your meter and see what the max amp rating is. If 10amp, probably need something else as the meter fuse may blow but if 20 MAYBE you could measure by configuring for amp measurement & putting meter in series with one of the leads.

You could get an ordinary inexpensive universal aftermarket ammeter at the parts store that will read higher. You can use that to test the motor (although the graduations are coarse so mostly guesstimates) or it could be added in series in the circuit just like cars with ordinary instrument panel ammeters and give you an idea what the generator is doing. Several have added one in the engine compartment just to keep an eye on things. In your case you'd probably want it inside--at least till the problem is found. Here are some of those available at Amazon.

I don't know anyone using the powergen personally but don't recall hearing any negative. Downside is cost and if it fails in the middle of nowhere might be hard to get replacement or find someone to work on it.

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tHANK YOU iLL ORDER ONE ,Perhaps I an find an unobtrusive spot in the cabin to mount it .Ill need a wire to light it and one to feed it current ,any suggestions where to splice in ?
I tried the voltmeter test across the poles of the battery ,it read 6.3 v. when I revved the engine ,no change ,I tried adding on some accesories ,;lights blower fan while at idle ; the voltage dropped across the poles down to 6.18 ,and revving the engine didnt change it upward ,I had thought the voltage would go up to 7.5 if charging ,does that mean Ive a noncharging generator again ? should I have the voltmeter on the generator ?
the generator has been replaced and rebuilt several times on the car!

Dear Steve:

7.2-7.4 volts is the spec.

Did you ever make a new charging system harness for your car?

To test your system, use a jumper wire and jump the generator field to ground at 1500 rpm. If the voltage goes way up your harness is poor or your regulator requires adjustment. If the voltage doesn't change the generator is burning out.

Hope this helps.