Alright I've basically looked through this forum and all my books I have been trying to find an explanation but have yet to so I decided to post about it..I converted to an alternator a while back and everything seemed to be going dandy. The only thing I ever noticed was that the Gen/Alt light didn't go off right when you started the engine but only after you reved it up to about 1100 rpms or if you choked the engine it would start with a high enough rpms I suppose to start correctly. Well I have been trying to figure out why my battery will slowly discharge. I removed my stereo wire from the battery so it only gets power when the ignition is on and now the only thing physically hooked to the battery besides my cables is the insta head system I have.

I checked the battery after I got done charging it with a trickle charger and its putting out 12.12v.. I checked the green wire and I found it odd that its only supplying 11.58v which I've read I has to supply 12v. I did this by turning the ignition to where the lights come on and having a voltage checker plugged into it..  The alt itself will put out 13.89V and the battery receives this.. So what can be wrong? I know the alt is supposed to put out 14.5v but if its putting out above 12v it should technically be charging right?

I have petronix ignition setup with a normal VW starter... All test were ran with engine ONLY and no other "extras" although I did run the engine with everything on and the volts to the batter were still above 12.5v.. Any suggestions would be greatly appreciated..

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I found something you might check, seems the positive wire can fray and make a grounding contact....  Maybe you have this problem or could be grounding inside where the Pertronix mounts....  I don't know about VW's if it requires a resistor or not ....maybe someone may know.
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When You changed over to an alternator, did you didconnect the old voltage regulator??
as it isn't needed and will cause problems...
it should be disconnected...
Does Your alternator have two wires coming off it??
if so, the small terminal should go directly to the alternator lamp in the speedo...
You can disconnect that small wire and connect a small bulb to that terminal and ground and it should come on with the key turned on.. and go off once the engine starts,,,
sometimes if My engine is idling too low I need to rev it slightly to get the light to go off...
or 3 wires...
if 3 wires you need an alternator regulator...
the red alternator lamp excites the alternator into charging
so it shouldn't be On until 1100rpm
I could say more...
but its a bit involved and you would need extra wires etc...

68AutoBug - helping keep air cooled Volkswagens alive in Australia & around the World -
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It could be your starter. if your starter solenoid is going bad it can draw power all the time.  Take a test light, disconnect the pos+ battery cable and touch one end to the pos+ post of the battery the other end to cable end. If it lights up you have a short somewhere. There are other components of the beetle that's always has power and could short.

saving as many as I can
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On the points and stuff the wires aren't worn or anything but I doubt it would be my problem since that sounds like it wouldn't work at all if the plastic was worn down like that. On removing the regulator i did but I actually left it in the car but just followed the diagram I received with the kit on how to hook it all together.. I'm glad I'm not the only one on the revving the engine to get the light to go off.. So I guess that's not my problem either.. Anyone know how long you have to run the engine to restore health back to the battery after it was hit with a "start" from the starter? Maybe its my short driving spurts I do..
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How old is your battery? They should take more than one hit from the starter without needing to run for a while to charge.One other question did you perchance pull the positive lead off the battery when the engine was running. If you did then the alternator has a burned diode and will need to be serviced. This will cause low output and a slow voltage drain also.
66 Ghia, "Dexter" 76 flat window Beetle
It's not a Car it's a VolksWagon!
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Battery is fairly new and I never removed the battery cables while it running..
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take one of the battery leads off and put a light bulb between the battery post and the battery terminal...
if the bulb lights up..
You have a problem with leakage...
the next thing to do...
with the bulb or lamp still connected...
take out one fuse at a time...
when the lamp goes out...
whatever is connected to that fuse is the problem...
I would take the the old voltage regulator that was used with the generator out of the car...
any voltage over 12 volts should charge the battery..
the higher the better... 13.8 to 14.5v
An alternator should keep your battery charged all the time...  does Your engine start as soon as you turn the key
or do You have to turn it over a few times??
are the battery terminals nice and clean.. and tight.??
a loose terminal can start your engine but NOT take the charge from the alternator..
or only take a bit of a charge intermittently.
I found this out recently, when I went to jump start a V8 car... there was NOT enough current getting thru My battery terminals to start the other car...
I tightened the battery terminals and haven't had any problems since...

68AutoBug - helping keep air cooled Volkswagens alive in Australia & around the World -
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Well what I ended up doing for now is just disconnecting everything to the battery.. I moved the radio to the ignition switch so it gets its power when its on only.. no clock or anything..
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