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Over charging/no charge batter 68 roadrunner

bigbother14

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Winthrop harbor Illinois
Hello everyone I have an issue with my charging system on my 68rr I’ve changed the alternator/battery/voltage regulator the only way it will charge and will also over charge its i add a jumper wire from fld wire green to ign wire blue added here in the photo it’s the red wire on top picture for attention when I take out the jumper wire it stops charging and the voltage regulator was also replaced not sure what to do next

IMG_4826.jpeg
 
I've been having problems with getting a good alternator to "match" the VR.
By putting the jumper there, you are making connection by bypassing internals of VR.
It could be that VR is not adjusted correctly and internal solenoid cannot do the job of directing voltage to ground to avoid overcharge.
Is old VR still good? Have you tried using it?
 
I've been having problems with getting a good alternator to "match" the VR.
By putting the jumper there, you are making connection by bypassing internals of VR.
It could be that VR is not adjusted correctly and internal solenoid cannot do the job of directing voltage to ground to avoid overcharge.
Is old VR still good? Have you tried using it?
I changed it because I was having the same issue the old one needed do be Jumped to get the battery to charge once the jumper wire is disconnected it’s stopped charging so I figured the VR was my issue but the problem continues even after replacing alternator and also battery
 
You likely have a bad new regulator.
Also check that you have a secondary ground from the back of the head to the firewall and that the mounting screws make good contact with the regulator metal.
 
You likely have a bad new regulator.
Also check that you have a secondary ground from the back of the head to the firewall and that the mounting screws make good contact with the regulator metal

You likely have a bad new regulator.
Also check that you have a secondary ground from the back of the head to the firewall and that the mounting screws make good contact with the regulator metal.
Ok il check for a good ground connection I do remember screwing down tightly just to add my alternator only has one fld wire not two from the pic posted it’s only the green the other small wire is grounded to the body of the alternator not sure if that matters
 
Stupid question. Your wiring diagram is for an isolated field( 2 field wires) alternator yet your vehicle should have a grounded field( one field wire) alternator. Has it been changed to a late(square back) alternator and electronic VR?
 
Stupid question. Your wiring diagram is for an isolated field( 2 field wires) alternator yet your vehicle should have a grounded field( one field wire) alternator. Has it been changed to a late(square back) alternator and electronic VR?
Yes the diagram later style I have the old mechanical VR the alternator was changed but still the same one field wire and one is grounded to the body of the alternator and the return wire to the battery that’s about it I used that diagram to show what i had to do to get it to charge but it’s overcharging if left that way
 
I had the same issue on my 62, and the third VR, was the answer.
 
I like the squareback dual field alternator with the solid state regulator.
They work great and never have these issues.
 
Hehe that’s a diagram I edited looong time ago with colors on wires and saying where to splice the reg conector pigtail when making the conversion from mech reg/single field alt setup to a elect reg/dual field alt setup
 
I had a similar issue on my '64, no charge and then jump the wires and over charged. It ended up being the bulkhead connector. I bypassed the bulkhead and went directly to the ammeter with fusible links, problem solved!
 
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