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Electrical problem

Charging issue in my old FrankenFord. My truck is an early 70's box turned into a dump truck. Base is an f350 and cab is 1970 f100. I've found two related wiring schematics, this is the one that matches my wiring... http://www.fordification.com/tech/wiring/wiring-diagram-70F350_master.jpg (sorry for the outside link...) Nothing has been changed the 8+ years I've owned the truck except for the random replacement of the fuse link. The last several months I have been trying to sort this problem as it seems to have gotten worse. I installed blade fuse holder and even replaced entire fuse box with blade fuses. No change to problem. All grounding seems ok. Replaced voltage regulator, same. Tried a spare alternator, same, both bench tested good. One thing I have discovered is charge voltage is 22-24 volts, which I assume answers the blown fuse. I can't say I understand how system works but lack of stater connection confuses me.:hammer:
 
Charging issue in my old FrankenFord. My truck is an early 70's box turned into a dump truck. Base is an f350 and cab is 1970 f100. I've found two related wiring schematics, this is the one that matches my wiring... http://www.fordification.com/tech/wiring/wiring-diagram-70F350_master.jpg (sorry for the outside link...) Nothing has been changed the 8+ years I've owned the truck except for the random replacement of the fuse link. The last several months I have been trying to sort this problem as it seems to have gotten worse. I installed blade fuse holder and even replaced entire fuse box with blade fuses. No change to problem. All grounding seems ok. Replaced voltage regulator, same. Tried a spare alternator, same, both bench tested good. One thing I have discovered is charge voltage is 22-24 volts, which I assume answers the blown fuse. I can't say I understand how system works but lack of stater connection confuses me.:hammer:

My lands.....
A 70 model doesn't take that much juice ,its got to be a ground somewhere,
maybe a body ground to chassy or a naked wire short ,like to any lights!:)
 
is the voltage regulator well grounded? maybe check to make sure the wiring is good from the regulator to alternator? wires have less hen 5ohm resistance

was a new solid state regulator installed or an older spring type?

maybe were the source voltage for the regulator is lower only in that area causing higher outputs though out the rest of the system. voltage regulator still getting feed from starter relay ( i think that were it should get its feed, but im not sure)
just ranting out ideas
 
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In the process of trying to eliminate possible bad wire... removed all radio wiring, cut feed to roof lights, pulled all fuses... V regulator has ground wire cleanly bolted to it, will sand a rust free spot under its mount bolts. I believe I have wires narrowed down to a select few. When I unplug the wire going to stater terminal on VR, Truck starts without blowing fuse, but of course, doesn't charge. That wire runs to dash and branches off several places on way to ignition. I suspect a naked wire short, which is why I've removed all the shade tree radio wiring.The dash harness looks to be fully wrapped and intact. How can I best test wiring in harness under dash without pulling it all apart? Oh yeah, I replaced the ignition switch too. All the parts were replaced last summer and it seemed to work ok for a while. Thing usually sits most of the winter.
 

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