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Discussion Starter #1
Swapped alternators on CS130 I ran S to battery lug on back of alternator and L wire to the F and #4 at voltage regulator car will start with F and #4 disconnected but no charging, if I start car and then put the F and #4 wire together it charges but won’t start. Any help would be greatly appreciated.
 

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Swapped alternators on CS130 I ran S to battery lug on back of alternator and L wire to the F and #4 at voltage regulator car will start with F and #4 disconnected but no charging, if I start car and then put the F and #4 wire together it charges but won’t start. Any help would be greatly appreciated.
https://www.hemmings.com/blog/article/delco-cs130-alternators/

Pay special attention to the last four paragraphs
 

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Quote from the Hemmings article:
"it is necessary to install a 50 ohm diode in the wire leading to the “L” terminal."
I've been working in the field of electronics since 1965 and have never heard of a diode specified by resistance. A diode has a fixed voltage drop of roughly 0.7 volts, a maximum current and a peak inverse voltage.

" if I start car and then put the F and #4 wire together it charges but won’t start."
Can you amplify this statement? Is the car started but won't start?
 

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Discussion Starter #5
Yes if I have F and #4 not connected car will start then I connect them while running and it will charge then will not start back up also would gen light serve as resistance
 

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Discussion Starter #7
Yes it won’t start unless I disconnect the F and #4 at voltage regulator
 

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You shouldn't have any wires going to the old regulator, as it should be removed altogether. Just connect the blue and brown wires together at the connector and leave it unplugged.
 

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Discussion Starter #9
That’s how I have it brown and blue connected and plug out of regulator and I’m using red wire from bat terminal on alternator to horn relay
 

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Discussion Starter #11
Turn over but no ignition I have msd pro billit distributor and msd 6al and msd blaster 2 coil
 

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On the schematic #13 there is a small red wire that is the on/off signal to the MSD-6. Where does this wire come from on your car? This is basically how your ignition is turned on and off. There is not much current draw, so most any voltage will keep the ignition going.

My thinking is that somehow there is a cross-connection between the brown lamp wire on your regulator connector and the control power to your MSD.
If the engine isn't running, the brown wire is grounded through the field. If you disconnect the brown wire this allows it to float up to 12v through the generator lamp/resistor and possibly providing the power to activate your MSD.

If I was troubleshooting this problem, I would disconnect the large wire that goes from the solenoid to the starter motor to keep the engine from turning over while I recreate all other aspects of that cycle. I would put a voltmeter on the small red wire going to the MSD, and read the voltage while I tried to start the engine, both with the alternator connected and without.
 

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Discussion Starter #18
I just bypassed factory harness and ran a new wire from accessory to a indicator light then to L terminal on alternator and put S on bat+ post on alternator. Then ran 4 gauge wire from alternator positive and ground to battery now have 14.3v at 800 rpms.
 

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You really don't need a 4 gauge to the battery from the alternator. The most current that should go that way is about 30 amps when it's heavily discharged. The original wire is quite sufficient for this as it's 10 gauge with a 14 gauge fusible link
The 4 gauge wire should go to your power distribution block, like the horn relay or other dedicated terminal. Running big wire from the alternator directly to the battery may result in a fire if you have a short.
Your alternator ground should be connected to the block, because when the alternator is running all current returns to the case of the alternator. Just bolting the alternator metal-to-metal to the block is good enough
The battery just starts the motor. When the engine is running, it's just a load on the alternator. If the motor turns over well on the starter, it's good.
 

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Discussion Starter #20
I did run a ground from alternator to block I hate to take out all of 4 gauge wire do you think I could put a fuse inline on battery to alternator to protect from short and what size fuse would you recommend. Thanks
 
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