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charging problems

brad 66

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new alternator ,new voltage regulator ,new battery still only getting 12.36 volts any suggestions
 
Regulator has a good ground? If you run the idle up a bit to 1100 rpm what happens to the voltage?
 
the ground is in the bolt that holds it on right ? when i it rev it up it might go up .02 volts
 
full field the alternator.... pull the field wire off at the alternator, put a clip lead from the output stud on the alternator to the field terminal on the alternator. You should hear the alternator load up . voltage should start to climb. Be careful not to ref the RPM too much, watch voltage not over 15 or damage.... if this works then you need to run a few test possible broken wire or loose wire in charging system...
 
Should be two bolts holding the voltage regulator to the firewall. Yes, would provide ground, but on repaints the pant can cause a ground problem.

If you remove the field wire from the alternator and attach a jumper wire to the field terminal - touch the wire to a good ground momentarily while monitoring the voltage. Should have 15 volts at least.
 
Are you checking the battery voltage when the car is running? If not, that's your problem.
 
yes check with car running .when i pull field wire then jump across to the stud is that to test alternator ?
 
Yes. Puts the alt at full output. The test is slightly different between single field and dual field alternators. I figured you had a single field alt.
 
waiting for rain to stop then i will try .if the alternator works .then i will start checking wires first by running field on alternator to field on regulator?
 
i am getting 15 volts at alternator ran a new field wire still not charging
 
If your wiring is original, full alternator output goes through the bulkhead connector to the amp gauge, back out through the bulkhead connectors to the starter relay, ending up at the battery. The charging voltage from the alternator has to follow that entire route in order to charge properly. The spade connectors in the bulkhead connectors were a Chrysler flaw -- too small for the amperage. They often burn out or generate a lot of resistance. If the connections at the amp gauge get loose, they get hot and generate a lot of resistance.
 
the next step is the wire from regulator to bulk head connector but not sure how to get the wire out of connector
 
can i run a lead from the regulator bypass the bulkhead to the -battery to test the alternator and regulator
 
This is a simple diagram for your alternator output charging circuit.
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Some people add an 8 or 10 gage wire directly from alternator output to the starter relay (as shown in this diagram). If you do this you can leave all other wires connected --- but, the new wire must include the fusible link. This reduces amperage going through the bulkhead connector and basically turns your amp gauge into a volt gauge. But, this allows full alternator current to go straight to the starter relay which goes straight to the battery.
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And most importantly buy a fire extinguisher to have in the car. 2nd clean every ground in the car. That probably wont fix this problem but will improve any old wiring system. If you’re loosing that much voltage in the wiring it’s turning into heat somewhere. Unless you’re lucky there is more than just the charging wire melting. Check each wire in the charging system for voltage drops to find the one that is the problem. Get a service manual or schematic to help. If you’re not at least familiar with electrical, start looking for a shop that has experience with classic car wiring.
 
With the indicated items you have replaced, the only thing remaining is the wiring. Other comments here are good suggestions to narrow down the problems. If you inspect your related wires and see any greenish corrosion looking into the housing where a wire enters a connector or where a wire is crimped on a lug, that's a potential problem. With only a nominal 12 volt system, even a slight amount of resistance in any of the wiring from poor or corroded connections will be problematic.
Concerning grounds, if you wiring is as it would be if original, you should have a good solid heavy wire connection from battery neg. to front drivers side of the engine block. On passenger side rear of the engine block, you should have another heavy wire that provides a good solid ground from the engine block to the firewall. All with good crimps, no corrosion and tight mechanical connections.
For the Voltage regulator, I would suggest making a short ground wire with proper sized lugs to tie the regulators case to that firewall ground, or assure that there is a good solid clean ground connection to the bulkhead from the case of the regulator.
As a previous posts indicated, the heavy + 12 volt wiring that goes thru the bulkhead connector MUST have good solid electrical connections, no corrosion and good crimps. Same for the inside of the bulkhead connector under dash. The wiring to / from the alt gauge is critical. Good solid crimps and assurance that the mechanical connections to the studs of the Alt gauge MUST be solid and tight. It does not take much resistance in the main 12 V electrical path to cause heating at the connections. Once the heating starts, and just continue to get worse with time till you have a meltdown or worse a fire. The fire extinguisher is a great idea in a car as old as this. I would sugest a Halon or CO 2 type, not a dry chemical type. Good luck with your issues..
 
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