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Hi guys, looking for help. I have a 74 C3 and trying to figure out how the charging system works. It seems this car is supposed to have the voltage regulator built into the alternator, however it looks like this car also has an external regulator mounted to the firewall. Any thoughts?
Thoughts? Well, yes that certainly does look like a voltage regulator. Or it could be a regulator cover being used to cover something else?
Pretty strange someone would go backwards and install a earlier alternator and external regulator. But who knows what a previous owner was thinking. Perhaps they had parts laying around, so rather than purchase replacement parts they used what they had?
Bottom line, follow those wires.
Hard to actually follow the wires on the back of that alternator. But WOW that looks terrible. Looks like 2 to many wires going to the rear of that alternator as well.
I really don't know what you have going on there.
2025 C3 ('68-'73) of the Year Finalist - Unmodified
2024 C3 of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
Originally Posted by 4-vettes
Hard to actually follow the wires on the back of that alternator. But WOW that looks terrible. Looks like 2 to many wires going to the rear of that alternator as well. I really don't know what you have going on there.
RogerRaines
Well, that was really curious.
I cannot imagine why anybody would go backwards like that?
My 68 came with a 63 amp externally regulated alternator and it could barely keep a positive charge at night with just the lights going.
2025 C3 ('68-'73) of the Year Finalist - Unmodified
2024 C3 of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
Originally Posted by carriljc
RogerRaines
Well, that was really curious.
I cannot imagine why anybody would go backwards like that? My 68 came with a 63 amp externally regulated alternator and it could barely keep a positive charge at night with just the lights going.
Shouldn't be. Must have been another issue, bad ground, poor wiring, or a loose connection. My 68 came with only a 37 amp externally regulated alternator and everything works just fine as it should.
Certainly was. I replaced the regulator and even ended up replacing that POS alternator ..... then I converted a 94-amp 12si, then went to a CS-144, and now a DR44G......
the 94-amp 12si was wonderful for my stock loads.... then I started adding other crap.... so kept upgrading.
Originally Posted by 427SIXPACK
Shouldn't be. Must have been another issue, bad ground, poor wiring, or a loose connection. My 68 came with only a 37 amp externally regulated alternator and everything works just fine as it should.
74 C3 voltage regulator
