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03-08-13, 11:52 PM
(This post was last modified: 03-09-13, 01:37 AM by 383bee.)
Looks like I get to add my elec probs to the list.i bypassed ammeter on my 69 bee.new wiring harness,updated regulator dual field alternator,battery is about 2 weeks old.put a voltmeter on it today and now it's overcharging.have ground pigtails on reg.mp box block,the whole works.voltmeter comes up 16-17 volts at about 2000 rpms.i get 18 volts at alt stud and over 16 at battery.do I start with a another new regulator?maybe alt is bad?thanks for opinions,David. Btw electric sucks!
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The regulator controls the field based on what it senses battery voltage be. A high resistance connection between the regulator and the battery or a bad ground will cause the regulator to falsely believe that the battery is dead so it will end up overcharging the battery.
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Sedanman - thanks for the reply.i checked my grounds with ohm meter and everything checks out there as far as i can see.everything i can check points me to voltage regulator - new but its a cheap chinese model.any way to check one or best to try a new one?i started out thinking alt was the problem with overcharging but i think maybe wiring or vr.thanks again,david
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You need to check the voltage at the regulator. The best way is to do a voltage drop test. You should no volts going between the input of the VR and the batt+. Any voltage means resistance in that circuit. If no volts, then get annother reg.
President, New England chapter of Coronetaholics anonomous.
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thank you.that looks like where i need to go.i have had more problems with this elec stuff.some of my probs have just been reman and cheap parts.i am on my 3 rd autozone alt and 2 nd battery in a yr.this vr is prob toast,but we'll see.thanks for help.
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Hot Rod has a decent article this month on Mopar electrical gremlins..
I love Mopars so much I'm date coding the skid marks in my underwear.
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Ohm meters are the cause of male pattern baldness! The best way to find resistance on a automotive circuit is voltage drop. Measure voltage frompoint to point in a circuit with the circuit under load say from the battery positive to the regulator sense terminal. You SHOULD get a reading near zero. If you get a reading of a volt or two then you have a problem, that's the voltage that was used up overcoming the resistance in the wire or the connections. Am ohm meter might tell you that the wire was fine bu\ecasue the ohm meter can only load the wire with a few milliamps. A resistor (or a crappy connection) is a conductor until it's out under load.
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thank you for the tips.i will start using this method to look for reasons why i am seeing the over charging.i just did'nt know that an alternator could put out that much voltage like it has.i have a lot to learn about this elec stuff!
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What kind of Alt are you running? As well what kind of Voltage reg are you using?
I upgraded to the 70`s / 80`s Flat pack triangle connector Voltage regulator. I have the squareback dual field alt and went thru a overcharge issue while testing my workmanship during the upgrade.
It was due to voltage drop thru bulkhead and a bad ground at the Voltage regulator.
Fix the ground and put the Vr on a relay...
Read Hot Rod Mag 05/13 issue
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I am using a 65 amp dual field square back alt and the 70s regulator too.new wiring harness,vr,battery.I have bypased the ammeter and drilled out the bulkhead for the 2 large power connections.have charging wire coming off the alt with the correct fusible links as well and still have overcharging.i am sure it's some kind of voltage drop somewhere.just gotta find it.
