MAD ELECTRICAL?

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I just tested the alternator on the car with my multimeter set to volts it was bouncing between 15 and 16 volts all the time. Any thoughts? I am going to add to this, both the mechanical and solid state regulators are trying to hold it to 13 to 14 volts, I think this might be where all the pulsating is coming from. I am going to pull the alternator and have it checked at a parts store. Is there anything I should make sure they check? Thanks for putting up with me.
 
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Sounds like it is not regulating. I don’t understand what you mean about the regulators and holding the voltages. All alternators have built in regulation nowadays, but back in the day I never replaced an alternator without changing the regulator too. You might also check the field connections from the alternator to the regulator & make sure that is good.
 
Mike69cuda said:
Sounds like it is not regulating. I don’t understand what you mean about the regulators and holding the voltages. All alternators have built in regulation nowadays, but back in the day I never replaced an alternator without changing the regulator too. You might also check the field connections from the alternator to the regulator & make sure that is good.
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What I am saying is the alternator might be putting out too much, bouncing between 15 and 16 volts, the regulator is mounted on the firewall, engine compartment bulkhead. My volt meter in car is running at 13 to 14 volts bouncing around, I think the regulator is trying to keep the voltage correct. There is no internal regulator in the alternator that I know of for 1966 cars. Thanks for reply!!
 
Yeah, didn’t mean to imply that there was an internal regulator, just that it is a lot simpler in modern times. The regulator should be controlling the output of the alternator. Don’t really understand why there is so much difference between the two meters, unless one of them is inaccurate.
 
Thanks, the car has no ballast resistor because of after market ignition that was in the car when I purchased it. Can this be the problem? Thanks
 
Some coils don’t use ballast resistors. Don’t think that could be an issue is the car is running good. Can u post a pic of regulator and wiring on back of alt? Does the voltage smooth out at high rpm? If so what does it settle at?

You might try measuring the voltage with your hand voltmeter as close to where the car voltmeter hooks up to see if they read the same.
 
The reason I bought the resistor up was that in the wiring diagram it shows wire R5 from ignition side of regulator to resistor, and J2 and J3 from resistor to ignition switch. The ignition system doesn't need the resistor. There are only two wires on back of alternator, battery and field. Thanks for your input.. I think I am going to ask the resistor question in the early "A" body forum..
 
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I have a question along the bypass MAD style. I removed my dash cluster tonight and had 3 words to the ammeter gauge? 1 red 3 black. 3 blacks were on common terminal. I haven't looked deep enough through it yet but I dont fand mention of 4 wires anywhere
 
My 69 had only one wire on each. I am not familiar with other years. I think the red is the feed from the battery and the Black is to the loads (ignition, radio, heater, etc). I don’t know if those are factory or not. Do they look like part of the factory harness?

There is nothing wrong with more wires there if they are fused somewhere in the circuit.
 
Mike69cuda said:
My 69 had only one wire on each. I am not familiar with other years. I think the red is the feed from the battery and the Black is to the loads (ignition, radio, heater, etc). I don’t know if those are factory or not. Do they look like part of the factory harness?

There is nothing wrong with more wires there if they are fused somewhere in the circuit.
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Appreciate the response. I've attached a picture of 1 wire end. Looks like a circuit breaker to me? All are original wires and run into stock harnesses. I plan to complete the mad electrical change and just have all these wires that were to the amp gauge tied together, just like they were.

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Yep, looks like a circuit breaker. Since those are all hot (+) wires, make sure everything is well insulated and tied down so it can’t rub on any ground. Never hurts to replace 40-50 year old circuit breakers to make sure you are protected while you are in this far.
 
Thanks a ton. So as I'm going through the changes I was planning I run into a goofy situation that I cant seem to comprehend. It doesn't match with any diagrams. Brown wire from alternator runs through firewall (grommet style not bulkhead) runs to ammeter then run back from ammeter through firewall (grommet) to starter solenoid. I attached a picture. Theres no fuse or fusible link between the starter solenoid and the positive running from the ammeter or even the alternator to the ammeter. I assume this is a previous owners fix and all I need to do is add a fusible link between the grommet shown and the starter solenoid? I already disconnected the ammeter gauge.

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My experience is limited to 60’s a bodies, so there may be others on the forum that can speak to this better. In general, however, I don’t see an issue with what you describe except for the lack of a fusible link. The feed wire from the starter relay (battery supply) should go through a fusible link, then to the plus side of the ampmeter. All the loads and the alternator come off the black side of the ampmeter. This way it measures all the current going in or out of the battery.

The white connector in the picture looks like a fusible link connector. Is that what it is?

The closer the fusible link is to the battery, the more protection you have.
 
I was thinking that the white connector looked an awful lot like the fusible link one. Can you post a picture of more of 5be wiring? I read somewhere on the forum that the firewall grommet you have was installed on fleet cars, so it may be factory
 
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