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electrical issues, dimming lights, occasional stalling, rough idle at stop

Evan, you might want to check your local NAPA store's return policy on electrical items if you decide to buy a new or rebuilt alternator. Most parts stores won't take back alternators that have been installed as a 'test'.
 
He did check all the diodes and tested the continuity of some other parts when he had it on the bench. I saw on his bench top multimeter that each of the diodes had exactly the same reading. He did a bench test before and after changing the brushes. Trying to stay hopeful. I also asked him how many amps my unit was putting out and he said 65 amps.

I'm halfway through the bulkhead "upgrade" and will update once I fire her up.
FYI....
Each diode should have two(2) different readings...in the forward or conducting direction, the diode's forward resistance should be approximately 10 ohms (+/-) and in the reverse direction or blocking direction, the resistance of each diode should measure infinity or NO resistance. Each leg of the stator windings should read approximately 0.1 ohm (+/-) each, measured to the common connection point and infinity measured to ground. The rotor should also measure approximately 0.5 ohm (+/-) to each slip rings and infinity measured to ground. Were the brushes fitted to insure even contact with their respective slip ring? If everything regarding the alternator checks out, you should continue to explore the bulk head connections for corrosion and loose connections.
BOB RENTON
 
Completely redid the bulkhead by drilling out and putting some 12 gauge stranded wire through it. I then soldered all those wires to the wires for the under dash harness. Then added brand new insulated spade connectors on engine bay for all 14 connections on bulkhead. Fired it up, and same thing as before.... horrible sporadic ammeter readings, jumping all over. Will immediately die when put into DRIVE and will even sometimes die in NUETRAL now (always ran fine in neutral before). Then a minute later the problem is actually fixed for a minute or two. Then now it goes back to not working. Very weird.

Also after the car dies... when the engine is not running and the ignition is still switched on, I noticed that the ammeter will tick toward the D side. It will make an audible "click" sound when it does this. I don't think this happened before.


Almost positive my alternator or VR is bad. That guy, even though he didnt charge me anything and I could tell was trying to help me made the problem worse I think.

I switched back to my original VR since the brand new replacement was letting out 17+ volts. Maybe the original is bad also ( but in another way ?) And maybe that has something to do with all this...

They did a charging test at autozone and the guy said the test told him my VR was bad... that's what made me get the defective replacement anyway
 
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Evan, you might want to check your local NAPA store's return policy on electrical items if you decide to buy a new or rebuilt alternator. Most parts stores won't take back alternators that have been installed as a 'test'.
The rebuilt alternator says it has a lifetime warranty if I'm reading that correctly. Also Napa basically let's you return anything within 30 days.
 
Do the wipers work?
I had a bad wiper motor on my 66 (dead short), it tripped the breaker in the drivers kick panel.
It would click on/off periodically similar to what you describe.
I don't know if a 64 is similar. Just an idea.
Perhaps scale back what is getting powered, start with just the ignition and see what happens.
Then add circuits one at a time, sounds like something is wreaking havoc.
This would include the voltage regulator, with a good charged battery just disconnect and insulate one side - see if the problem goes away.
 
Now it's not even starting. Just a labored cranking over. Maybe its charging ability diminished enough to wear down my battery
 
Do the wipers work?
I had a bad wiper motor on my 66 (dead short), it tripped the breaker in the drivers kick panel.
It would click on/off periodically similar to what you describe.
I don't know if a 64 is similar. Just an idea.
Perhaps scale back what is getting powered, start with just the ignition and see what happens.
Then add circuits one at a time, sounds like something is wreaking havoc.
This would include the voltage regulator, with a good charged battery just disconnect and insulate one side - see if the problem goes away.
The wipers work sometimes, sometiems they dont, sometimes they just twitch at the bottom of the windshield
 
Now it's not even starting. Just a labored cranking over. Maybe its charging ability diminished enough to wear down my battery
Actually I dont know what's going but it still won't start. I took out my new multimeter and noticed that the battery is losing voltage when I crank the ignition over and even when I just turn ignition on.

I have my multimeter hooked to battery and got these measurements.qqq

Battery currently reads 12.4 volts when sitting, nothing turned on.

With ignition switch on it goes down to 12 volts

When I start cranking it drops down to 10 volts

What could this mean?
I cant even start the car now to do voltage drop tests.
 
12.4 is a little low, 12.7 - 12.8 would be the target.
I suggest unplug the wiper motor and charge the battery.
Yes it's going to drop when cranking.
 
I'm gonna put the battery on the charger.

So dropping down to 10 volts while cranking is normal?

I also happen to have a brand new ignition switch and starter relay that I never got around to installing I was thinking of throwing them on and seeing if that does something. especially since power for the whole car basically goes through that relay (I think)
 
I'm gonna put the battery on the charger.

So dropping down to 10 volts while cranking is normal?

I also happen to have a brand new ignition switch and starter relay that I never got around to installing I was thinking of throwing them on and seeing if that does something. especially since power for the whole car basically goes through that relay (I think)

Usually, with a good battery, the terminal voltage will drop to ~ 10.5 volts (+/-) during cranking or if the battery is being tested under load. Less than 10.5 volts is a indication of a partial sulfated cell and you should consider replacing it. But try a slow over nite charge at ~5 amps max. to see if the battery can accept and hold a charge. If the battery has removable caps, add distilled water to cover the plates. BTW....what type of voltage regulator are you using? If the new style, insure the regulator's is securely grounded.
BOB RENTON
 
Usually, with a good battery, the terminal voltage will drop to ~ 10.5 volts (+/-) during cranking or if the battery is being tested under load. Less than 10.5 volts is a indication of a partial sulfated cell and you should consider replacing it. But try a slow over nite charge at ~5 amps max. to see if the battery can accept and hold a charge. If the battery has removable caps, add distilled water to cover the plates. BTW....what type of voltage regulator are you using? If the new style, insure the regulator's is securely grounded.
BOB RENTON
ok its on a trickle charger now. the battery is exactly one year old so I'd hope it didn't fail. the only reason I could think of (and im not sure if this could even do it) is the battery has gotten shorted momentarily in the past on accident for a couple seconds and created some sparks.

anyway It was showing 12.4 volts which I thought was an acceptable charge for a battery but I will try to get it 12.6 or so and try.
 
after 20 minutes on trickle charger I'm at 12.6 volts. I tried starting the car, same thing. just cranking... no start. looking closer at the multimeter this time, it only drops to 10.7 volts while cranking so that is normal.

things were working on and off and the problem got worse after putting the alternator back on but now its not even starting.

I wonder why its not starting now?
 
Not flooded?
Pull a plug wire, take an old plug attach to your favorite cylinder hold the plug on a good ground and crank a bit. (with insulated pliers)
Should have a crisp blue/white spark not yellow.
If no spark then you need to trouble shoot the ignition.
 
Not flooded?
Pull a plug wire, take an old plug attach to your favorite cylinder hold the plug on a good ground and crank a bit. (with insulated pliers)
Should have a crisp blue/white spark not yellow.
If no spark then you need to trouble shoot the ignition.
I don't think its flooded?
I just did the test and I'm getting a nice hot blue spark
 
Can you post a pic of the repair you made to the bulk head? I don't fully understand what you mean by adding spades. It's it poss something is shorting in the bulkhead now? 100 percent sure you got everything where it should go? Any melted terminals?

The not starting is odd, I was gonna say check voltage at the coil, but you say you have spark
 
Good. Try and hold the choke open slowly press the throttle halfway or more don't move it and try cranking it. Don't move the throttle between tries. If it's flooded it should clear and fire.
 
I soldered all the wires under dash and then added connectors in engine bay. I'm confident it's all correct, I was very careful labeling everything and the car started and ran perfectly for a minute or two in between periods of not working right. And then now it wont start at all. But it cranks with full power and I have spark. I dont think it's a fuel issue. Could it be ignition switch somehow?

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The rebuilt alternator says it has a lifetime warranty if I'm reading that correctly. Also Napa basically let's you return anything within 30 days.

Just trying to save you some money if a new/rebuilt alternator doesn't solve the problem. If you look at it from the store's view, what are they going to do with a used/installed alternator? Again, if your NAPA takes electrical parts back after they are used as a 'test' part, you will have lucked out. Me? I'd ask first...I wish you luck in your quest to solve this problem.
 
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