still having problems, need advice please

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oldmusclelover

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67 dart with 69 340 engine, fixed all wiring from bulkhead (including bulkhead packard clips), cleaned every ground I could find, have added wire around and headlight relays (thanks Ron). here's the numbers:

new battery and new alternator (50 amp square back Chrysler).
tests:
12.67 at battery before starting.
start engine, at idle:
14.34 at battery
14.30 at starter relay
red from battery 14.20 at bulkhead
coil positive 11.26
ballast 13.7
alternator stud 14.6 (goes down as engine warms up)
alternator stud warm engine 13.91/13.98
when electric fan stops 13.85/13.75

negative battery post to alternator housing 6.0V (5.1 @ 1500 rpms)
negative battery post to block 0
negative battery post to ground strap at block/firewall 5.5V (same at 1500 rpms)
negative battery post to ground wire at frame 3.0 V (same at 1500 rpms)
negative battery post to ground wire at block 0

then ran high idle (1500 rpms)

13.22 at battery
13.41 at alternator stud
13.2 at starter relay
13.22 red at bulkhead
coil positive 11
ballast 12.95

then high idle with load of headlights, wipers, heater fan, flashers, and radiator fan cycling (did put both power to fan with relays, along with switch to starter relay so it would continue to cool after engine is shut off with key, is that alright?).
battery 13.16
ballast 12.24
alternator stud 13.10
then car died before I could finish.
checked battery quickly while fan was running 12.38, when stopped 12.59
no fuses blew, 40 in black from alt, 30 in red from battery, 40 in wire around (sorry Ron, cut myself short with the wrapping and had to add a fuse in the fusible link).
started engine again and battery was 13.10, and engine did not start easily.
the previous night I was doing checks and would only reach in the window and hit the key and it would start immediately.

any help appreciated, if you need other readings, just let me know.
thanks to all that have gotten me this far, it has been a long journey to be sickened by having continuous problems (whining over). thanks again to all.
 
When you are taking your battery voltage measurements , are probing the negative post of the battery or just the cable clamp?

Negative battery post to alternator housing: 6.0v.
That's bad. Should be really low, .5v or so.
 
Coil positive post, engine running , should be: 6v.

Voltage goes through ballast for a voltage drop. You probably know this. Sometimes stating the obvious can clarify troubleshooting. Helps get folks on the same page.
 
'67 Dart. This would still be the mechanical regulator and with one Field lead on the alternator permanently grounded?


negative battery post to alternator housing 6.0V (5.1 @ 1500 rpms)
negative battery post to block 0

That tells me your alternator housing is poorly grounded to the engine block.
 
Agreed, run a wire from the alt ground stud to block.

Sorry I didn't answer your PM. Lots of not so great stuff going on here. I apologize.
 
When you are taking your battery voltage measurements , are probing the negative post of the battery or just the cable clamp?

Negative battery post to alternator housing: 6.0v.
That's bad. Should be really low, .5v or so.
I'm going right into the lead post, not the clamp. I know, not good, right? any ideas? thanks
 
Coil positive post, engine running , should be: 6v.

Voltage goes through ballast for a voltage drop. You probably know this. Sometimes stating the obvious can clarify troubleshooting. Helps get folks on the same page.
I only know it because of the people here, but thought 8V was the number I was shooting for, oops
 
'67 Dart. This would still be the mechanical regulator and with one Field lead on the alternator permanently grounded?


negative battery post to alternator housing 6.0V (5.1 @ 1500 rpms)
negative battery post to block 0

That tells me your alternator housing is poorly grounded to the engine block.
negative, on the reg. have switched over to dual field with regulator update as well. have checked that a couple times as well, all is correct. I took a file to the block where it connects, cleaned the threads, and bolt. thought about running a ground wire between casing and block, but would that be a ground loop?
 
Agreed, run a wire from the alt ground stud to block.

Sorry I didn't answer your PM. Lots of not so great stuff going on here. I apologize.
no apologies necessary :) I'll run that ground. now, since I have the 10 gauge wire from alt to bulkhead, would another 10 gauge wire be sufficient for the ground?
 
Checking from the actual battery post is the way to do it. That's what the battery "sees". So you're good there.

Nice that you are checking grounds to Neg. post. Most folks ignore that part of troubleshooting.

8v on + coil post is o.k. In actuality, it's a 6v coil. It'll run on 12v but, not for a long time.

Your regulator may need to have the case grounded. I've got a '75 Dodge, ran a ground wire from the mounting bolt of the voltage regulator all the way to the negative battery cable ground. That did make a difference in voltage output. But, I've got rust problems on my vehicle that affects grounds.

What type of meter are you using for this?
Analog, digital Fluke, etc...?
Reason I ask is because with an analog there is a test you can do that can't be done with a digital.(least it never worked that way for me).

Dual field regulators (Mopar) run a constant 12v to one side of the alternator field. Is that what you are getting?
 
Checking from the actual battery post is the way to do it. That's what the battery "sees". So you're good there.

Nice that you are checking grounds to Neg. post. Most folks ignore that part of troubleshooting.

8v on + coil post is o.k. In actuality, it's a 6v coil. It'll run on 12v but, not for a long time.

Your regulator may need to have the case grounded. I've got a '75 Dodge, ran a ground wire from the mounting bolt of the voltage regulator all the way to the negative battery cable ground. That did make a difference in voltage output. But, I've got rust problems on my vehicle that affects grounds.

What type of meter are you using for this?
Analog, digital Fluke, etc...?
I removed the paint on the firewall and the back of the voltage regulator, both sides, so I'm hoping it's grounded. also have the ground strap from the engine to the firewall on one of the bolts. have a Klein multi-meter, digital. and a fluke clamp, also digital.
 
engine block to battery -
engine block to body
you got a bad ground or you are missing a cable
 
engine block to battery -
engine block to body
you got a bad ground or you are missing a cable
Brian, I have 2/0 from battery to block, 2/0 from block to frame, and have cleaned both with file and sandpaper, 10 gauge braided strap from block to firewall, all clean. sounds like a bad ground to me too, but where?
 
I have no idea what the problem is.. these people helping you out know far more than I do. Just wanted to say that this is what makes this site great. People helping out others. Hope ya get it squared away!
 
you might look into running the alternator power directly to the starter relay or the battery and bypass the ammeter and bulkhead going directly to the starter relay . at least cut down the load on the dash harness wiring and give the alternator all you can directly
 
I have no idea what the problem is.. these people helping you out know far more than I do. Just wanted to say that this is what makes this site great. People helping out others. Hope ya get it squared away!
thanks RSie, you are so right! great knowledgeable people, besides being good hearts and willing. you know what they say "two heads are better than one" ;)
 
you might look into running the alternator power directly to the starter relay or the battery and bypass the ammeter and bulkhead going directly to the starter relay . at least cut down the load on the dash harness wiring and give the alternator all you can directly
thanks dozer, have already done those. my mistake by not putting that in the original thread. but, if I hadn't, I would be doing it.
 
Checking from the actual battery post is the way to do it. That's what the battery "sees". So you're good there.

Nice that you are checking grounds to Neg. post. Most folks ignore that part of troubleshooting.

8v on + coil post is o.k. In actuality, it's a 6v coil. It'll run on 12v but, not for a long time.

Your regulator may need to have the case grounded. I've got a '75 Dodge, ran a ground wire from the mounting bolt of the voltage regulator all the way to the negative battery cable ground. That did make a difference in voltage output. But, I've got rust problems on my vehicle that affects grounds.

What type of meter are you using for this?
Analog, digital Fluke, etc...?
Reason I ask is because with an analog there is a test you can do that can't be done with a digital.(least it never worked that way for me).

Dual field regulators (Mopar) run a constant 12v to one side of the alternator field. Is that what you are getting?
you might be on to something my friend, as I just checked ohms on both and they look to be......let's say, toast. car won't even start now, so made me check the coil, bad numbers. then, since the reading was so high, I checked the ballast, bad numbers. just sent my GF to get the parts, we'll see if that is it. it sure seems to be a bad ground, but I have checked, and checked, and checked.
 
Make a jumper lead with alligator clips. Clip one to the alternator frame and the other to the Neg. battery post. Your initial 5v reading across those is significant.

Your first post indicated that as the engine warmed up, voltage dropped. This tells me that you have a high resistance connection and as current flows through it, resistance goes higher, voltage goes down.

Or the alternator belt is slipping. Sometimes they don't make a noise.
 
Make a jumper lead with alligator clips. Clip one to the alternator frame and the other to the Neg. battery post. Your initial 5v reading across those is significant.

Your first post indicated that as the engine warmed up, voltage dropped. This tells me that you have a high resistance connection and as current flows through it, resistance goes higher, voltage goes down.

Or the alternator belt is slipping. Sometimes they don't make a noise.
I don't think the belt is slipping, but after putting a ground wire on the alternator, my reading is zero. zero across the board, no resistance. replaced the coil and ballast resistor and it fired right up. now, I'm wondering if I also screwed the regulator? still getting low readings from the battery and alternator post. 12.33 do you think I may have hurt the regulator?
 
Sorry for the late response, the hurricane was causing erratic power fluctuations here at the house. So, I turned off the computer for a day or so.

12.3 volts, engine running as you know is bad.
14.0 volts +/- .2 volts is target value for alternator output.

Engine off, ignition key in Run position:
One field lead to the alternator should be battery voltage. (12.3 or even about 11.5 is o.k.)
Just probe the back of the slip on connector.
We'll call that F1.
Do you have battery voltage at that connector?
____________________
The other field lead goes back to the regulator.
Call it F2.
Disconnect that wire. Leave it disconnected.
With your ohm meter, measures ohms on that wire.
(it goes back to the regulator)
Should be a low ohm reading. .5 or so.
____________
If you have battery voltage going to F1 and a ground or nearly so on the F2 wire going back to the regulator. Then the alternator is the problem or it's case ground.
_____________________
Connect you multi meter to the battery posts to monitor battery voltage.
Start the engine. Idle rpm, only.
Clip a jumper on the alternator field terminal(F2) you just disconnected the wire from. For a brief moment, ground the other end of that jumper wire to the block. Just touch it.
You should get maximum alternator output and probably 15 volts at your meter. (sensitive equipment like stereoes, if "on" could get fried.
___________
If that checks o.k., then you have a bad voltage regulator. (or the wires going to and from it).
 
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FWIW never do a resistance check with power on the circuit it will give you a false reading. I like to disconnect the battery if I am doing resistance checks on any wires.
 
FWIW never do a resistance check with power on the circuit it will give you a false reading. I like to disconnect the battery if I am doing resistance checks on any wires.
That is often true with digital volt meters. However, to do the test just described, the ignition switch will have to be "on" for the regulator to sense something. This is where an analog meter works or a test light.

Could disconnect both F1 and F2 wires. Probe those wires with a test light. The light should burn brightly. Seems a lot of people don't use test lights, anymore. Maybe I should have asked if the OP has one?
 
I work on newer cars and test lights are obsolete for them, but you could still have a resistance in the connection and the test light will still light, I have used a test light and a volt meter on the same circuit at the same time to see a voltage drop and that works were a volt meter alone wont.
 
Sorry for the late response, the hurricane was causing erratic power fluctuations here at the house. So, I turned off the computer for a day or so.

12.3 volts, engine running as you know is bad.
14.0 volts +/- .2 volts is target value for alternator output.

Engine off, ignition key in Run position:
One field lead to the alternator should be battery voltage. (12.3 or even about 11.5 is o.k.)
Just probe the back of the slip on connector.
We'll call that F1.
Do you have battery voltage at that connector?
____________________
The other field lead goes back to the regulator.
Call it F2.
Disconnect that wire. Leave it disconnected.
With your ohm meter, measures ohms on that wire.
(it goes back to the regulator)
Should be a low ohm reading. .5 or so.
____________
If you have battery voltage going to F1 and a ground or nearly so on the F2 wire going back to the regulator. Then the alternator is the problem or it's case ground.
_____________________
Connect you multi meter to the battery posts to monitor battery voltage.
Start the engine. Idle rpm, only.
Clip a jumper on the alternator field terminal(F2) you just disconnected the wire from. For a brief moment, ground the other end of that jumper wire to the block. Just touch it.
You should get maximum alternator output and probably 15 volts at your meter. (sensitive equipment like stereoes, if "on" could get fried.
___________
If that checks o.k., then you have a bad voltage regulator. (or the wires going to and from it).
iScamp, I have read this somewhere before, and as you say, just enough time to get a reading. I will give that a shot. I did do a drop test on the battery side and found that from my pos battery post to the pos (run) wire at ballast I have 1.28 volts, which I know is bad, so I will have to do some more cleaning on the other side of the firewall. when I disconnected the ammeter, I just put a bolt through the eyelets. maybe I should go back there and connect them better? or do you think the bolt is sufficient for now? I don't think that is where my drop is coming from, but definitely could add to the problem. going to run a negative side test as well and see what that reads. I will post all readings in a while, just heading out there now. thanks again for your help
 
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