Previous Thread
Next Thread
Print Thread
Overcharging problem - question #1198327
03/17/12 11:09 AM
03/17/12 11:09 AM
Joined: Jan 2003
Posts: 4,296
Chicago, IL
TonyS451 Offline OP
master
TonyS451  Offline OP
master

Joined: Jan 2003
Posts: 4,296
Chicago, IL
Hey Guys - Have a 67 Coronet wagon with a overcharging problem. Tried 2 new voltage regulators, 2 alternators, new engine wiring harness, sanded down mating surface of voltage regulator to ensure a good ground (with strap to engine) and still overcharging. It will pin the gauge needle to the charge side (18v) on aftermarket gauge and does the same with the factory dash gauge. It has also been confirmed on a auxillary gauge that it is in fact overcharging.

Havn't found any obvious wiring mixups, so I'm a little stumped as to why I still have an overcharging issue. Would it be easier to just get an internally regulated alternator, or is that just a band aid for a potential wiring problem?

What are your thoughts? Thanks


2 kids and a dog
Re: Overcharging problem - question [Re: TonyS451] #1198328
03/17/12 11:17 AM
03/17/12 11:17 AM
Joined: Feb 2003
Posts: 8,671
A
Andrewh Offline
master
Andrewh  Offline
master
A

Joined: Feb 2003
Posts: 8,671
well based on what you replaced, the bulkhead connector would be the next logical place to look.

but lets backtrack a little and see if any of that was necessary.

first what is the sensing voltage to the voltage reg with the key in run?

next what does your battery read with the car off as well?

use the negitive of the battery as the ground for both, then just incase there is a difference, use the firewall where your vr is grounded and see what it reads as well.

If they are not equal, the trace back to the bulk head and read on the engine side and then the interior side and see what the readings are with the car in run.

I bet you find a difference there.

feets car saw over 2 volts difference and I wired up a relay instead to power the vr and balast and it worked fine after that.

Re: Overcharging problem - question [Re: TonyS451] #1198329
03/17/12 11:39 AM
03/17/12 11:39 AM
Joined: Jan 2003
Posts: 27,728
places
7
79powerwagon Offline
Too Many Posts
79powerwagon  Offline
Too Many Posts
7

Joined: Jan 2003
Posts: 27,728
places
I too had an overcharging issue, tried several new VR trying to find out the problem. Someone here asked if I was using a Mopar piece or a Wells (or other aftermarket unit). I was using aftermarket. They suggested I use a real Mopar, and the problem went away and never returned.

Just another idea.

Re: Overcharging problem - question [Re: TonyS451] #1198330
03/17/12 11:40 AM
03/17/12 11:40 AM
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
R
RapidRobert Offline
Circle Track
RapidRobert  Offline
Circle Track
R

Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
Wiring prob. Disconnect ALL field wires then use jumper wires with alligator clips to connect batt positive to reg "ign". Jump connect reg "field" to alt field terminal. You're sure the alt/reg are grounded to batt neg properly. See if it behaves now & if so that'll confirm that it is a wiring prob. If not then the alt or the reg (more likely) is it. mechanical or electronic reg? Could have gotten a bad reg. If you confirm it is wiring then replace 1 jumper at a time with its OE lead till you find the culprit. Do the one at a time wiring changes with the eng off. I'm assuming your batt is fully charged and the large cables/batt terminals (positive an neg circuits) are cleaned. Sure sounds like a bad reg, something is full fielding it. EDIT do not go w an internally regulated alt

Last edited by RapidRobert; 03/17/12 11:46 AM.

live every 24 hour block of time like it's your last day on earth
Re: Overcharging problem - question [Re: Andrewh] #1198331
03/17/12 11:56 AM
03/17/12 11:56 AM
Joined: Jan 2003
Posts: 4,296
Chicago, IL
TonyS451 Offline OP
master
TonyS451  Offline OP
master

Joined: Jan 2003
Posts: 4,296
Chicago, IL
Quote:

well based on what you replaced, the bulkhead connector would be the next logical place to look.

but lets backtrack a little and see if any of that was necessary.

first what is the sensing voltage to the voltage reg with the key in run?

next what does your battery read with the car off as well?

use the negitive of the battery as the ground for both, then just incase there is a difference, use the firewall where your vr is grounded and see what it reads as well.

If they are not equal, the trace back to the bulk head and read on the engine side and then the interior side and see what the readings are with the car in run.

I bet you find a difference there.

feets car saw over 2 volts difference and I wired up a relay instead to power the vr and balast and it worked fine after that.




thanks Andrew, I will check this out...


2 kids and a dog
Re: Overcharging problem - question [Re: RapidRobert] #1198332
03/17/12 11:59 AM
03/17/12 11:59 AM
Joined: Jan 2003
Posts: 4,296
Chicago, IL
TonyS451 Offline OP
master
TonyS451  Offline OP
master

Joined: Jan 2003
Posts: 4,296
Chicago, IL
Quote:

Wiring prob. Disconnect ALL field wires then use jumper wires with alligator clips to connect batt positive to reg "ign". Jump connect reg "field" to alt field terminal. You're sure the alt/reg are grounded to batt neg properly. See if it behaves now & if so that'll confirm that it is a wiring prob. If not then the alt or the reg (more likely) is it. mechanical or electronic reg? Could have gotten a bad reg. If you confirm it is wiring then replace 1 jumper at a time with its OE lead till you find the culprit. Do the one at a time wiring changes with the eng off. I'm assuming your batt is fully charged and the large cables/batt terminals (positive an neg circuits) are cleaned. Sure sounds like a bad reg, something is full fielding it. EDIT do not go w an internally regulated alt




79powerwagon - Both regulators I tried were MP pieces.

Robert - It is an electronic regulator, battery is fully charged, and battery/cables are all new and clean. I will check into your idea as well. Thanks


2 kids and a dog
Re: Overcharging problem - question [Re: TonyS451] #1198333
03/17/12 04:49 PM
03/17/12 04:49 PM
Joined: Jan 2003
Posts: 25,757
Rio Linda, CA
John_Kunkel Offline
Too Many Posts
John_Kunkel  Offline
Too Many Posts

Joined: Jan 2003
Posts: 25,757
Rio Linda, CA

I know the OP states it's a '67 but does it have the original single field connection alternator or has it been upgraded to a dual field connection alternator?


The INTERNET, the MISinformation superhighway
Re: Overcharging problem - question [Re: John_Kunkel] #1198334
03/17/12 05:35 PM
03/17/12 05:35 PM
Joined: Sep 2007
Posts: 14,889
up yours
Supercuda Offline
About to go away
Supercuda  Offline
About to go away

Joined: Sep 2007
Posts: 14,889
up yours
Quote:


I know the OP states it's a '67 but does it have the original single field connection alternator or has it been upgraded to a dual field connection alternator?




Exactly,

Original single wire field setup would be troubleshot differently than the dual wire setup.


They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.
Re: Overcharging problem - question [Re: John_Kunkel] #1198335
03/17/12 05:39 PM
03/17/12 05:39 PM
Joined: Jan 2003
Posts: 4,296
Chicago, IL
TonyS451 Offline OP
master
TonyS451  Offline OP
master

Joined: Jan 2003
Posts: 4,296
Chicago, IL
Quote:


I know the OP states it's a '67 but does it have the original single field connection alternator or has it been upgraded to a dual field connection alternator?




It has a dual field alternator fwiw, it now has a factory electronic ignition regulator with the 2 pin plug connector. When I ordered engine wiring from Year One for electronic ignition it comes wired for later style voltage reg, 4 prong ballast, and has a plug for the ecu.


2 kids and a dog
Re: Overcharging problem - question [Re: TonyS451] #1198336
03/17/12 05:52 PM
03/17/12 05:52 PM
Joined: Dec 2010
Posts: 1,035
Missouri U.S.A.
7
71yelladustr Offline
super stock
71yelladustr  Offline
super stock
7

Joined: Dec 2010
Posts: 1,035
Missouri U.S.A.
What does it charge with the voltage regulator unplugged? If it is still overcharging even while unplugged, the green field wire to the regulator is shorted to ground.


392 gen III hemi on E-85 727 trans Dana 60
10.02@134
Re: Overcharging problem - question [Re: 71yelladustr] #1198337
03/17/12 06:04 PM
03/17/12 06:04 PM
Joined: Jan 2003
Posts: 4,270
Morrow, OH
markz528 Offline
master
markz528  Offline
master

Joined: Jan 2003
Posts: 4,270
Morrow, OH
Check the voltage regulator ground. If the ground is poor it will think the voltage is lower than it really is.


67 Coronet 500 9.610 @ 139.20 mph
67 Coronet 500 (street car) 14.82 @ 94 mph
69 GTX (clone) - build in progress......
Re: Overcharging problem - question [Re: markz528] #1198338
03/17/12 07:13 PM
03/17/12 07:13 PM
Joined: Jan 2003
Posts: 5,875
communist bloc of new jersey
J
jamesc Offline
master
jamesc  Offline
master
J

Joined: Jan 2003
Posts: 5,875
communist bloc of new jersey
on the newer two wire charging system the regulator controls the ground to vary the output. the field circuit makes a magnetic field in the rotor of the alternator, by controlling the strength of this field it controls the output. one side of the field sees ignition positive voltage and the regulator controls the ground side to vary the output. if the ground side is shorted to ground anywhere it will produce maximum output.

Re: Overcharging problem - question [Re: jamesc] #1198339
03/17/12 07:31 PM
03/17/12 07:31 PM
Joined: Jan 2003
Posts: 25,757
Rio Linda, CA
John_Kunkel Offline
Too Many Posts
John_Kunkel  Offline
Too Many Posts

Joined: Jan 2003
Posts: 25,757
Rio Linda, CA
Disconnect the ground control field wire (usually green) from the alternator terminal, if it stops overcharging the wiring is the problem. Check the control wire for a short to ground between the alternator and regulator.

If it still overcharges with the wire off there is an internal short to ground.


The INTERNET, the MISinformation superhighway
Re: Overcharging problem - question [Re: John_Kunkel] #1198340
03/17/12 11:23 PM
03/17/12 11:23 PM
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
R
RapidRobert Offline
Circle Track
RapidRobert  Offline
Circle Track
R

Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
on the 2 field circuit system you pretty much just need switched 12V via the blue wire circuit to (1) the the top terminal in the VR triangle connector with the "top" being with the triangle being "up" like a pyramid and (2) T ing off of it to either one of the male alt field terminal (blue wire). Then the green wire runs from the "side" VR terminal to the other alt male field terminal. Is that what you currently have wired? That's all you need for the field circuit to make it charge


live every 24 hour block of time like it's your last day on earth
Re: Overcharging problem - question [Re: John_Kunkel] #1198341
03/18/12 07:13 PM
03/18/12 07:13 PM
Joined: Jan 2003
Posts: 4,296
Chicago, IL
TonyS451 Offline OP
master
TonyS451  Offline OP
master

Joined: Jan 2003
Posts: 4,296
Chicago, IL
Quote:

Disconnect the ground control field wire (usually green) from the alternator terminal, if it stops overcharging the wiring is the problem. Check the control wire for a short to ground between the alternator and regulator.

If it still overcharges with the wire off there is an internal short to ground.




OK, John - I disconnected the green field wire from the alternator and the overcharging stops. The charging stops all together. So, do you think the short is somewhere between the alternator and the V regulator? thanks


2 kids and a dog
Re: Overcharging problem - question [Re: TonyS451] #1198342
03/18/12 08:03 PM
03/18/12 08:03 PM
Joined: Feb 2003
Posts: 8,671
A
Andrewh Offline
master
Andrewh  Offline
master
A

Joined: Feb 2003
Posts: 8,671
that depends.
does that line read some small voltage, or ground?

if it reads ground, you have a break in the line somewhere and you need to trace it back to the vr from the alt.

if it reads voltage of some sort, then you need to check voltage on the other line plugged into the alt and see if it reads voltage or ground.

again, ground, would mean a break, voltage on both means bad vr, or bad voltage to the vr as I said in the begining.

Re: Overcharging problem - question [Re: TonyS451] #1198343
03/18/12 08:26 PM
03/18/12 08:26 PM
Joined: Jan 2003
Posts: 5,875
communist bloc of new jersey
J
jamesc Offline
master
jamesc  Offline
master
J

Joined: Jan 2003
Posts: 5,875
communist bloc of new jersey
that proves there isn't an internal short. that line could be shorted to ground, the VR may not be seeing the +12 ignition, the VR could be bad or have a bad ground. this is a very simple circuit, here's a link mopar charging system

Re: Overcharging problem - question [Re: jamesc] #1198344
03/19/12 05:21 PM
03/19/12 05:21 PM
Joined: Jan 2003
Posts: 25,757
Rio Linda, CA
John_Kunkel Offline
Too Many Posts
John_Kunkel  Offline
Too Many Posts

Joined: Jan 2003
Posts: 25,757
Rio Linda, CA
If it's overcharging, both the regulator and alternator are getting battery voltage.

Since both the alternator and the regulator have been changed twice it's pretty safe to say there is a short in the field wire between the alternator and the regulator; most common place is where it runs along the valve cover.


The INTERNET, the MISinformation superhighway
Re: Overcharging problem - question [Re: John_Kunkel] #1198345
03/20/12 01:04 AM
03/20/12 01:04 AM
Joined: Sep 2003
Posts: 159
Woodward, PA
7
75DART440 Offline
member
75DART440  Offline
member
7

Joined: Sep 2003
Posts: 159
Woodward, PA
I once saw a parts store reman alternator that was missing the small insulating washers under the field terminals. It overcharged untill it cooked the fuse link and the alternator.


Buy a Hybrid!! I need your gas!!! Currently spending $1,000 a month to feed the Hemis!! Looking for that elusive CHEAP 71-72 Plymouth B-body 2 door OR 71-72 Coronet 4 door!!!
Re: Overcharging problem - question [Re: 75DART440] #1198346
03/20/12 01:43 AM
03/20/12 01:43 AM
Joined: May 2009
Posts: 508
Cincinnati, Ohio
S
superbeedave Offline
mopar
superbeedave  Offline
mopar
S

Joined: May 2009
Posts: 508
Cincinnati, Ohio
Just from my experience I had some 13 years ago! After I bought my 69 Superbee I bought a carter 625 carb. and Mopar electronic ignition. Two or so years later I started noticing battery acid running out of my battery. I put voltage meter on for the first time and it was charging 15.2 volts. And this was 10 or so years ago. I had this overcharging problem for some eight years. Man, you talk about frustrations! I ended up going to a 70's style charging system and that brought it down a little but still had the problem until I bought a new 650 AVS carburetor two years ago. After I had my engine rebuilt it was again up to 15.2 volts. Well when I started going over the instructions I read where it said DO NOT!! hook the hot wire from the electric choke to positive side of coil! Well for those years I had it hooked up to the coil but when I hooked up the new carb. choke wire to key on pos. wire my voltage came down to normal, after all those years! That was my problem, go figure! So I'm just saying do you have an electric choke and if you do is it hooked up to either your ballast resistor pos. side or coil side?







Powered by UBB.threads™ PHP Forum Software 7.7.1