Check out of charging system

DanEC · #1 (**permalink**) 02-11-2013, 08:33 AM

Bob - when I briefly started my car (782) this weekend it appeared to be discharging before a coolant leak curtailed running it longer. My belt was not very snug and the battery was a little low from testing. I tightened the belt and charged the battery so maybe that will take care of it when I can try it again. I think the ammeter is hooked up right as turning on the lights shows it discharging. I didn't have the presence of mind to see if the ignition light was on.

This voltage regulator has a lot more leads than I'm used to on my old Plymouth - any hints to easily check the system out to pinpoint alternator vs regulator charging problems? I'm using a Powermaster stock type alternator.

thanks

DanEC · #2 (**permalink**) 02-11-2013, 08:50 AM

I should have noted that there are more leads connecting to the alternator also than the 2 leads/Alt and 2 leads/regulator on an old Chrysler system I recently trouble tested. Jumping leads between alternator and battery should tell me the system is charging if Voltage is around 14 - 14.5. If down around 12.5 volts I need to know which leads need to be checked to check the regulator field.

patrickt · #3 (**permalink**) 02-11-2013, 09:28 AM

There's not much to it. Here's a pic of the schematic. The only trick is that if the filament is out in your little red light, then you're not going to excite the regulator unless you have the little resistor. There's a lengthy thread on that from a few years back and I remember posting printouts from my automotive shop textbook from the 70's. It was still right on point, at least when it came to the ERA cars.

The first thing to look at is whether that little red light is on or off when the car is running. The nice thing about it being on is that you know it works, at least.

patrickt · #4 (**permalink**) 02-11-2013, 09:51 AM

IF, your light is OFF when the car is running, and IF you're only getting about 12.5 volts while it's running, and IF you are getting 12 volts to the A lead on the voltage regulator, then make these two cuts, and one jumper over, and that will help you diagnose your problem. Note that you must snip the wire lead to I on your voltage regulator (black asterisk) and you must snip the S lead from the voltage regulator as well (other black asterisk). You then jumper that snipped end of the voltage regulator side over to the the A wire just as I drew it in. Then fire up your engine and see if you get a nice 14 volts or so. Here's a pic I made for you on how you do it. This stuff is easy... you can do it.

DanEC · #5 (**permalink**) 02-11-2013, 10:46 AM

Thanks Patrick - not too sure about cutting into the harness. Hopefully it doesn't come to that. The red light works in that I know it lights when I turn the key on.

patrickt · #6 (**permalink**) 02-11-2013, 10:53 AM

Quote:

Originally Posted by DanEC

Thanks Patrick - not too sure about cutting into the harness. Hopefully it doesn't come to that. The red light works in that I know it lights when I turn the key on.

Then you're half way home. Pull the plug from the voltage regulator and jumper from the FIELD tang over to the POWER tang (first and third holes on the plug from left to right) and make sure you have 12v there when the ignition is on. Start the engine and gently rev it no higher than 1500 RPM or so. If you have a nice 14v, then the problem is the voltage regulator, if the voltage does not rise, then the alternator is bad or the connections over to it are bad.

DanEC · #7 (**permalink**) 02-11-2013, 11:29 AM

Quote:

Originally Posted by patrickt

Then you're half way home. Pull the plug from the voltage regulator and jumper from the FIELD tang over to the POWER tang (first and third holes on the plug from left to right) and make sure you have 12v there when the ignition is on. Start the engine and gently rev it no higher than 1500 RPM or so. If you have a nice 14v, then the problem is the voltage regulator, if the voltage does not rise, then the alternator is bad or the connections over to it are bad.

Perfect - this is what I need.

Dan

strictlypersonl · #8 (**permalink**) 02-11-2013, 12:36 PM

Note that Pat's technique is described in the troubleshooting supplement:
http://www.erareplicas.com/427man/wiring/wprimer.pdf

patrickt · #9 (**permalink**) 02-11-2013, 12:57 PM

Here's the thread I was talking about earlier: First Drive today - speedo and electrically issues / help? and here's the blurb from my old book talking about the need for the little red light to start the alternator charging (third paragraph of the first section):

DanEC · #10 (**permalink**) 02-11-2013, 07:37 PM

Quote:

Originally Posted by strictlypersonl

Note that Pat's technique is described in the troubleshooting supplement:
http://www.erareplicas.com/427man/wiring/wprimer.pdf

I hadn't run across this before - I could have used this a few weeks ago.

thanks

Dan

patrickt · #11 (**permalink**) 02-11-2013, 07:54 PM

Don't worry, the "my ERA won't charge" is the easiest electrical problem there is. Second only to "my horns won't blow."

DanEC · #12 (**permalink**) 02-12-2013, 06:19 AM

Quote:

Originally Posted by patrickt

Don't worry, the "my ERA won't charge" is the easiest electrical problem there is. Second only to "my horns won't blow."

My horns blow but one side of my turn signals don't work. I noticed a section in Bob's manual on that so I'll start there.

patrickt · #13 (**permalink**) 02-12-2013, 06:31 AM

Quote:

Originally Posted by DanEC

My horns blow but one side of my turn signals don't work. I noticed a section in Bob's manual on that so I'll start there.

Just trace the circuit back, starting at the "turn switch" side of the trailer relay, which is fastened to your steering column just over your knees. The only trick to that if the front turn signal bulb is bad (like with a blown filament), or if the circuit is "open" up there because of a broken wire or bad connection, then the entire side can fail to light up. The wiring is very simple, though; it's not nearly as complicated as today's cars.

DanEC · #14 (**permalink**) 02-16-2013, 12:09 PM

I finally got a replacement heater valve yesterday and sealed the cooling system back up to restart the motor. Geez - took UPS over a week and half to deliver it. Upon restarting the charging light is showing red. I used Bob's electrical primer manual to test the alternator and regulator. With the motor running I'm only getting 12.4 volts at the battery - same as with the motor off. I pulled the plug off of the regulator and jumpered from the power wire to the ground with the key on - 0 volts. Same thing from the ground terminal to ground. Checked the fuse for the yellow/red striped power wire. It appears fine. I made a jumper wire to connect the power wire and ground wire together in the regulator plug and re-started the engine. I first glanced at the ammeter gage and it was pegged all the way over on the charge side and I immediately shut the motor down.

My battery was getting pretty weak by this time - maybe that's why the ammeter pegged (?) Sound like the regulator?

I plugged the regulator back in securely and restarted and it's still showing no charge. Because one of the turn signals was not working the other day I decided to try them before killing the engine. The driver side works fine and the ammeter showing an expected fluctuation as it operates. When I turned on the passenger side the ammeter went wide - charging, discharging, bouncing all over. I tried it twice with the same results. I haven't had time to trouble shoot the turn signals yet but I will according to Bob's manual.

Thoughts? Bad regulator? Did I miss something?

I'm just not the best electrical guy. When I last changed the ice/water filter in our refrigerator the service light that shows green when the filter is good and eventually changes to yellow and red when they want you to replace it - went out. That was months ago - I figured I can live without it. Today said something about it to my wife and she opened the door and a minute later said - "there, its fixed." I said, how's that? She said "I just pushed the reset button in and held it for 3 seconds." I said great - there is not hope for me and the Cobra.

patrickt · #15 (**permalink**) 02-16-2013, 01:18 PM

There are five wires coming out of the harness to the voltage regulator. Four go to the plug and the solid black one has an eyelet for the ground to the regulator itself. Using your VOM, do this:

1) Place the + lead of the VOM on the positive side of your car's battery and the - lead of your VOM on the black eyelet. Do you have 12 volts? If not, there's a bad ground connection to the black wire.

2) With the key turned on, but not cranking, put the + lead of your VOM on the YELLOW/RED wire going to the voltage regulator and the - lead of your VOM on the black wire's eyelet. Do you have 12 volts?

3) If the answer to #2 was "No" then, just for the heck of it, turn your turn signals on, each way, and see if that makes the voltage go up and down on the YELLOW/RED wire like a flashing bulb would do. BTW, this should never happen.

Then report back.

DanEC · #16 (**permalink**) 02-17-2013, 09:15 AM

I jumped the positive cable connection at the starter relay to the gound on the voltage regulator and got 12.8 volts (I've had the charger on the battery).

I then unplugged the regulator, installed a jumper lead on the yellow wire and connected to the positive meter probe and turned the key on. I again got 12.7 volts.

I didn't try turning the flashers on since I had voltage.

Thoughts??

patrickt · #17 (**permalink**) 02-17-2013, 09:33 AM

Quote:

Originally Posted by DanEC

I jumped the positive cable connection at the starter relay to the gound on the voltage regulator and got 12.8 volts (I've had the charger on the battery).

I then unplugged the regulator, installed a jumper lead on the yellow wire and connected to the positive meter probe and turned the key on. I again got 12.7 volts.

I didn't try turning the flashers on since I had voltage.

Thoughts??

On the alternator, confirm that you have the big ORANGE wire connected to the BAT terminal, the BLACK wire grounding it, the BLUE/GREEN wire to the FIELD and the WHITE/BLACK wire to the stator. Then pull the plug on the voltage regulator and jumper between the first tang that has the BLUE/GREEN wire and the third tang that has the YELLOW/RED wire; do not plug the voltage regulator plug back in to the voltage regulator. Start the car and rev no high than 1500 RPM and view the VOM's voltage at the battery. Report back.

DanEC · #18 (**permalink**) 02-17-2013, 09:33 AM

Since the ammeter was showing a charge (pegged over with a partially discharged battery) with the power and field jumped together; and since the ground is good - it looks to me that per Bob's electrical primer publication, I have a bad voltage regulator. I took it out thinking it might be a mechanical one that I could check the points and gap inside but it's a sealed unit so I guess it's a non-mechanical unit.

patrickt · #19 (**permalink**) 02-17-2013, 09:36 AM

I'd like to hear the actual voltage reading with the jumper across the first and third tang of the voltage regulator plug and the engine running at 1500 RPM.

DanEC · #20 (**permalink**) 02-17-2013, 10:14 AM

Patrick, I double checked the connections at the alternator. These rebuilt alternators don't have any legible print left on the case but I hooked everything up per ERA's schematic. I made sure the Field and Stator wires went to the connections with respect to distance from the shaft per ERA's manual.

I ran that test with gounding the two leads on the regulator plug yesterday and got a full charge on the ammeter. I'm going to re-start it after bit and will run it again but I don't think the results will be any different.

Thanks

Dan