charging system issue

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PanGasket

PanGasket

has cork sides
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Here's what's going on guys

My charging gauge reads at right inbetween D and the center and sticks there like glue no matter the RPM and my lights seem a good bit dimmer. Also, my passenger side turn signal blinks really really slow and I very recently replaced my VR.

Anybody got any clue on this? I know my battery is good.
 
Make a couple of "quick checks" and if need be we'll get deeper from there

1--Make absolutely sure the regulator is grounded. Scrape the mount/ flange clean and use star washers.

2--Work the regulator connector in/ out several times, and visually inspect for corrosion, other damage.

3--Key on, engine off, use a test lamp or meter to check the blue wire connected to one of the two field wires. Should get a bright light / same as battery voltage.

4--Remove green field wire at alternator, use a clip lead to ground the disconnected alternator terminal. In dim light you should be able to see a small spark as you connect/ disconnect the wire

5--Start the engine, bring up RPM and see if it shows a charge. If it does, you either have a wiring problem in the regulator circuit, or a bad regulator.

If it does not charge, and if you DID notice a spark at the field, hook a voltmeter to the alternator output stud. With the engine running fast, the voltage should be up around 14, but not really high. If voltage is really high, way over 16--20, etc, you have a bad connection in the alternator main output wire in the path to the battery.

If voltage is low, "same as battery" regardless of RPM, you most likely have a bad alternator.

Simplified diagram below:

The "I" terminal of the regulator receives switched 12V ignition voltage, the green wire from the regulator to the alternator controls "the amount of ground" at the alternator field

When you remove the green (F) wire and ground that alternator field terminal, you are causing full field current to flow from the ignition (blue field) through the field magnet, to ground (clip lead in place of green wire)

Dual_Field_Alternator_Wiring.jpg
 
67Dart273 said:
Make a couple of "quick checks" and if need be we'll get deeper from there

1--Make absolutely sure the regulator is grounded. Scrape the mount/ flange clean and use star washers.

2--Work the regulator connector in/ out several times, and visually inspect for corrosion, other damage.

3--Key on, engine off, use a test lamp or meter to check the blue wire connected to one of the two field wires. Should get a bright light / same as battery voltage.

4--Remove green field wire at alternator, use a clip lead to ground the disconnected alternator terminal. In dim light you should be able to see a small spark as you connect/ disconnect the wire

5--Start the engine, bring up RPM and see if it shows a charge. If it does, you either have a wiring problem in the regulator circuit, or a bad regulator.

If it does not charge, and if you DID notice a spark at the field, hook a voltmeter to the alternator output stud. With the engine running fast, the voltage should be up around 14, but not really high. If voltage is really high, way over 16--20, etc, you have a bad connection in the alternator main output wire in the path to the battery.

If voltage is low, "same as battery" regardless of RPM, you most likely have a bad alternator.

Simplified diagram below:

The "I" terminal of the regulator receives switched 12V ignition voltage, the green wire from the regulator to the alternator controls "the amount of ground" at the alternator field

When you remove the green (F) wire and ground that alternator field terminal, you are causing full field current to flow from the ignition (blue field) through the field magnet, to ground (clip lead in place of green wire)

Dual_Field_Alternator_Wiring.jpg
Click to expand...
Thank you so very much:cheers:. This seems pretty simple enough. My other thought is belt slip perhaps.
 
Belt should be easy to check. Post back with results.
 
didn't get a chance today. I rolled over out of bed to be told I was supposed to go to my sister's house and wait for the septic tank guy to come. well, he cancelled and nobody told me so I sat there and wasted 4 hours waiting for this guy. but I did manage to notice something else. my system charges fine when nothing is being used but the moment the headlights turn on it drops to where I said in my previous post and when no headlights and just turn signals, I watch the gauge fluctuate with every blink.
 
That of course indicates it's working somewhat. Very first thing I'd check is the belt.

Get a voltmeter and make some checks

Get the engine running at a good fast idle, and check voltage right at the battery, and also at the alternator output stud.

Make these checks with all loads off, (lights, etc) and then again with loads on, heater, lights

If the belt is not slipping, and if the voltage at the alternator stud is no more than a volt or so higher than battery voltage, and of course depending on what the battery volt. reads, sounds like an alternator that is only partly working.
 
67Dart273 said:
That of course indicates it's working somewhat. Very first thing I'd check is the belt.

Get a voltmeter and make some checks

Get the engine running at a good fast idle, and check voltage right at the battery, and also at the alternator output stud.

Make these checks with all loads off, (lights, etc) and then again with loads on, heater, lights

If the belt is not slipping, and if the voltage at the alternator stud is no more than a volt or so higher than battery voltage, and of course depending on what the battery volt. reads, sounds like an alternator that is only partly working.
Click to expand...

if the alternator turns out to be bad, should I rebuild.it or find a new.one? could.you recommend a good.kit in case it is?
 
You can't buy many "rebuild" parts anymore. I have a mid '70's "squareback" in my 67, and in three tries to get the local NAPA to order a brush set, I had to tear into two boxes, rob parts from both to make one good set, then turn what was left in as "misboxed --defective."

You can buy a so called rebuilt from any parts store, but make damn sure they give you a square back NOT a "round" back.

Other than that, junkyard, which of course is iffy, or adapt something later. Many guys have gone Delco/ Denso etc.

Do not under any circumstances accept the one on the left

squareroundcomp.jpg
 
yeah, my truck has a square back. that really is shitty that you can't get a rebuild kit for one. Im sure they rape you on the rebuilt ones too
 
hey Del, how do I measure the voltage at the output stud? just one probe on the stud and one to ground correct? and I threw a new belt on today so def no belt slip
 
I'd do this two ways. What you are trying to determine is if there is a poor connection in the path between the alternator and the battery.

Make this check with engine running "to simulate" low to med. cruise RPM, and with battery "normalized"

Make this check first with no loads, then again with headlights, heater, etc turned on.

1--First way is to measure battery voltage to ground, then measure from alternator stud to ground, and subtract the difference

2--The "direct" way is to put one probe of your meter on the alternator stud, and the other probe onto the battery positive post. You are hoping for a low reading, the lower the better. "Much more" than a volt or two means there is a problem connection. Less is better.
 
67Dart273 said:
I'd do this two ways. What you are trying to determine is if there is a poor connection in the path between the alternator and the battery.

Make this check with engine running "to simulate" low to med. cruise RPM, and with battery "normalized"

Make this check first with no loads, then again with headlights, heater, etc turned on.

1--First way is to measure battery voltage to ground, then measure from alternator stud to ground, and subtract the difference

2--The "direct" way is to put one probe of your meter on the alternator stud, and the other probe onto the battery positive post. You are hoping for a low reading, the lower the better. "Much more" than a volt or two means there is a problem connection. Less is better.
Click to expand...
and just to make sure, I want to have my meter set to AC, not DC, correct? sorry I am such a novice at electrical. atleast I know somewhat of a minute percent lol
 
NOPE, DC. If it does not have an "auto range" switch, start on a fairly high DC setting, like 20 volts or more, and if you are doing the "2" test, move the selector down until you get a good usable reading.

I know you may not understand, but "2" just gives you a direct readout of "1."

What you are doing here, is, let's say there is a REAL poor connection where the black alternator wire goes through the bulkhead.

You might perform test "1" and read 18V jumping around at the alternator stud, but only 13.5--14 at the battery. This means you are losing MORE than 4 volts (in this case) between the alternator and the battery.

Now this reading will CHANGE with load current. That is, if all the alternator is doing at the time, is keeping the ignition going, and NOT charging the battery (because it's "up) and NOT running lights, heater, etc, there will be VERY LITTLE current (amps, or amperage) in that line with the (supposed) bad connection.

In that case, the two voltage readings will become CLOSER together. But if you put a load on, turn on all the lights, stereo (crank it UP) the heater, etc, this reading will start to go UP because more amperage is now being drawn.
 
67Dart273 said:
NOPE, DC. If it does not have an "auto range" switch, start on a fairly high DC setting, like 20 volts or more, and if you are doing the "2" test, move the selector down until you get a good usable reading.

I know you may not understand, but "2" just gives you a direct readout of "1."

What you are doing here, is, let's say there is a REAL poor connection where the black alternator wire goes through the bulkhead.

You might perform test "1" and read 18V jumping around at the alternator stud, but only 13.5--14 at the battery. This means you are losing MORE than 4 volts (in this case) between the alternator and the battery.

Now this reading will CHANGE with load current. That is, if all the alternator is doing at the time, is keeping the ignition going, and NOT charging the battery (because it's "up) and NOT running lights, heater, etc, there will be VERY LITTLE current (amps, or amperage) in that line with the (supposed) bad connection.

In that case, the two voltage readings will become CLOSER together. But if you put a load on, turn on all the lights, stereo (crank it UP) the heater, etc, this reading will start to go UP because more amperage is now being drawn.
Click to expand...
and if under load, the reading remains the same, that means I have a bunk alternator, correct?
 
67Dart273 said:
Depends on what it reads. I think I got off track.
Click to expand...
okay. this is all hypothetical. say battery x reads 12.3v. now alternator x reads 13.4 with no load on it at all. now, once load is applied to alternator x, volts remains at 13.4 no matter the load
 
alright. problem solved I hope. I started breaking down alot in traffic today. Id stall out and the battery was pretty much dead so it was running like garbage because of extremely weak spark. any time id come to a stop, it'd wanna die and id need to get jumped to start back up. I made it to Advanced and I should probably play the lottery today as they had a squareback in stock for $40 with lifetime. the gentleman who helped me took my battery and said it was pretty much dead and wasn't surprised it wouldnt start the truck. So I took my alternator off with my "oh s**t" kit I keep for roadside emergencies. well. I pulled the old one off and its a roundback :eyeroll:. go figure, but it tested alright so Im just gonna keep it as a spare. so we put the squareback on it and hooked it up. I also had a busted field wire that decided to break at the connector so that got fixed as well. Now I think all I have left is to go back in the morning and hook a ground wire to the alternator case and then to the block using a small piece of 10ga wire and then pop the battery in and see what it does.
 
Now I have this problem.

voltage on batteries 12.3

1--Make absolutely sure the regulator is grounded. Scrape the mount/ flange clean and use star washers.

this is good

2--Work the regulator connector in/ out several times, and visually inspect for corrosion, other damage.

this is good

3--Key on, engine off, use a test lamp or meter to check the blue wire connected to one of the two field wires. Should get a bright light / same as battery voltage.

I do not have any voltage here

4--Remove green field wire at alternator, use a clip lead to ground the disconnected alternator terminal. In dim light you should be able to see a small spark as you connect/ disconnect the wire

it's in the middle of the afternoon I'm outside so I can't verify that I can or cannot see a spark


5--Start the engine, bring up RPM and see if it shows a charge. If it does, you either have
a wiring problem in the regulator circuit, or a bad regulator.

it does not charge

If it does not charge, and if you DID notice a spark at the field, hook a voltmeter to the alternator output stud. With the engine running fast, the voltage should be up around 14, but not really high. If voltage is really high, way over 16--20, etc, you have a bad connection in the alternator main output wire in the path to the battery.

If voltage is low, "same as battery" regardless of RPM, you most likely have a bad alternator.

going to parts store now to get a new alternator


Simplified diagram below:

The "I" terminal of the regulator receives switched 12V ignition voltage, the green wire from the regulator to the alternator controls "the amount of ground" at the alternator field

When you remove the green (F) wire and ground that alternator field terminal, you are causing full field current to flow from the ignition (blue field) through the field magnet, to ground (clip lead in place of green wire)

Dual_Field_Alternator_Wiring.jpg
[/QUOTE]
 
Ok just got back from the parts store in the alternator checked out good.

any thoughts on where to go from here let me know......
 
Im just as clueless as you buddy. Sorry

actually. check the connection of the blue with white tracer wire at the alternator. this might be why you are getting no power at the blue wire. also check the connection at the ignition switch and at the ballast. perhaps you have a bad ignition switch or bad ballast.
 
Figured It out. It Was The Blue And White Tracer Wires. It Was broken And Caused An Open In The Circuit.
 
Well........ not really. i fixed it earlier in the night but you did have the right idea and knew where to look, i just had looked already...... but hey thanks for the thread, it helped me to find it for sure!!!!:cheers:
 
7374 said:
Well........ not really. i fixed it earlier in the night but you did have the right idea and knew where to look, i just had looked already...... but hey thanks for the thread, it helped me to find it for sure!!!!:cheers:
Click to expand...
No prob! Im hoping my problem is solved tomorrow
 
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