Having problems with the unforgiving charging system in my 66' Malibu. Everything from the coil to the battery is brand new. Basically everything electrical is brand new. Start the car with first alternator, everythings fine but gen light is on, run it a round for a while light does'nt go off with lights and everything on. Put the the multi meter on the battery,shows 9.4 volts same on the lead wire on alternator, horn relay same thing. Red wire on voltage regulator same thing. This all with engine running above idle. Promptly remove alternator gave it back to Auto Zone tell them to give me another one. Put it on seems to put out around 13.8 volts. But still have the gen light on. Measured blue wire reads 6.5 volts, white wire 2.3 volts same at regulator.Quit for the night checked it again the next day,after jumping the battery and again reading around 9.something volts. What the hell? The brand new borg warner select regulator is grounded properly. belt is tight,battery has been tested and is just fine. Can't really run it around town yet,not legal. Have to jump it everytime to start it. Unless I take the battery to O'reilly's to get it charged, I have to jump it to start it if I have been running it for testing. Is the remanufactured duralast alternator from Auto Zone just a lump of crap or what? Or is something killing it. Should I take it to pro or what?
Cheap Alternator?????
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With the alternator connector plugged in, engine running:
Use a probe and a jumper wire. Jumper alternator blue wire to alternator B+ (red) wire. Jumper for a couple of seconds. Measure the blue wire afterwards. See if it stays near 12 volts and the light goes off. If it does you need to get the battery recharged again. The alternator won't do it.
Use a probe and a jumper wire. Jumper alternator blue wire to alternator B+ (red) wire. Jumper for a couple of seconds. Measure the blue wire afterwards. See if it stays near 12 volts and the light goes off. If it does you need to get the battery recharged again. The alternator won't do it.
Jumped blue wire to red wire, light still on getting even lower voltage almost nothing. Like .01 volts on white wire and nothing blue.This is very odd. Pull the ground off voltage regultator,voltage at blue wire is 5.4 volts and white wire is a little higher at 6.4 volts. What the hell is going on here? Should'nt blue wire output be bigger than white wire? Alternator output is dropping with ground wire connected, disconnected output is 13.8 and steady. Is it possible that this regulator should'nt be grounded? Can it be grounding through the harness somewhere? It rides on the rubber bushings in the radiator support so I know it's not grounding to it. Does it need to be adjusted or what? I just don't get it.
Try testing things Bill's way. The output of the alternator should go high because the regulator is not in the circuit. Yes, regulators need to be grounded. See below.
charbilly2001
Team Member
From: Temecula, Ca
Registered: Oct 2001
posted 08-11-2002 10:19 AM
---------------------------------------------
Remove the plug from the regulator and jumper the plug from F to 3( not the regulator...the plug.) Start the car and measure voltage across the battery at around 2000RPM. What you have done at this point is to give the alternator full field current. If the alternator does not give you maximum output then it is bad. If it does work properly then your regulator is bad or you have some other wiring problem.
This test is solely intended to prove the alternator is working properly. Post the results please and we will go from there.
charbilly2001
Team Member
From: Temecula, Ca
Registered: Oct 2001
posted 08-11-2002 10:19 AM
---------------------------------------------
Remove the plug from the regulator and jumper the plug from F to 3( not the regulator...the plug.) Start the car and measure voltage across the battery at around 2000RPM. What you have done at this point is to give the alternator full field current. If the alternator does not give you maximum output then it is bad. If it does work properly then your regulator is bad or you have some other wiring problem.
This test is solely intended to prove the alternator is working properly. Post the results please and we will go from there.
Okay I'll try that later tonight. Gotta get this car on the road. Its like a part of me is stuck in the damn garage going nowhere. Thinking of taking a vacation just to get her up and going. Can't sleep at night, need my chevelle.
Alright, I flashed the new alternator, small spark, measured voltage and everything is exactly where it's supposed to be. But still have the gen light on. Not sure why, alt b+wire is 13.8 and above when idle increased,and field wires are where they are supposed to be. Blue at battery voltage around 13 to 14+ white wire is 7.6-8 volts. Is the gen light on because the battery is not fully charged. When I leave the multi meter on the battery both cables connected, it is slowly discharging. What is making this happen? If I do a parasitic discharge test with the positive cable connected and the negative cable disconnected and touch the negative terminal to the negative cable there is absolutley nothing draining it. Getting closer but not quite perfect yet. You guy's are doing a helluva job, flashing the alternator is a great concept. By the way changed from borg warner select regulator to a a wells vr715 soild state. Seems to be doing the job. Just don't know why the gen light is still on.
"parasitic discharge test" Somebobody that speaks the lingo.
The light will stay on as long as there's a voltage differential across the bulb. The alternator blue wire ties to the alternator brown wire through the regulator. When field voltage comes up this needs to be near battery voltage (>12 volts).
The other side of the lamp gets power from the pink wire off the ignition switch. In a running condition this is also battery voltage. When the 2 sides are near equal the lamp goes off. One side is low, either the brown wire or the pink wire. Most cases it is the brown wire from the regulator.
The light will stay on as long as there's a voltage differential across the bulb. The alternator blue wire ties to the alternator brown wire through the regulator. When field voltage comes up this needs to be near battery voltage (>12 volts).
The other side of the lamp gets power from the pink wire off the ignition switch. In a running condition this is also battery voltage. When the 2 sides are near equal the lamp goes off. One side is low, either the brown wire or the pink wire. Most cases it is the brown wire from the regulator.
Should I have the battery rechecked for problems because its not maintaining the charge the aternator is giving it with both cables connected. Is that why the light is still on? Also the light seems a bit brighter than it used to be.
With the car not running:
Disconnect the alternator plug.
Turn the key to ON.
Measure the blue wire to ground.
The voltage should be near battery (+) voltage. What you are reading is the voltage from the ignition switch and through the idiot lamp filament.
Turn key off.
Install the alternator plug and start the car.
Again measure the blue wire to ground.
You should have a postive voltage around the same value as the alternator output.
If so, the lamp should be out. When voltage is equal on both sides of the lamp, the lamp goes out.
Disconnect the alternator plug.
Turn the key to ON.
Measure the blue wire to ground.
The voltage should be near battery (+) voltage. What you are reading is the voltage from the ignition switch and through the idiot lamp filament.
Turn key off.
Install the alternator plug and start the car.
Again measure the blue wire to ground.
You should have a postive voltage around the same value as the alternator output.
If so, the lamp should be out. When voltage is equal on both sides of the lamp, the lamp goes out.
Okay narrowed it all down to the voltage regulator. With it plugged in voltage dropping rather quickly, unplug it and voltage climbs right back up to where it was and maintains this 12.50 volts on battery. It's the wells solid state regulator.It also seems to be overcharging, at 15 to almost 16.3 so I am going to ****can it. Try the borg warner adjustable one and it won't even attempt to work. Tried moving the contacts to different gaps and nothing. Alternator starts at 13 volts and is slowly dropping. Should I spend around 50 bucks and pop for the Delco Regulator or think about the ex to internal regulated alternator swap, because this is making me very gray headed.
Before I'd toss the Wells, see if you can get a replacement. AutoZone here warrants the item. Diconnect the battery before installing and ground the Wells case.
BTw
I prefer my gray hair over no hair.
BTw
I prefer my gray hair over no hair.
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