At wits end with charging system

[kimcrwbr1]

Get a good motorcraft battery and stop messing around with walmart crap. The high voltage shortly after startup is just the alternator replacing the juice used to crank the motor. I have had bad starters drain the battery by using too much juice for the alternator to replace the juice used especially on short trips. How old is the starter and are all cable connections clean and tight. A bad connection at the starter will create alot of resistance as well as a weak cable. Bend the cables from one end to the other looking for weak spots. Upgrading to larger cable size also helps out in cold weather reducing the amount of resistance in the starting circuit. Maybe just change the start solenoid also as bad contacts will also draw alot of cranking amps out of the battery. It makes the charging system work too hard and promotes premature failure.

 

[Twister]

Well I went to the junk yard and found a windstar with a brand new alt in it, so I snagged the regulator off of it. Hopefully this helps. My battery is toast I think.l, it read 2.88 volts earlier. So I'm am going to have to pick up another. Might go to a local battery shop and pick up a used one. I don't have the money for a new one

Here is a pic comparing the new regulator with the old one. Notice how the new one has nice long and clean contacts.

Sent from, wait how did this get here?

 

[Twister]

After puting the new regulator on, I jumped the truck, it only maxed at 11.5 volts and then dropped fast and the truck died. Is that just because of my battery or is the regulator still bad?

Sent from, wait how did this get here?

 

[RonD]

Yes, bad battery will draw down the voltage, it's the same as a short in the system.

 

[Twister]

Well got alt tested with newer regulator and it test good. So I am going to replace battery. When I do, is there anyway to test for a draw on the battery. Something is killing my batteries and I don't think it is my alt?


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[Twister]

Well got a new battery, installed it and something is making a draw on my system. With it hooked up it will slowly drain. So i changed out the battery cables with different ones from my other truck and changed the terminal connectors. There was an extra negative cable, that i think the previous owner added for the off road lights he added, but i disabled them so i removed the extra ground, it was super cracked and corroded anyway. With all that i think i stopped the draw. But now when i start it, the battery light comes on and the battery only sits at 12.2v . So anyone got any ideas?

I took the battery out and have it inside so it doesn't get damaged by the truck

 

[4x4junkie]

But now when i start it, the battery light comes on and the battery only sits at 12.2v .

Sounds like that "extra negative cable" might've had something to do with your charge circuit, but there's no way to know without doing some testing.

I would check that the ground cable to your engine block is good (probably is if the starter motor is working OK), and that all your frame & body grounds are OK.
Also if you haven't already, check the fuses for your alt in your power dist. box.

If all those check out, then I guess it's time to get out your volt/ohm meter or a continuity tester and start tracing through your wiring for a broken or disconnected wire somewhere.

 

[Twister]

Sounds like that "extra negative cable" might've had something to do with your charge circuit, but there's no way to know without doing some testing.

I would check that the ground cable to your engine block is good (probably is if the starter motor is working OK), and that all your frame & body grounds are OK.
Also if you haven't already, check the fuses for your alt in your power dist. box.

If all those check out, then I guess it's time to get out your volt/ohm meter or a continuity tester and start tracing through your wiring for a broken or disconnected wire somewhere.

Well it did with an without that extra cable. Where I the distribution box, are you talking about the fuse block inside the cab, as that's the only one I have I think.


Sent from, wait how did this get here?

 

[4x4junkie]

Power distribution box should be under the hood (unless '87 is different somehow)

 

[kimcrwbr1]

http://www.therangerstation.com/tech_library/chargingsystem.htm Read this all the way through and follow it step for step. Fully charge the battery and let it sit overnight and see if it looses juice. It is real important that all three are in good condition alternator, regulator and battery. Until you can get it to pass the no/load and the load tests do not run it very long any one bad component can destroy the other two in short order. The first step is go through the wiring completely. Once your sure the wiring is good you can then diagnose the charging system. Read through the link I gave you a few times and plan your attack. Also did you clean the armature contacts I take a fine flat file and spin the armature to dress up the contacts then use a small screwdriver to clean the grooves in between the contact and clean it good with electrical cleaner and air pressure. GL and dont get in a hurry. This is for the 1987 correct?

 

[Twister]

http://www.therangerstation.com/tech_library/chargingsystem.htm Read this all the way through and follow it step for step. Fully charge the battery and let it sit overnight and see if it looses juice. It is real important that all three are in good condition alternator, regulator and battery. Until you can get it to pass the no/load and the load tests do not run it very long any one bad component can destroy the other two in short order. The first step is go through the wiring completely. Once your sure the wiring is good you can then diagnose the charging system. Read through the link I gave you a few times and plan your attack. Also did you clean the armature contacts I take a fine flat file and spin the armature to dress up the contacts then use a small screwdriver to clean the grooves in between the contact and clean it good with electrical cleaner and air pressure. GL and dont get in a hurry. This is for the 1987 correct?

Thanks, ill read that over. Yes this is on an 87 with a 94 Taurus 130amp 3g alt swapped in.

 

[kimcrwbr1]

It wouldnt hurt to upgrade to larger cables and have you added a ground wire from the alternator body to battery neg and clean the ground from engine to chassis usually between the head and the firewall.

 

[Twister]

It wouldnt hurt to upgrade to larger cables and have you added a ground wire from the alternator body to battery neg and clean the ground from engine to chassis usually between the head and the firewall.

Already cleaned them and added the wire from the alt case to the battery.

 

[Twister]

Power distribution box should be under the hood (unless '87 is different somehow)

Unless the previous owner worked some voodoo magic on the truck, or i am blind, there is not one under the hood. Would you mind snagging a pic of where yours is?

http://www.therangerstation.com/tech_library/chargingsystem.htm Read this all the way through and follow it step for step. Fully charge the battery and let it sit overnight and see if it looses juice. It is real important that all three are in good condition alternator, regulator and battery. Until you can get it to pass the no/load and the load tests do not run it very long any one bad component can destroy the other two in short order. The first step is go through the wiring completely. Once your sure the wiring is good you can then diagnose the charging system. Read through the link I gave you a few times and plan your attack. Also did you clean the armature contacts I take a fine flat file and spin the armature to dress up the contacts then use a small screwdriver to clean the grooves in between the contact and clean it good with electrical cleaner and air pressure. GL and dont get in a hurry. This is for the 1987 correct?

Read that over. Did the test for a drain on the system, by hooking a test light to the disconnected negative battery cable and the negative terminal using a test light i made from turn signal connector. With it hooked up, the light comes on. According to the tech article you linked to i should have a short somewhere in the electrical . I pulled all the fuses and it didn't go out . I am thinking about ripping out the alarm system i put in the truck to see if that is what is causing it. I ran out of light today so i will have to mess with it more tomorrow.

 

[kimcrwbr1]

There may be a couple things that give you a false or indirect short like the computer and radio memory. Your on the right track start disconnecting components and isolate the fault. Electricity flows from negative to posative but you want to troubleshoot from posative to ground.