Wiring alternator regulator

bucholzi

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Well, the bugs keep on surfacing... The charge is gone. -cuss

First I need to check the wiring to the alternator regulator: I installed a new one 3 years ago (however, the truck has only been driven a couple of times since :rolleyes: and this became apparent when I installed a voltmeter) and I need to eliminate that I didn't mess up installation, as the colors on the wires did not match and the old one did not have letters on the terminals. This one has, so it should be easy to check. And since I can't find a wiring diagram which can help me, I need to ask you guys :hail

I assume I is for Ignition, which should be the green wire (which also is the only wire not coming from the alternator).

A should be Alternator, and is connected to a yellow/white wire which again is spliced to a fat black/orange wire coming from the bolt connector on the alternator. Reckon that is ok.

But then there is F and S, which I reckon is Field and Stator. There is one white/black wire and one orange/blue wire, which both comes from the same connector-plug on the alternator. So the question for now is: Which wire is stator and which is field? :confused:
 

87crewdually

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Block C-3 on the below schematic. Just read the colors and match them up to the letters: S I, A, F, ect.

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bucholzi

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Excellent diagram ;Sweet

Wiring was correct, and testing according to this made me :confused:. The harness had power on ignition wire when ignition was one (with appearantly 0.2 volts power loss compared to battery) but when the harness was connected to the regulator it dropped to about 1.6 volts on the terminal??

Also the field wire only had 1.5 volts with ignition on and also when engine running, and it should read between 3 and 12 volts. However, suddenly it gave 6-7 volts, after i jumped the field and alternator/power wire to check for magnetism.. And when I started the engine again the ******* had charge. I also gave the alternator a couple of clanks with a hammer, right before I started but after the regulator decided to behave, so I can't say for sure what made the difference :rolleyes:. Apparently I need to carry a piece of wire, a hammer and a voltmeter until I sort out what the real problem is.
 

Agnem

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External regulator alternators are the easiest to troubleshoot. The concept is simple. Supply 12 volts to the field wire, and you will generate the maxium voltage and current your alternator can put out. The regulator has I think 4 wires going to it. It looks like this when viewed from the front of the truck...


========================
--- 1 ----------------2---3---4

Terminal 4 I believe is the field or F. 2 is the I or Key-On 12 volts. All you should have to do to test your alternator, is disconnect the plug, and on the harness short pins 2 and 4 together with a jumper wire. This will full-field the alternator, and it should make juice like crazy. If it does, your problem is the regulator. If it doesn't, then the alt is bad. Don't forget to make sure your alternator is cold when shut down. Bad diodes in an alternator will cause it to draw current, get warm, and kill your batteries.
 

icanfixall

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Years ago I had a charging problem with my alternater. Turns out the wire that shows the dash gauge meter was broken but... It was broken after the connection at the alternater. The plastic wire crimp was fine but the wire connection to the wire connector was broken. I found this a nite and only because I saw some arcing at the broken connecter in the dark. Fixed it and the dash aguge worked again. Actually I always was getting a charge. It was the dash gauge that wasn't showing a charge happening.... Sure did chase that problem for a long time...... I have no idea why that connecter was broken either. You really had to look closely at the wire to see the copper wires were broken but the plastic crimp was fine to the wire lug...:eek::D
 

Agnem

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Along those lines, the 92 and up trucks rely on the dash cluster to feed the alternator charging circuit. If for some reason, you were to pull your dash cluster out, your battery would cease to charge. Just an FYI, in case anybody ever needed to do that for some reason.
 

bucholzi

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Well, after running a few minutes with around 13.5 v charge suddenly it took of, and reached 17 volts after a few seconds. Reckon the regulator is toast, it smells somewhat burned :puke: Well, at least the alternator puts out some juice at least.
 

bucholzi

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External regulator alternators are the easiest to troubleshoot. The concept is simple. Supply 12 volts to the field wire, and you will generate the maxium voltage and current your alternator can put out. The regulator has I think 4 wires going to it. It looks like this when viewed from the front of the truck...


========================
--- 1 ----------------2---3---4

Terminal 4 I believe is the field or F. 2 is the I or Key-On 12 volts. All you should have to do to test your alternator, is disconnect the plug, and on the harness short pins 2 and 4 together with a jumper wire. This will full-field the alternator, and it should make juice like crazy. If it does, your problem is the regulator. If it doesn't, then the alt is bad. Don't forget to make sure your alternator is cold when shut down. Bad diodes in an alternator will cause it to draw current, get warm, and kill your batteries.

Mine actually is F - S - A -- I when viewed from the front of the truck (I closes to the engine)
 
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icanfixall

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I was having regulater issues years ago come to think of it. A family owned mom amd pop starter and alternater repair shop told me to disconnect the batteries before I plugged in my regulater. This was after I had burned up two I had bought from them.... So I did and never had any burn out issues again. I have no idea why these regulaters were going bad just because the power was on and ready to hot them up but... If it works just do it...:sly
 

Agnem

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Mine actually is F - S - A -- I when viewed from the front of the truck (I closes to the engine)

OK, I stand corrected. All I can remember is which ones you short together to full field it, and to the best of my knowledge that doesn't change.
 

bucholzi

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I need to make some calls tomorrow, but I would be surprised if anyone in town has a regulator in stock, can I use any 12 volt external regulators if I can find one in the scrapyard?
 

87crewdually

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This might be a good time to do the 3G alternator conversion. For $30 I got a rebuilt alternator (I took it apart and all is new) in the junkyard off of
a 97ish Ford Taurus V6. I also grabbed the heavy gauge charge wire and the big 175amp fuse. Super easy install with just a couple modifications. The benefits are it's smaller, puts out 130amp instead of 60, less wires, no more voltage regulator, and a steady 14+ volts all the time.
 

bucholzi

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This might be a good time to do the 3G alternator conversion. For $30 I got a rebuilt alternator (I took it apart and all is new) in the junkyard off of
a 97ish Ford Taurus V6. I also grabbed the heavy gauge charge wire and the big 175amp fuse. Super easy install with just a couple modifications. The benefits are it's smaller, puts out 130amp instead of 60, less wires, no more voltage regulator, and a steady 14+ volts all the time.

Been thinking about it, but I reckon it would be a ***** to find the correct alternator at the scrapper as US cars don't grow on threes around here, so unless I can find a suitable alternator on a european or asian car I need to buy a new or re-manufactured one. And I have thrown enough money at this truck by now. To make sure my batteries are well charged I might install a DEFA maintenance charger, which is way cheaper than a new 3g alternator, since the winters here are long and cold, and the truck is usually always hooked up to the engine heater anyway.
 

Agnem

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Pretty much any earlier Ford with the 1G alternator will work. If the connector fits, wear it. LOL
 
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