alternator wont charge...is there a special "break-in" procedure

i cant seem to get my alternator to charge properly. Is there a special way that i need to excite my voltage regulator so that it works. Ive tried raising the car in RPM so that it will kick the alternator into gear but alas nothing. My volt gauge reads 8-9 volts while the car is running and 13 when the car is off. i hooked my gauge wire off of my coil because i figured that would be a constant 12v's while the key is on (i hope that is alright)...but now im stuck, any ideas? i cant take the alternator to get tested because all the stores are closed so im just trying to think of things i can do while i wait
bob

oh its a ford motocraft with an external regulator

<!-- / message -->

 

The coil probably has a ballast resistor hooked to it and that's why you're only reading 8-9v... Check it across the battery terminals or on the batt terminal on the back of the alternator with a dvm if you have one. Even if it wasn't charging, while running you would still get a reading close to the battery voltage when the car is off, not way lower.

 

we pulled the negative off of the battery and the car quit running, could that be because i have the alternator hooked to the negative off of the battery and not grounded to the car?

 

it sounds like you got a wire backwards or in the wrong spot. had the same problem in my truck. if i can remember rite, long time ago i did this, it was one wire to the batt. side of the ignition switch an the other to the acc. side of the switch. i forget witch wire went where.

 

Huh? You mean you have the ground terminal of the alternator hooked to the battery ground? Probably not the easiest way to do it, but it shouldn't matter. Ground is ground.

 

what alternator do you have? internal regulated? external regulated? one wire? 3 wire? how exactly do you have it wired?

 

actually it was the easiest way to do it lol, the ground wire off of the battery had a splice in it for a connector so i went off of that. The more i think about it tho, that wouldnt it kill the ground when i pulled the neg. battery terminal off of the post since it is all connected?

 

motocraft, externally regulated via a voltage regulator...i matched up everything on the back of the alternator to the regulator (stat. - S, fld-F, etc..)

 

Try hooking your gauge to something you know is gonna be alternator/battery voltage like the positive battery terminal. When you say you're reading 13v with the car off, what position is the key in, acc, run or completely off?

 

Details !I've got tons of manuals to 1936.....mechanical regulator or transistor???? What app. / year is the alternator or generator. You have to polarize in a certain procedure...your answer is in the Details !

 

key is in the acc. position

 

Have you checked your field voltage? It should be half of your charging voltage. You can feed it battery voltage (full field it) and see what the alternator is putting out. Alternator output lead should go to the positive battery terminal or your kill switch if you have one.

Flatman

 

Generally, you shouldn't have any voltage to the coil in the acc position, it's purpose is to run the accessories without powering up the ignition.

 

make sure that the regulator is grounded too.

how may terminals does the regulator have? three or four? field , stat , battery.....and is there an I for ignition? if so , i think that needs 12 volt power when the ignition is on


worst case , it could take the alternator off and have it checked

 

wait im retarded and didn't go look before i typed...voltage is at the coil when its in the "run" position (one click down from the "off" postion and not one click up)

 

If you have free long distance...pm me and I'll go over the procedure. I'm not typing a manual to cover the variables.

 

4 terminals, i was wondering what the "I" was for. I was figuring indicator lamp...but that would complete the cycle if it went to the ignition. So i should have a wire running from the regulator to the ignition now? and if so what position on the ignition?

 

yes , you could put an idiot light in that circuit , but i don't think you need to. i'm not 100% familiar with motorcraft

just 12 volts power when the ignition is in the running position..why don't you try just a temporary jumper wire to the " I " while the motor is running to see if it starts charging. you could jump it from the batt terminal

if you get sparks , stop

1959cac , you seem to know more about this.....your input is welcome

 

I'm not familiar with Fords but I'll throw a couple of things out here.

1. NEVER pull a battery cable off to test alternator output. This can cause the diodes in the alternator to fail.

2. You don't polarize any alternator systems. Generators are polarized, not alternators (they are alternating current till the power goes through the rectifier) That's where the name comes from.

3. Just get a wiring diagram for say, what ever car you bought the alternator and regulator for and wire it up. Here's a sample

http://www.explorerforum.com/photop...M_Ford_charging_starting_wiring_diagrams_.jpg

 

On the other hand it could just be a bad alternator. I put a new one in my Plymouth last yr, drove it a couple of times before winter did not pay much attention to it then, This spring it was not charging at all, took it back to NAPA they checked it and sure enough it was bad, replaced it for free

 

THE "I" terminal does go to the indicator light (or a volt gauge) and the system needs this to energize, as I remember on those Ford alternators

 

that's what i was thinking , but not 100% sure....it's been a while since i messed with one of those

 

so run a wire from the + of the volt gauge to the "I" terminal then

 

If non original, a one wire alterantor is so much simpler. Put one on my Hot Rod with a set of deep groove pulleys, 9000 RPM REVS do not throw the belt.

 

so what happened when you ran a wire to the " I " terminal on the voltage regulator? did it start charging?

 

trying to keep costs down on this one and one-wires, although nice and easy, are costly. Oh and im running a serpentine belt

 

it sparked when i ran 12 volts to it but i couldnt tell if it charged or not...would be nice to have another set of hands but no one is home lol

 

Settle down , It is simple .
first unplug the reguator and hold the plug in you hand. find the field wire in the four tern minal.. (Hint may be marked F) Find the power terminal . use a test light and see which one has 12 volts on it or power all the time. Jump the power wire to the field and start the engine . using a voltmeter connected to the BATTERY see if battery voltage risies with engine around 1500 RPM . Dont run it any longer than necessary. If the voltage is rising when using the jumper wire then the alternator is fine (using the jumper wire byp***es the regulator and ful fields the alternator so it will either charge or it wont. if it charges the alt is fine andthe reg is a bummer , change it. If it doesnt charge the Alternator is bad. (probably just brushes in 90% of cases.) If someone has a 70s Motor manual handy in the rear section under Generla service there is an alternator section. Under motorcraft you will find this test with a diagrapham which will be a big help of you are hesitant to do this. Test should take less than ten minutes tops. it is the definative charging sytem check and works oin all makes. Once you learn it you will NEVER need to have an alternator tested again. you can do it in 5 to 10 minutes yourself. BTW Alternators are not polarized , Generators are. Also on the page in the motors manual will be a very good wiring diagram for this system in understandable form. Alternators are easy to diagnos, easier than generatirs sytems in mist cases. They are so simple it throws us because we keep thinking, "I must be mssng something it cant be that simple" but it is. Maybe we should have done a tech week theread onesting all alternator systems popular from the big three. Then everyone would have it and never be stumped again. They all test the same way and it is very easy to do.
Don

 

wow thanks for the info...gonna def. try that tomorrow

 

Is there a horn relay in the system? Some charging systems used the horn relay. Also pulling the cable while the engine is running can fry your voltage regulator. What type of car is it? Some old fords have fuseable links instead of fuse blocks, ove rthe years when the burn out, some people will just replace them with wire. Have had the wire be in the middle of a bundle burn through, and you can't see it. I'd check continuety on all wires. I have also gotten bad alt. from the part store, pull it and have it rechecked.