alternator not putting any power out ??

[monty1704]

hi there once again lol i am still having no charge out of my alternator im wondering if i have missed anything ?? naw i dont have a charge light as i have read in a previous post do i need one ?

were can i get a wiring diagram to see how everything goes and if i have made a mistake or anything like

thanks dave

[AlleyNiki]

Hold on, in your previous post about this you reckoned your ignition light wouldn't go out. Now you're saying you don't have one?

I've just been having problems with my alternator and I sourced the issue to the regulator. But my charge light stopped coming on altogether!   

I have a circuit diagram but it's only a wiring block diagram. But yes, it shows that a wire goes straight from the battery to the starter motor, then to B+ on the alternator.

Also, is your car an aircooled 126p, or a 126BIS (things may be entirely different on a BIS, as I have an aircooled)

Alley

[monty1704]

hi thanks for the reply right before i go any further i do not have an original wiring loom i have had to build 1 due to it being a blitz buggy with all the fiat 126 running gear but the person i had it off stripped it all out and lost everything, so i have made my own.

 its all fused and earthed the ignition light does not go off because it is a warning light i wired up to check i had ignition power.

i put an alternator tester and there is no power from alternator at all ?? and on top of the alternator i have a little round cyclinder looks like a condenser with a black wire on it that is going to the B+ terminal aswell as the power wire from battery ? is this meant to be there ?? and i am not sure weather my engine is a 126 p or a 126 bis i no it is 1979 model tho any advice would be great thanks

and it is an air cooled model

[AlleyNiki]

If it's aircooled and you don't need to fill it with water, then you have the standard 126, and not the 126BIS. BIS is liquid cooled.

If you haven't already, watch this:
[youtube]http://www.youtube.com/watch?v=EqdrkZu50Vw[/youtube]

so you know how an alternator works.

Now you need to figure out if the fault is in the rotor coil (electromagnet), field windings, brushes or regulator.

I really can't know exactly what wiring you have on the alternator, (you might have a different one to me)
but basically mine is as follows:

*Large output wire coming out of B+, which goes to starter motor then to battery.
*Smaller wire (black) alongside the larger output with a spade type terminal which always carries 12v. Goes to lower cluster of contacts on alternator which goes to one of the brushes. Comes from the instrument panel's charge light. I assume (but don't know for sure) that this powers the regulator and  electromagnet. Someone correct me if I'm wrong.
*Another wire (brown) similar to this one which seems to come from the alternator's diode rectifier. Also goes to the group of 3 contacts.
*Another wire (yellow) which goes on this contact group and comes from the regulator. I assume this wire 'tells' the regulator what voltage is being produced at the rectifier and whether it should excite the electromagnet more or less. Again, this may be incorrect, but it seems to make sense to me!
*A single thicker green wire coming from the regulator and going to the top contact on the alternator. Completes the circuit for the rotor / electromagnet.

Like I said, you may have a different alternator. Try taking a photo of it and putting it up?

And what I did to test mine was this: (And If you have no idea what you are doing, then you may want to take it to a mechanic to test for you.)
 Disconnect all wires from alternator. And carefully put the wires with 12v aside so they don't arc on the metal engine body! Then, take 12v straight from the battery, or another supply, through some crocodile clips. Start the engine up and while the alternator spins put the 12v across the two brush contacts, and with the multimeter test what voltage there is on B+. Mine read 15 - 19 volts. Be careful though, because there is that fan belt right in front so don't get your fingers caught. I also held one clip and put it on the contact very quickly and took it off, as I'm certain full 12volts is not good for the rotor. (I got a bit of arcing)

As I got 19 volts from B+ when putting the 12v across the brushes, I know the windings, rectifier and rotor are fine. The regulator is at fault!


I have to stress that you should really do this with the alternator out of the car, by spinning it up with a drill. I got pretty close to that belt as it was spinning..

Also, test the brush contacts that there is an electrical path flowing between them with the multimeter. I took mine out and cleaned 'em.

Phew, hope some of that helps.

Alastair

[monty1704]

well i bet you have got numb fingures after all that lol rite i will take a picture 2moro naw and post and run test as u have shown yer i am good with mechanical work and small electrical jobs as long as i have and idea were im going thanks for all you help and info i will post pics 2moro and run tests and let u no exactly what my findings are many thanks again

[AlleyNiki]

No problems , we will really be able to tell when you put the picture up.

Alastair

[monty1704]

hi i have tryed to put a pick up but it says the file is to large so i will keep tryin if not could i mail u it ??

[AlleyNiki]

Sure, you can email me, it should be on the link to the left there.

I'm a bit busy currently but should be able to look at it in a day or so.

[AlleyNiki]

Hi Monty,

I got your email and sorry it took so long but I've had a nasty past fortnight.

Anyhow, the alternator you've got looks a bit different to mine, especially with that capacitor whatsit on the outside, I think normally they are kept inside next to the rectifier.

The closeup shot you took shows smaller wires going onto the alternator down on the right. I can't see down into the lower right past the alternator, but if it's anything like mine there will be a regulator down there coming off two of those wires. I've known 126's to have their regulators mounted on the side in the engine bay as well (looks like a black rectangular box, sometimes.) Mine is a metal, grey box on the right and down mounted onto the alternator.

Anyway I suggest you take the alternator off entirely and spin it up without the regulator on. might indicate something!

Ciao,

Alley

[monty1704]

hiya yer ain stoped myself lol yer that what i was curious what was the lil round thing with the black wire on it i think next stop for me is an auto spark see what he says.

and yes the wires on the side do go to the regulator which is a little silver box, a nite mare this is being lol ill pay 4 it 2 b done the it be sorted lol but thank you for all your help was much appreciated.. hope to hear from you soon dave

[dajwid]

This may be a silly question, did you check the bulb on the dash?

[AlleyNiki]

This may be a silly question, did you check the bulb on the dash?

I'm a bit confused about his ignition light situation, but he mentioned that it was wired differently so that it would never go out and just show that he had power to the car..

[AlleyNiki]

Oh, and in case people were wondering-

I GOT A NEW REGULATOR AND NOW IT ALL WORKS PROPERLY YAAAAY!