Outer Limits 4x4 Board

Stoopid alternator.
having problems all the time with electrical issues.
After putting in a second hand unknown quality mistu alternator it used to charge at 13.4 volts, this was all good until i arked my battery out on my bonnet and not having a good enough earth to body and frying my accel cable.
alternator doenst seem to charge at this point, going at around 8volts crap.
put proper earth back on, still crap.
drive home 150km using bonnet release as handthrottle(another story)
get home kick the car , come out a day later, alternator now charging at 14 volts. better then ever.
thought problem was fixed.
flip to yesterday, battery flat, alt dead, 8 volts again, bugga.
go to take it out to change it over today for another alternator i thought might fit, but doesnt so i end up putting my old one back in.
Now charging at 12.5 volts, (but after charging my battery on battery charger)

does anyone have any ideas?

also note
i have only got the charge wire hooked up to the back of the alt, sparky mate said that i only needed this, didnt matter if i didnt have the charge light wires. This alternator is internal reg aswell.

Sounds like you shorted out the regulator on the other alternator.

Why did the battery short on the bonnet??? Wrong size/height battery?

Years ago when i fitted a larger alternator to an older car, i needed that charge light connected to my dashboard with a little lamp to indicate if there was a problem with charging. So i'm thinking its required to make the regulator work correctly, and its pretty simple to do. Also helps you to know if there isn't any charge as the warning light comes on.

I used to have a 40 that had same sort of problem. Battery just one day stopped charging, then charged again the next, and one day stopped all together. tried alternators, regulators, the lot. COuldnt figure it out. Then realised that the charge light was part of the circuit, and since one wire had come off it behind the dash it wasnt charging. Soldered it back on good as gold. Remember this was a forty though, been around along time before jesus was playing fullback for jerusalum. Maybe you need your charge light to form a circuit?

i should be able to work out which is the charge light, just need to figure out which one is connects to.

the letters on the back, should this tell me where to put it. anyone know what they are. i think they are something like B+ or something.

Some cars rely on the charge light to excite the alternator circuit - this is the setup where the charge light goes on when you first start the car and stays on for a few seconds, then goes off.

I'm not sure whether this applies to Sierras but it's pretty common.

Either way, I am not clear from your description of events whether you are still using the battery that you shorted out or not. If so, that could at least explain why it was dead the morning after it had been charging at 14ish volts. If you are still using a battery that you shorted really badly, you might need to consider getting a new battery, or at least trying a borrowed battery to see if you can isolate the problem.

Final point - these alternators are really cheap second hand.

Jason

lashed out a got myself a 95 courier alternator and it is good for 60amps, fits perfect too:P

now there are two connections on it, anyone know what should be connected?