Help please,
My battery will not hold charge...

1. checked the alternator, holding charge.
2. remove and replaced the regulator (cheap)
3. charged the battery..seems to be ok for a day or so then dead again.

Is it true when you start the car and let it run: to check if the alternator and regulator works, disconnect the battery and see if the car is still running...my 1200 stops running. why does this happen after I verified that the alternator is holding voltage (13+ volts) and the regulator is new plus the battery is recharged.

first, alternators are NOT like generators, the produce alternating current that must br rectified to direct current to be capable of charging a battery.
second, an alternator wil not normally keep a vehicle running with a battery disconected.
third, disconecting a battery from an alternator type charging system will send a voltage spike through the electrical system that can and usually will cause damage. most likely affected will be burned diodes in the alternator.
NEVER under any circumstances disconcet the battery with the car running unless you like to take the chance of having to spend lots of money repairing the damage you can cause.
this is based upon my over 25 years of repairing cars for a living.
as a best guess, first your battery was extreamly weak and needs to be replaced.
IF you are lucky, you haven't done anyother damage to the system. but to be on the safe side, check the alternator and the regulator (yes I know you just replaced it, but check it any way) and for good measure, check that the fuse in the fuse box is still good and the fuseable link at the battery. (there is a charging system fuse)

I just replaced mine yesterday, similar problem.

How did you check if the alternator was actually charging? with a voltmeter? You can also check by turning the lights on, and if it's working properly, they should glow brighter.

I didnt know that you were supposed to take the battery cables off, like rgrinder said, but that also is a way to test. Taking the cables off the battery with the car running, should not make it stall, it should continue to run, with an alternator with and internal or external regualtor.

My guess is the connections. If you are positive the alternator works, then it's the wiring that connects to the back of the alternator. My new alternator, for some odd reason, will not charge, unless i have a connecting wire going from the postive termial on the alternator, to the 'field (F)' connector on the alternator. But then again, i have an internal regulated alternator from a 120y.

compare to the connections to another one, thats how i fixed mine...or just take it to an auto electrician.

-Jesse

The voltmeter test is: 13.5 - 14.5 volts, engine running, headlights on. If it is under 13.5 volts, try revving the engine to 1500 rpm. If it is over 14.5 volts, replace the regulator.

The battery going dead overnight could be caused by something stuck "on", like a miswired stereo, a light switch that doesn't go off, or a bad diode in the alternator.

You guys are gods....will trouble-shoot once again with your comments...

did a voltage check when car is running and voltage reads good on battery.. but when I shut off the car then checked the battery for voltage, the voltage drop gradualy no F@#ng clue why...all lights, electric fan (no radio) are turned off..I guess I have a short some where or a bad diode..

correct me if I'm wrong but this could be
1. battery cannot hold charge anymore
2. something grounded
3. a diode bad in my alternator

I do appreciate all you guy's help!!
Cel

Place a AMMETER in series (inline), when the engine is turned off. This will show the off-position current draw. It should be in the region of 10's of milliamps as opposed to 100's.
Lift the Negative off the battery, and place the ammeter inline. With the engine off. Otherwise you may draw more than 10A of current and blow up your ammeter.

The voltage test is a good first look, and as you say, it appears that the electricals are drawing current when the engine is not connected.

Chris

I think your battery is dead. Plain and simple.
How old is it? How many times have you discharged the battery(left the lights on) in the past?
Change you battery and clean you battery terminals.

They were right when they say to do a
draw test on the electrical system.on the
1200 you can put a test light inline with
the negative cable and the post. it should
either not light up or be very dim..
this test doesn't work on modern cars
but does on older cars. once it lights up
you can pull out one fuse at a time till
you isolate the circut.. then you have a place to start..
I am also in San Diego
email me at wubbitsville@cox.net
I am a Lexus (12 years) and Nissan
(8 years) Technician . If you get stuck
I would be happy to look at it plus it
would be nice to see another datto.
good luck Wubbits