Ok my friends......I am officially frustrated. I went back to the car....jump started the battery, and like before, the engine started without hesitation. Since the last time the battery didn't charge enough to start the engine again, I started the engine and kept it at about 1500rpm's so the alternator spins faster. I disconnected the jumper cables without any changes on the engine's behavior, but a couple of minutes later, the engine just stopped! When I tried to start it again, turning the key didn't do ANYTHING....the engine juice was still MIA.
Someone suggested that maybe the problem is the voltage regulator....but what could have had drained the 2-month old battery from one day to the next? I didn't leave any lights on, the key was not left in the ignition, and I rechecked (and found nothing out of the ordinary)all the grounds!
Maybe you have a short or draw somewhere. You can check for a large draw with a voltmeter but anything into the milivolt range can best be detected with an inexpensive tester. Go to your local parts store and buy a pigtail and socket for a side marker. (any type will work so long as its for a small bulb-I prefer 1194 bulbs.) Attach a alligator clip to each lead and install it between the negative battery post and the negative battery cable. (positive connected, negative disconnected from the battery.) If it lights up, you have a draw or short. ( make sure ignition is off, lights off, door closed, etc...) to find where it is simply start pulling fuses until the light goes out and trace out that circuit. Since most systems are fused this works 95% of the time. It also sound like your alternator or voltage regulator is not working. Take the alt off and have it tested and make sure they do a diode check since an alt test will show it charging but if the diodes are bad it is just "charging itself"-think of a diode as an electrical check valve- it should only flow one way. Another possibility is a bad battery. It doesn't happen often but even new batterys can develop a bad cell which essentially shorts out the battery. That should be enough to keep you busy for a while! Hopefully checking these out will solve your problem.
I had a similar problem when installing a new alternator with an internal regulator, turned out it had a faulty unit and it was not charging. I replaced the alternator and had no other issues. On another car my old voltage regulator actually cooked my battery and caused it to boil.
Thank you for your input! I will do "trial-and-error", with the test you explained. I think I will start by taking the battery to get tested under the warranty, and then go from there.....and hopefully I'll get to the bottom of this sooner than later.
Make sure you do not see a spark (or use the bulb check) when you connect the new battery (with everything off). If you have a draw, it will just kill the new battery...
I'm not sure I understood what you said.....you mean that the test that datsunrides told me to do should be done with the battery dead as it is and not once it is charged?
What I meant was...Even if you find the battery is now dead, it may not have been defective. A draw or a poor charging system might have killed it. So get your charging system checked out and make sure you do not have a draw (spark when the second battery cable is connected, BTW: always connect the + first and the - second) or enough draw to cause the test light to light up when installing the new battery. Good luck finding it! TR
Like you mentioned, when I took the battery to get checked they told me that other than the obvious need to recharge, the battery is good. After recharged, they checked it again and it is now fully charged and operational.
I haven't hook it up to the engine yet because I took the alternator out to give it a quick "physical exam".
Now, I have a question....I've read conflicting opinions about the volt. regulator and grounding......am I supposed to make sure it has a grounding metal-to-metal surface to ground with the body (when screwed on the engine bay), or am I supposed to put some rubber to insulate the volt. reg. from the body?
I had a similar problem on my 1964 Ranchero. The voltage regulator would stick open sometimes, and shut sometimes. When it stuck open it wouldn't charge, and when it was stuck shut, it would overcharge, and the generator would try to turn the engine over. A solid state regulator is different, but it sounds like that is the problem. Hope you get it fixed.
I would think that the body needs and possibly wants to be grounded. The only reason it wouldn't want to be grounded is if there was a short inside the casing. The 510 charging system is essentially the same, and the stock wiring harness has a ground lead that connects to the screw that holds the regulator in place...
So, now you know the battery is good, make sure you don't have a draw and that you are charging and you will be ready to go!
this is really kind of dumb, but i was having the same problem, and as the car was not going any were in between my attempts to play with it , i never noticed that the brake lights were stuck on. a bit of tweeking on the brake light switch and no more dead battery. good luck, chris
The grounding of the regulator case has nothing to do with your problem, only if the regulator is completely shorted internally. The ground comes through the black wire.
datsunrides has the same basic idea as follows.
Do you own a DVOM ? or can you borow one? If so, fully charge the cars battery, hook up the positive cable and the set the meter to DC AMPS and hook one probe to the neg. post on the battery and the other to the neg. cable end. The normal reading should be around 25-250ma depending on what you have electronic wise in the car( clock, radio,etc..), so the test light method will always show the light to shine even if its normal parasitic draw. If you have a draw which kills the battery in very short time, you will be looking at a draw over a couple of amps or more. If you have a draw, start pulling fuses till it goes away, you will then narrow your search. You can also unplug cables if you run out of fuses. When using amps to diag. a electric problem, you can tell what is drawing by the amount of amps displayed.
