Battery/Alternator..........what what!!

[73Bird]

Ok....recently had my battery replaced cuz it was crap. My lights and washers were dimming while car running prior to replacement. I Had my alternator checked by FNG at the auto parts store the day before. Alternator was said to be good. Now it starts right up with a jump but wont restart. I tried the screwdriver to the back area of alternator while running-------no magnet whatsoever........also disconnected the positive terminal while running...........car dies immediately. I think its safe to say FNG didnt know what he was doing while testing or maybe it was running off one diode and now its finally toast. Just ripped alternator again......wait for a reply or two before I just go buy a new one.............which is what I initially set out to do anyway.............let the games begin!

 

[Cranky]

Have you had the regulator checked? It could also be something simple like it's not grounded....

 

[73Bird]

Cranky,

Is that the off white rectangle in the center of the firewall with wires on it? Im def a rookie. Not afraid to dive in.........just not sure what that is. duh.....sorry. Any input would be nice. Would my alternator NOT have a magnetic pull with a bad regulator? Thannks for your input

 

[Mopars & Missiles]

Basically, the regulator tells the alternator when to charge and how much to charge. The regulator turns the alternator on and off.

The regulator monitors the battery voltage, then either increases or decreases the output of the alternator depending upon the electrical demand of the entire system at that point in time. It does this by changing the current through the field coils of the alternator. When the windings of the alternator (rotor) rotate through the magnetic field created by the (stationary) field coils of the alternator, an AC voltage (and thus a current) is induced and then rectified by diodes internal to the alternator (creating 13.5-14.5VDC) before traveling back to charge your battery from the big stud on the back of the alternator.

Realize that this is the simplified explanation, but should help you visualize what the circuitry is doing.

So, No your alternator would NOT have any magnetic pull if the regulator has it completely shut off.

 

[73Bird]

Awesome thanks........then I will re install the alternator and replace the regulator first. It probably could use a new one due to age anyways. Thanks a bunch guys, appreciate it. Great explanation as well. :headbang:

 

[68 Sport Satellite]

Cranky,

Is that the off white rectangle in the center of the firewall with wires on it? Im def a rookie. Not afraid to dive in.........just not sure what that is. duh.....sorry. Any input would be nice. Would my alternator NOT have a magnetic pull with a bad regulator? Thannks for your input

Nope - the white ceramic piece you mention is the ballast resistor. Those are known to go bad too, but you will know that's bad if you start the car and when you release the key the motor dies.

The voltage regulator is the black rectangular box mounted near the ballast resistor on the firewall. The old one's are mechanical and change resistance when they heat up if I remember right. Do yourself a favor and buy one with newer style solid state innards. It looks the same from the outside case but works more reliably, consistently, and lasts longer. Also carry a spare ballast resistor in the trunk. Usually a 1 ohm will do. If those go out they will leave you stranded. If you try to bypass the ballast resistor you may make it on a short drive home but too long and you can fry your ignition.

While you are changing the voltage regulator, you may as well change the coil, the cylindrical piece with wires on one end and mounted in a sleeve clamp. If yours is older than ten years, sometimes these can leak oil or get a crack in the case that lets moisture in and give similar hot starting problems. Ask me how I know all this! I just went through my own trouble-shooting a year ago.

 

[73Bird]

Ok you guys need to stop. Im actually learning something. lol. After your email I went and looked at these parts and found them with your guidance. Good Idea, I will order a spare and also replace my coil. It appears 10 years or older. Some of this stuff looks original so if their are any upgraded parts to replace the OEM I will go with those as mine is a driver and not show. Thanks for your input. Im getting some verbage down now. lol.

 

[73Bird]

Ok while Im in that electrical mode there is a gadget with a screw post, 2 snap in and one nut connection just above the master cylinder. It has wires going to battery. It probably could use replacing while Im doing this. Any ideas what it is before I go take a pic of it? Thanks

 

[Mopars & Missiles]

Ok while Im in that electrical mode there is a gadget with a screw post, 2 snap in and one nut connection just above the master cylinder. It has wires going to battery. It probably could use replacing while Im doing this. Any ideas what it is before I go take a pic of it? Thanks

Well, don't know exactly what car you have. Maybe a '73 Road Runner from your screen name? Regardless, it sounds like you are describing a Starter Relay but don't know for sure without seeing what you are referring to. On my cars, the starter relay IS NOT above the M/C, but it very well could be on yours.

If your car always cranks when you turn the key, there is NO need to replace the starter relay now. Just throwing good money away on unnecessary parts.

If it ain't broke, don't FIX IT. :head_smack:

 

[Ron 73]

seat belt buzzer maybe? The white ceramic thing is the BR as said, it gives you about 7 volts when the key in on run, 12 volts needed to start the car when in cranking position. If you want to check it put a test light on positive side of coil and ground the other side, when in run position it should be bright, turn key to crank it should be brighter yet. Balist resisters, as said do go bad.. Pictures would help identify parts better.

 

[73Bird]

1973 Satellite w/360. Thanks for all your input......I have replaced the battery last week....today, the voltage regulator and had my alternator tested 2x today. The car wont hold a charge, will jump start right away but wont restart on its own. It idles for 5-15 minutes then dies. I did notice today, I forgot to disconnect the battery while reinstalling the alternator. I saw a spark so hopefully I didnt fry anything. duh! Im pulling the battery in the am to make sure I didnt get a **** new battery and have it charged. THen Im looking at fuses..........any other suggestions? Kinda at my wits end. Spent all feaking day on it and watched my friend drive by on his way to hot rod night n beers. Its great! lol.

 

[Ron 73]

Id like to ask you if the amp meter in your car, amp/volt, does it show a steady discharge when its running before it quits, You said it runs 5-15 min and then dies, and im assuming then the battery is completely dead. I bought a battery at Auto zone years ago and it was a kind of pricey one for back then, my ford would only stay charged a day or so and was just worn out, i brought the new one home and it wouldn't work, took it back, they checked it and told me there was nothing wrong with it, i asked for a different battery and the problem was done, but that don't happen often, but it does happen, maybe not your problem and if its discharging that fast, it sounds like a real bad short, with your key and everything off it shouldn't spark at all when you put the cables on battery, i would check that.. Just a suggestion.

 

[73Bird]

Thanks Ron..........think Ill pull the battery tomorrow and have it checked. With all the jumping and pulling different parts etc.....Im sure it could used a charge even though its new If that doesnt work Ill start checking for a short up front. I appreciate your help.

 

[wannadrag]

I would bet the battery tests good.I am thinking bad alternater.

 

[73Bird]

hmmm, but why is it testing good? I tested it a few weeks ago. Took it out today and had the guy check it 2x and it checked out? Im lost on this one. lol. Oh well.........use up my Sunday tomorrow playing around with it again. Unless I have a bad short........gonna try to find that tomorrow. You do have me thinking pull the damn alternator again and just replace it. Peace of mind and they arent that expensive. I also broke the bolt off in the old one and having a hell of a time trying to get the right tension on the belt. Maybe THATS a problem too.
:headbang:

 

[Ron 73]

Thats possible depending on how loose it is.. Trying to trouble shoot these problems do end up getting a headache for sure.. When you charge your battery up to a full charge and start your car, check your amp or volt meter and see what its telling you, If its discharging that bad it should show up something, id check it before you start your car, see what it says with the key on first then start it and see what its doing.. Im just kind of assuming you have some kind of a volt or amp meter in it, if not, i would get a volt meter to hook up so you can keep track even in the future.. I know its frustrating, ive been down this electric crap problems a few times myself sorting out problems. Good luck.

 

[73Bird]

Thanks........will check all that tomorrow. My voltage in the dashboard shows right in the center........so that looks good. Pulling out the voltage:headbang: meter and the battery in the am. See what happens.

 

[73Bird]

Gentlemen, Thanks for all of your help. Had the new battery recharged today. Tapped the old alternator to remove broken mounting bolt and gave it a new one, was gonna be lazy and just spend 60 bucks on a new one, glad I did the work. Found my short......unreal. Replaced all the wires to the alternator with brand new ones after finding some pretty rotten stuff rigged on firewall. Started first crank and she purrs like a kitten. MEOW!!!

 

[Ron 73]

Enjoy!

 

[68 Sport Satellite]

Right on! You have one thing going for you for sure - you tackled this problem right away and ended up with success. That doesn't always happen this quickly, especially with electrical issues. Many times most of us are so busy that this car hobby takes a back seat and troubleshooting something like this can turn into weeks or months because we can't get back to working on the car right away and then we may forget the advice someone gave us. Glad to hear this one worked out for ya.

Oh, and that small box near the brake master cylinder is indeed the starter relay. It should be fine.