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Discussion Starter · #1 ·
Ok i have done the electric fan mod and i really do love it, but I am having a bit of a problem. Im currently running the stock 60amp alternator and personally I think it does pretty well. I figure the relay is rated at 25amps and the electrical system is rated at 10 amps or so, so then why do i seem to be going through batteries so quickly. Well not too quick about 1 a month for the past 2 months. So basically it does great for a month and then it gives out. Essentially I have 15amps left to keep the battery charged. Is there something Im missing about the charging concept or does this seem correct. I have noticed that my alternator is currently out because when i disconnect the battery, the car turns off. Is there something else I could do besides the 3g alternator upgrade to help keep my battery charged and my fan running.
 

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Have your alt. checked and check the system for a draw.

take the (-) cable off the battery and put a test light between them, the light should not come on if everything is turned off. Make sure the doors are closed there is no hood light etc. if the light dose come on find the draw, it could be the glove box light,trunk light, regulator, etc.
Your alt should be enough.
 

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If the car dies with the battery disconnected, the alternator is not putting out.

Either the alternator or regulator (or both) are bad.

Alternators are rated at their max RPM, and in as new condition. Old ones go sour, and so do the old style mechanical regulators.

When my alternator died on my Torino I upgraded it to 80 amps for less than $40.00 by purchasing the upgrade kit from the folks in the link above.

$40.00 for an 80 amp alternator seems like a good deal to me!

Greg
 

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80+ amps, 100+ is even better. You don't have 15 amps left. Remember all that other stuff takes power to. Especially an electric fuel pump, stereo and dist. At idle you probably are putting out only 17 amps.
 

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5 - 15 amps for a stock ignition, a little more for MSD... depending on the RPM.
 

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One thing you have to remember, just because an electrical device states 15 amps dose not mean it draws 15 amps. That is the protection limits, meaning a 15amp fues will pop before it starts burning up the wiring and causing damage. A 20amp fuse on a 15amp device will most likely cause some kind of damage before it pops the breaker.

Example

My processing rack for my band
Each unit in the rack is a least rated for 15amps (because the cords are 14/2 15amp) and there are 10 units in the rack, dose that mean I need 150amp service to feed it????

I have a power conditioner that has an amp meter, I use it to feed power to the processing rack and it displays the amount of amperes I’m drawing. When I’m at full bore at a show it never draws more than 6amps, sure it will spike when you first turn things on but it never jumps more that 8 to 10 amps.

Add up all the breakers in your home service panel and then look at the main breaker, the chances of you drawing the main breakers limits are null…….

My 5 cents
 

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Discussion Starter · #8 ·
ok so then really i have more amps left over than what im expecting. Also I have no radio, no electric fuelpump, and my ignition is a DUI. I dont know if this has any correlation but awhile back the dummy alt light would flicker and my volts gauge would bounce between 15-12 volts and i never had a problem with charging the vehicle. So i decided to take the light off and now the gauge stays at 12 or less volts. what do you think about this?
 

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I think you should have your alternator/regulator checked under load by a shop. You need a constant 14.5-15 volts output put to keep the battery charged. And you should NEVER disconnect a battery cable while the engine is running! It causes a condition called Load Dump on the alternator and can burn out the internal diodes.
 

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Do you have an original style mechanical regulator (2+ " tall) or a newer electronic regulator (1" or so tall)?

The mechanical regulators used basically a set of ignition points inside to constantly buzz the alternator field with somewhere between 0 and full system voltage depending on the alternator load and RPM. Those points can fail closed or open causing severe overvoltage or zero voltage output conditions.

You really do need to get your alternator load tested, and be suspicious of the regulator as well.

Greg
 

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On 2006-10-02 05:47, torinoracer wrote:
ok so then really i have more amps left over than what im expecting. Also I have no radio, no electric fuelpump, and my ignition is a DUI. I dont know if this has any correlation but awhile back the dummy alt light would flicker and my volts gauge would bounce between 15-12 volts and i never had a problem with charging the vehicle. So i decided to take the light off and now the gauge stays at 12 or less volts. what do you think about this?
Some alternator wiring requires the resistance of the idiot light to complete the charging circuit. If you removed the bulb and now have no alternator output then I think you should put a new bulb back in.
 

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On older cars, electrical systems are pretty simple. Problems with batteries fall into only a few catagories:

bad regulator allows too much voltage/current which causes the battery to overheat and die prematurely.

Too many drains on current, which means the alternator is not servicing the current needs of electric powered components. (note: electric fans have 2 rating, startup and continuous. --- same with amplifiers ---, it soaks up a lot of 'juice' to get those items started. check your references. You may have enough to keep them running, and still be underpowered).

When it comes to alternators, you need to look at where (what rpm) they make their rated capacity. Most factory type alternators reach max at 2 - 3K rpm. If you are just driving around or idling...you may still be running on battery storage most of the time - either get a bigger battery, a stronger alternator or run in a lower gear to get the rpm's up.

Bottom line: The guys have given you real good advice. 2. If you have had to change out a battery every month for a total of 3 so far. Something is wrong. Take the advice and find the source of the problem.

Most likely solution....you need a stronger alternator. But first - check for shorts and/or gnd problems.

It really isn't that complicated.
 

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Discussion Starter · #14 ·
ok then this is what im going to do, first im gonna get a new alternator as it is still under warranty, at the same time im going to get a new regulator because I remember that it is original and is cheap enough to replace, then im gonna find that bulb and put it back on, finally im gonna move my battery to the trunk cuz it fits better back there and will give me better weight distribution. If all this fails I am going to buy that rebuild kit and be done with all these little trolls that have been bothering my poor torino. Thanks for the help and if you guys have anymore ideas keep posting and eventually this will get solved.
 

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Do not replace your alternator with a 'stock' alternator - especially if you are putting the battery in the trunk. That extra cable lenght has a resistance/foot cost that will just add to the problem.

Bite the bullet, get a high amp alternator before you start hanging cables to the trunk, You might want to look into moving the solenoid along with the battery. If you are tight on funds, aren't we all, then a 3 G kit should gett 'er done. If you can swing the green...then go after market.
 

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Discussion Starter · #16 ·
alright then, i will just get the kit to upgrade my alternator, but first im gonna replace all that i think is suspect to my problems and at a later date rework my charging system.
 

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Ok, at this point the charging system is the main suspect!

I hope you start your troubleshooting with a good test of the alternator, and replacement of the regulator.

Greg
 

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Discussion Starter · #18 ·
yeah im gonna take it to oreillys and have them check it out, while im there i will be picking up a regulator just to be safe.
 

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Mr. Just Jim has a point. The light on some cars needs to be there (needs the resistance) to make the regulator work. It states in a ll the 3G wiring conversions for early cars to put around a 500ohn resistor in one of the leads (dont remember which one) to make up for that light not being there and make the internal regulator work.

Tracy
 

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I know this:

A 1970 stock alternator with a stock old style regulator does not need a light hooked up to work.

Saw it with my own two eyes, almost 14 volts at the batt and the "I" wire wasn't even hooked up to a light.

Greg
 
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