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Discussion Starter #1
Guys I need soem help. My SVTF is draining my battery. I had a yellow top Optima and without any warning it was done. So I push start the car go to the Advanceauto parts they test the battery and alternator. Alterntor charges fine but the battery is done. I get a replacement yellow top Optima battery. It worked fine for around a week. I did not use the car for two days, went to start the car and again the battery is done. Anyone had this problem? All my fuses are good, alternator was fine. Any input will be apreciated.
 

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Our alternators are bad about going out, mine went through a 5 month dying period and when got down to the end of it sometimes my car would start sometimes not. I would get the alternator tested again, it may be not putting out much of charge. If you end up changing the alternator have fun bc its a pita. (I did mine two days ago)
 

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It sounds like there's something else draining the battery, not necessarily the alternator. reason being is that you had the car off for 2 days and the battery is dead already. Try getting it tested again, but an alternator wouldn't kill a battery when the car isn't running. make sure there isn't something staying powered on when the car is shut down.
 

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I totally agree with what he said up there...When the car is shut down it shouldn't pull more than .oo5 amps or 5 milli amps there is a simple test for this but......you need to test the battery, make sure they are load testing the battery correctly as in, it must be to 12.45volts or higher, load test at half the CCA of the battery and it shouldn't drop below 9.6 volts, if it does, its toast otherwise, its fine and the new charge should hold you for a while. Like i said i can help you do a "parasitic drain" test if you would like, just pm me....you will need an ampmeter or a multimeter. and if you pm me we can possibly tlk on the phone and i can help you further with this problem you're having, there are some other possibilities i THINK but i will have to ask you further questions...

Andrew
 

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Discussion Starter #5
It sounds like there's something else draining the battery, not necessarily the alternator. reason being is that you had the car off for 2 days and the battery is dead already. Try getting it tested again, but an alternator wouldn't kill a battery when the car isn't running. make sure there isn't something staying powered on when the car is shut down.
Yes I agree. My son has been starting the car for me almost every other day. He just left it alone for two straight days and it killed the battery. He told me he left nothing on, and the same thing happened to me after driving to take a test. After an hour I went to start the car and nothing, so I know it wasnt anything he did. I am trying to get as may info as can so I appreciate the info.
 

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Discussion Starter #6
I totally agree with what he said up there...When the car is shut down it shouldn't pull more than .oo5 amps or 5 milli amps there is a simple test for this but......you need to test the battery, make sure they are load testing the battery correctly as in, it must be to 12.45volts or higher, load test at half the CCA of the battery and it shouldn't drop below 9.6 volts, if it does, its toast otherwise, its fine and the new charge should hold you for a while. Like i said i can help you do a "parasitic drain" test if you would like, just pm me....you will need an ampmeter or a multimeter. and if you pm me we can possibly tlk on the phone and i can help you further with this problem you're having, there are some other possibilities i THINK but i will have to ask you further questions...

Andrew
I am overseas right now but I can have my brother check it out for me. The battery is less than a month old Yellow top Optima. I would really appreciate the help on the test. I can ask my brother to go through the steps as you recommend. Hi is very mechanically inclined just not very famiiar with the SVTF. I you would, post the process here or on my PM, thanks Anderw.
 

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I have had an issiue with batteries dieing like that in another car and a friend of mine told me he had that problem with his ford and when replaced his altanator the problem went away. it might not be completely discharging when it is shut off so consecuently it drainse the battery. but it charges fine and tests like a good altenator.
 

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not true an alternator can draw a battery down with the key shut off, there are several ways it can, most noticable is the ever common bad diode which allows AC voltage leakage, and can potentionaly damage a brand new battery in days.

an other lesser known problems are a faulty rotor/stator grounding out, causeing abnormaly high voltages and sometimes you'll hear a ticking sound comming from the alternator on a test bench, and be red hot to the touch. aswell as your draw

and on some occasions which ive personaly seen is an open regulator causing voltage leak, and high charge voltages. and a draw

and an almost never seen problem is a bad alternator light switch the "L" terminal inside of a regulator, symtoms being no alternator fault light. but high parasitic draw rates, this is very rare on chevy delco si/cs series alternators with alt lights.

on a side note, when i test batteries i test them at the cca rating, not half.
testing only half the rating of a battery isnt a good idea. you run the risk of not condeming a bad battery or a battery that will fail on you when the next cold or heat front moves in and wipes out your already weak battery, of course when i test a battery, we use a detac, or sun vat45 and or a handheld conducance/load meter.
which if i had to guess might test internaly at half the rated cca. but everytime the testing machine is calibarated for aprox temp and cca at zero degrees. :)
 

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on another side note a fully charged battery, with an internal sp gravity of 1300 should read 12.9 volts. you could charge a battery for an hour or 2 and get it to read 13.2-3 volts and it still wouldnt be fully charged, all your doing is putting a suface charge on it, which would burn off in 15 seconds on a good christi load test. and leave you 2-3 hours of more charging that you have to do on top of an overnight charge. :/ and while load testing a "fully charged battery" the voltage shouldnt read past 10.9 volts. though i cant see a differance from 10.9v 9v *shrug*
 

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Discussion Starter #10
not true an alternator can draw a battery down with the key shut off, there are several ways it can, most noticable is the ever common bad diode which allows AC voltage leakage, and can potentionaly damage a brand new battery in days.

an other lesser known problems are a faulty rotor/stator grounding out, causeing abnormaly high voltages and sometimes you'll hear a ticking sound comming from the alternator on a test bench, and be red hot to the touch. aswell as your draw

and on some occasions which ive personaly seen is an open regulator causing voltage leak, and high charge voltages. and a draw

and an almost never seen problem is a bad alternator light switch the "L" terminal inside of a regulator, symtoms being no alternator fault light. but high parasitic draw rates, this is very rare on chevy delco si/cs series alternators with alt lights.

on a side note, when i test batteries i test them at the cca rating, not half.
testing only half the rating of a battery isnt a good idea. you run the risk of not condeming a bad battery or a battery that will fail on you when the next cold or heat front moves in and wipes out your already weak battery, of course when i test a battery, we use a detac, or sun vat45 and or a handheld conducance/load meter.
which if i had to guess might test internaly at half the rated cca. but everytime the testing machine is calibarated for aprox temp and cca at zero degrees. :)
Thanks for the info, but where can I find the diode in the car so that I can check it ,or how do I check for proper function? Also, I did have a ground code some time back that did not get corrected. I did the complete wire grounding kit but the code is still there.[ffrocks]
 

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Discussion Starter #11
Thanks Stooge for the PM. Wish I knew how to give rep points. To these guys.
 

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the diode, or diode trio is a part of your rectifer, which retifies AC current which your alternator creates, into DC battery power to run your car.
any shucks, or napa or a standard battery specialist would check this while doing a routine alternator check. its part of the process theres no way to miss it.

btw, to give rep points just click the persons FF reputation score, and a little box will come up.
 
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