3 alternators in less than 6 months

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Logan01

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Hey I have a 1981 Chevy K10 with a 350. I have 2 12inc subs in the back drawing 500watts. Somehow I've burned out two brand new alternators and the original and I can't figure out why or how. Iv also had problems with my lights flickering after a 15-20 min drive if that help.
The original alternator was 63amps second 150 and the third was 160.
Any advice or pointers would be greatly appreciated.

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Blue Ox

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Is the wiring big enough to handle the amperage you're pulling. There's tables to determine total circuit length vs amperage and what gauge wire you need.
 

Jethro224

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Are you buying your alternators from AutoZone?
Last one I bought there lasted @6 months. Warranty replacement lasted 6 months. Warranty replacement for the replacement lasted @6 months...
AutoZone employee said "Why do you care? It's free."
Pissed me off and I got a refund. I don't like fixing the same thing over and over. Haven't bought anything from them since.
 

MisterB

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Are you buying your alternators from AutoZone?
Last one I bought there lasted @6 months. Warranty replacement lasted 6 months. Warranty replacement for the replacement lasted @6 months...
AutoZone employee said "Why do you care? It's free."
Pissed me off and I got a refund. I don't like fixing the same thing over and over. Haven't bought anything from them since.
That's ridiculous for them to say. As though breaking down on the side of the road, and then having to get towed, remove the old part as core for the exchange, go to the store to exchange the part, head back home and take the time to install the part FOR THE THIRD TIME is no big deal. The lack of common sense with some folks is staggering.

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Logan01

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Are you buying your alternators from AutoZone?
Last one I bought there lasted @6 months. Warranty replacement lasted 6 months. Warranty replacement for the replacement lasted @6 months...
AutoZone employee said "Why do you care? It's free."
Pissed me off and I got a refund. I don't like fixing the same thing over and over. Haven't bought anything from them since.
No I got the first one from JBS power and the second from Sumit racing. Both are going under warranty but like you said it's a pain to replace it all the time even if it's a free replacement.

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Logan01

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Is the wiring big enough to handle the amperage you're pulling. There's tables to determine total circuit length vs amperage and what gauge wire you need.
I'm running 4Gage exactly how it says in the instructions so it shouldn't be the problem.

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Vbb199

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500 watts shouldn't be enough to fry an alternator....

I ran 1500w on an alternator for a while... 1 amp, two 12s.


HOWEVER, the lights quit dimming and sound quality went up after I installed a capacitor.
Originally a 4 farad.

Over time the setup grew, became 3500w, four 12's, two 15's, about 12 farads of capacitance.... Still running the same alternator... Lol

What's the power output of that alternator??

I'd suggest you get yourself SOMETHING to store juice for the deeper hits.

1 farad = 500w of power

Get yourself something like a 2 farad cap, something as that will just as easily save the alternator from quitting.
 

Vbb199

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Or optionally, you just have a bad battery, I still think you need a capacitor
 

HOTFOOT

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That's ridiculous for them to say. As though breaking down on the side of the road, and then having to get towed, remove the old part as core for the exchange, go to the store to exchange the part, head back home and take the time to install the part FOR THE THIRD TIME is no big deal. The lack of common sense with some folks is staggering.

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Good job, bad job still getting paid the same so why do a good job!!! And they want 15.00 per hour, go figure
 

Logan01

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500 watts shouldn't be enough to fry an alternator....

I ran 1500w on an alternator for a while... 1 amp, two 12s.


HOWEVER, the lights quit dimming and sound quality went up after I installed a capacitor.
Originally a 4 farad.

Over time the setup grew, became 3500w, four 12's, two 15's, about 12 farads of capacitance.... Still running the same alternator... Lol

What's the power output of that alternator??

I'd suggest you get yourself SOMETHING to store juice for the deeper hits.

1 farad = 500w of power

Get yourself something like a 2 farad cap, something as that will just as easily save the alternator from quitting.
Ok I'll give that a try I think I'm going to take it to my local mechanic just to check thing out anyways.

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gotyourgoat

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This sounds battery or maybe ground related. Tell us about the battery are you running.
 

Logan01

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This sounds battery or maybe ground related. Tell us about the battery are you running.
It's only about 2 years old but it was the cheapest crappy tire offered at the time so it could be. How would I go about checking?

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Vbb199

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It's only about 2 years old but it was the cheapest crappy tire offered at the time so it could be. How would I go about checking?

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If your headlights get brighter when you Rev the motor up, it's a ****** battery, since you've been thru 3 alternators now.....


But evidence has shown... Auto parts stores sells **** alternators.... Right @bigcountry78 ?

(he went thru multiple alternators in short order until they have him one worth a damn)
 
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bigcountry78

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If your headlights get brighter when you Rev the motor up, it's a ****** battery, since you've been thru 3 alternators now.....


But evidence has shown... Auto parts stores sells **** alternators.... Right @bigcountry78 ?

(he went thru multiple alternators in short order until they have him one worth a damn)
Yes, replaced my four year old unit on a Wednesday. Drove to my parents house that Friday, it started over charging. Took it back, got another one, had them test it, another one over charging. Left advance, went to oreilly, turned the new over charging one in and got another one, had it tested, and it’s in the truck now. So three alternators in three days.
 

gotyourgoat

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I use my charger to gauge battery life or lack there of. Judge by volts and ability to hold a charge.

The winter before last I went through 6 batteries between 3 cars. Half of those were sealed top batteries so even fresh batteries come doa. It's not just alternators.
 

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