Alternator Voltage Spec/ Battery Question

[davbell22602]

Were starting into electricity, starters, alternators, etc. at school.

He's teaching us that the alternator spec should be between 13.8-14.8 but dont exceed 15.2 volts. With a 38-140 amps. That anything not in that range should be replaced

Is that correct?

I thought GM's alternator volt rating was 14v and discard anything below 14 volts. Thats what a AutoZone worker said.

Next question

Hes also teaching us that the life span of a battery is 3 years and should be replaced. He replaces his every 3 years reguardless still under warranty from Walmart, the yellow everstart batteries.

Whatever happened to a lifespan of 8 years on a battery?

 

[Beatdown Z]

Subsribed...

 

[HotRodPC]

I've heard 13.2 to 14.2 is good voltage regulation for a 12 volt system. Normally what I see most common is 13.8 and my guages are usually a hair under 14 when working good, so I call 13.8-13.9 Optimal.

 

[HotRodPC]

I've got a Duralast battery that is 7 years old. It came in the 80 GMC I bought. I figured after sitting for 2 years it was deader than hell. I charged it up, it holds a charge just fine for several days and been using it ever since for the past close to 3 years now. That is very rare though now days. AC Delco batteries, almost like clockwork it seems, all the ones I am aware of in my family, 3 years and that's that. No sign of weakness, no warning at all. Just one day the vehicle don't start. The eye is dark and it won't charge back up.

 

[davbell22602]

14.8v seems a bit high for normal voltage on a alternator.

 

[bucket]

People that needlessly replace good batteries is why I very rarely have to buy a new one.

 

[J Knight]

I have three batterys in my Pete and regularly change them every two years, usually at the beginning of winter when we get the first cold snap. I have an amp gauge in the truck and if it doesnt fall back to almost 0 within a few minutes after I start it up, one or more are going bad.

 

[bucket]

I have three batterys in my Pete and regularly change them every two years, usually at the beginning of winter when we get the first cold snap. I have an amp gauge in the truck and if it doesnt fall back to almost 0 within a few minutes after I start it up, one or more are going bad.

That's a little different though... well, kinda.

How often do you replace it in your pickup?

 

[J Knight]

Ive had my pick up 2yrs in April, still got the bat that was in it when I bought it. So far so good, alt shows about 14 volts while running. Btw big truck is a 12v system and uses a 140 amp alt. The only difference that I can see is the extra batterys and larger starter. Seems like the concept is the same.

 

[bucket]

Ive had my pick up 2yrs in April, still got the bat that was in it when I bought it. So far so good, alt shows about 14 volts while running. Btw big truck is a 12v system and uses a 140 amp alt. The only difference that I can see is the extra batterys and larger starter. Seems like the concept is the same.

I really don't know. I just assumed that even though there's 3 batts, that they see a lot more strain during startup.

 

[J Knight]

I really don't know. I just assumed that even though there's 3 batts, that they see a lot more strain during startup.

The cables are larger and each bat has 1000 CCA and a larger starter but once it is started it operates like any other 12 system.

 

[oneluckypops]

Were starting into electricity, starters, alternators, etc. at school.

He's teaching us that the alternator spec should be between 13.8-14.8 but dont exceed 15.2 volts. With a 38-140 amps. That anything not in that range should be replaced

Is that correct?

I thought GM's alternator volt rating was 14v and discard anything below 14 volts. Thats what a AutoZone worker said.

Next question

Hes also teaching us that the life span of a battery is 3 years and should be replaced. He replaces his every 3 years reguardless still under warranty from Walmart, the yellow everstart batteries.

Whatever happened to a lifespan of 8 years on a battery?

Dave seriously, I think you should consider dropping out from your automotive school. Several members have questioned your teachers abilities. and for good reason. You are asking us to teach you from OUR experience and life lessons. By simply asking questions from your chapters. Dude if your question EVERYTHING you learn from the school why in the hell are you spending the money to complete the program?


It is NOT uncommon for trucking companies to replace Batterys on a regular service schedule. When considering the cost of service calls, down time, and late freight fines it is much cheaper to replace them early.

Oh and the Big diesel engines require the extra batterys for cranking the large HIGH compression engines.

 

[HotRodPC]

I'm not so sure he should drop out. Some education is better than none and being it's paid for already, may as well what he can out of it. After the things he's brought to our attention that the teacher has done and said, he better be second guessing the teacher. He can get a hell of an education, he can learn the worthless text book wat at school and still get some hands on while doing so, and come here and get the REAL WORLD way of doing things.

 

[crazy4offroad]

Teachers are USUALLY people who could not make it professionally on the subject they teach, for whatever reason. Physical ailment, financial situation, failure to work well with others, .... mental deficit ....

 

[HotRodPC]

That's true. The 2 auto related classes I had, the 54 hour CA emmisions tech required class, and the Begginer Auto trans class that I ended up teaching, both instructors were working mechanics but were teaching night school part time a couple nights a week. Learned an assload in the 54 hour emmisions class.
The Begginer auto trans class I didn't need, but the college required a prerequisite so I had to take it first. What a joke that was. Granted the teacher knew his ****, but he wasn't much of a teacher. He was all over the place, not following an agenda, wasn't using correct terms, skipping all kinds of ****. I was constantly backing him up, repeating his work with correct terminology. LMAO, I did literally end up at the front of the class with my OWN transmission brought from home and leading the class. Teacher was smart enough to let me and taught him several things. At the end, I gotta a biggo thank you letter from him, and how he learned to follow an agenda so the class flowwed into a good lesson from start to finish instead of back and forth. The teacher knew his ****, he just didn't now how to to put it together in a teaching method, so actually all I really taught him was how to teach so students could grasp and comprehend. I knew what the hell he was talking about and he even confused me. Needless to say, my baby girl came about and no more time for school, so that was all the auto school I ever had. The rest was learning on my own, and from the old timers.