C8 alternator

[gpm]

I was watching a YouTube Corvette c8 guy and he said the alternator on the c8 does not charge the battery only maintains systems while car is running. I was wondering if this is true cuz I've never used a battery tender does that mean I've never charged my battery since I bought the car. I put a tender on it last night it was on the first light for quite a while. Overnight it finally reached full charge. From my point to a question is is this guy correct and the alternator does not charge the battery while drivin?

 

[Murray20c8]

It will charge the battery. It's just like any other alternator on any other car. It's more than capable of doing it just as well or better than a maintainer. They are typically at least capable of 50 amps. Way more than your typical maintainer.
That said they are smart alternators and are designed to keep the battery charged. It doesn't mean it doesn't or can't charge a battery. I only use the maintainer if the car will sit for a week or more.

 

[gpm]

It will charge the battery. It's just like any other alternator on any other car. It's more than capable of doing it just as well or better than a maintainer. They are typically at least capable of 50 amps. Way more than your typical maintainer.
That said they are smart alternators and are designed to keep the battery charged. It doesn't mean it doesn't or can't charge a battery. I only use the maintainer if the car will sit for a week or more.

So what you're saying is, for example, if I were to take a month-long trip driving I don't need to bring the tender with me

 

[Murray20c8]

So what you're saying is, for example, if I were to take a month-long trip driving I don't need to bring the tender with me

If you drive the car regularly you do not need a tender. We drive ours 3 times a week. If you drove to a motel in Florida and didn't drive the car for 2 weeks you'd still be OK. The parasitic drain on a C8 battery is negligible over a 2 week span,

 

[1st Vette]

I was watching a YouTube Corvette c8 guy and he said the alternator on the c8 does not charge the battery only maintains systems while car is running. I was wondering if this is true cuz I've never used a battery tender does that mean I've never charged my battery since I bought the car. I put a tender on it last night it was on the first light for quite a while. Overnight it finally reached full charge. From my point to a question is is this guy correct and the alternator does not charge the battery while drivin?

I connect my battery tender , the “ Corvette “ branded one, every time I park at home. I’ve noticed the same thing every time as well that when first connected it shows the lowest of the four charge states for maybe 10 seconds then goes to the second lowest. Not sure how long it takes to get to the 3/4 mark or full but may check that out. Only takes 15 seconds to open the frunk and plug it in so why not. Can’t hurt. I suspect that if the tender indication is correct then it could be an issue for very cold, like -30 starts but then again that would be very few owners. Hi Jack ….

 

[Murray20c8]

I'll add that most maintainers are at most 6 amps. That is why it takes so long to charge it. It starts high, but drops down to lower amperage and takes longer to fully charge. When you park your car the battery is fully charged! Unless, of course, there is a problem with your battery.

 

[1st Vette]

I'll add that most maintainers are at most 6 amps. That is why it takes so long to charge it. It starts high, but drops down to lower amperage and takes longer to fully charge. When you park your car the battery is fully charged! Unless, of course, there is a problem with your battery.

Hmmm, just curious. When was the last time you did a load test or checked the voltage on your battery right after parking it ? Might be surprising. You never know. But like I said it can’t hurt to use one as far as I know. I’ve always used one on my vehicles and have had batteries last 8 years or so in a daily driver. And here that means a lot of-30 and -40 starts . And their output current depends on the state of charge in the battery but yes it’s not very high. . But to each their own.

 

[Murray20c8]

Hmmm, just curious. When was the last time you did a load test or checked the voltage on your battery right after parking it ? Might be surprising. You never know. But like I said it can’t hurt to use one as far as I know. I’ve always used one on my vehicles and have had batteries last 8 years or so in a daily driver. And here that means a lot of-30 and -40 starts . And their output current depends on the state of charge in the battery but yes it’s not very high. . But to each their own.

The Alternator keeps the battery fully charged.
I've never used a maintainer on any car except the C8 and have most of my batteries last 8 years or so.

 

[C8 route66]

The charge algorithm varies depending upon various factors. Normal daytime driving upon startup it, it charges to ~14.5 volts. After a short time, the voltage will drop back to approximately 12.7 volts. Have observed the voltage swinging between 12.3 to 14.7 volts. This is supposedly normal. With the lights on at night time it should charge to 14.3 volts or so. The lower voltages are for fuel economy.

 

[1st Vette]

The charge algorithm varies depending upon various factors. Normal daytime driving upon startup it, it charges to ~14.5 volts. After a short time, the voltage will drop back to approximately 12.7 volts. Have observed the voltage swinging between 12.3 to 14.7 volts. This is supposedly normal. With the lights on at night time it should charge to 14.3 volts or so. The lower voltages are for fuel economy.

Just curious as to how “ lower voltages “ can affect fuel economy. Next time I come back from a long cruise I am going to pop the battery cover panel off and check the battery voltage while the engine is still running and then after shutdown. Should be interesting. 12.3 to 14.7 does seem normal. Where or how did you get those readings ?

 

[C8 route66]

Just curious as to how “ lower voltages “ can affect fuel economy. Next time I come back from a long cruise I am going to pop the battery cover panel off and check the battery voltage while the engine is still running and then after shutdown. Should be interesting. 12.3 to 14.7 does seem normal. Where or how did you get those readings ?

The voltage reading were from the dash display.

 

[Jack Raccoon!]

I connect my battery tender , the “ Corvette “ branded one, every time I park at home. I’ve noticed the same thing every time as well that when first connected it shows the lowest of the four charge states for maybe 10 seconds then goes to the second lowest. Not sure how long it takes to get to the 3/4 mark or full but may check that out. Only takes 15 seconds to open the frunk and plug it in so why not. Can’t hurt. I suspect that if the tender indication is correct then it could be an issue for very cold, like -30 starts but then again that would be very few owners. Hi Jack ….

I've started my car at least 5 times at -30C with no issues and have never used a Battery Tender. Car sounded like it didn't appreciate being woken up at that temp but obliged anyway lol...

 

[1st Vette]

I've started my car at least 5 times at -30C with no issues and have never used a Battery Tender. Car sounded like it didn't appreciate being woken up at that temp but obliged anyway lol...

I don’t like being woken up at -30 either……