The alternator is not what holds a charge; that's the battery's job. Itessobill said:my car quit charging,,,, i bought a new altenator but it wont charge
still,,,,, i hear a relay clicking and it charges,,, but it quits quick,,,
i really need help with this prob,,,, i am taking it across canada in a few
days,,, and i cant find the prob at all
I read somewhere that it's best to replace the battery and alternator
at the same time. A bad alternator can ruin a good battery and vise
versa.
But this isn't true for more expensive cars like Lexus and BMW.
Mike said:Don't know where you read it, but it's wrong. It's not even true for
the most inexpensive cars. This sounds like the kind of advice one
hears on the DIY type channel on TV...
Screwtape III said:If a car battery is more than two years old I can see replacing it
along with a bad alternator, just to keep from having to mess with the
charging system again sometime in the near future.
Mike said:As a proactive preventative measure, I suppose so, but I always get
way more than two years out of my batteries. I live in upstate NY
where summer can be pretty hot (but not like AZ), and winter can be
as cold as you need to put a battery to the test. If I had to guess,
I'd say I probably average 5-6 years on a battery. At that point the
winter weather will generally show what shape the battery is in.
My truck is a '94 and it really only gets occasional use anymore. It
plows a lot in the winter but in the summer it can sit for three
weeks without ever being started up. In the winter, it's usually
started within two weeks since we seldom go that long without
snowfall. It sits outside, no engine block heater or anything like
that. The battery is at least 6 years old and it doesn't even think
twice about turning that 350 over on the coldest of days.
I just replaced the factory battery in my daughter's 2000. It
finally hit the point where it didn't take much to run it right down.
It would start the car ok under any conditions but if you left a door
open for any amount of time at all, it would drain down to the point
that it couldn't supply the starter. I threw in a battery that had
been in another car of mine for 5 years. One of my other daughters
had totaled the car and it was quite convenient that the battery
problem in the 2000 popped up when it did, as I was able to pull the
battery out of the totaled '98 before they towed it away. So far,
it's performing well. If it fails within any short period of time I
won't really complain - I've already gotten a useful life out of it
so anything from here on out is just a bonus.
Screwtape III said:It sounds like batteries last a lot longer in New York than they do
down here in Florida. I just replaced the battery in my son's 2000
Accent for the 2nd time. The summer heat combined with engine heat can
really cook a battery.
As a proactive preventative measure, I suppose so, but I always get way more
than two years out of my batteries. I live in upstate NY where summer can
be pretty hot (but not like AZ), and winter can be as cold as you need to
put a battery to the test. If I had to guess, I'd say I probably average
5-6 years on a battery. At that point the winter weather will generally
show what shape the battery is in.
My truck is a '94 and it really only gets occasional use anymore. It plows
a lot in the winter but in the summer it can sit for three weeks without
ever being started up. In the winter, it's usually started within two weeks
since we seldom go that long without snowfall. It sits outside, no engine
block heater or anything like that. The battery is at least 6 years old and
it doesn't even think twice about turning that 350 over on the coldest of
days.
I just replaced the factory battery in my daughter's 2000. It finally hit
the point where it didn't take much to run it right down. It would start
the car ok under any conditions but if you left a door open for any amount
of time at all, it would drain down to the point that it couldn't supply
the starter. I threw in a battery that had been in another car of mine for
5 years. One of my other daughters had totaled the car and it was quite
convenient that the battery problem in the 2000 popped up when it did, as I
was able to pull the battery out of the totaled '98 before they towed it
away. So far, it's performing well. If it fails within any short period of
time I won't really complain - I've already gotten a useful life out of it
so anything from here on out is just a bonus.
1. I believe the failure mechanism on lead acid storage batteries is
largely a matter of charge/discharge cycles so long life from a seldom
used battery is not surprising. Capacity also drops with use if the
cells don't short out first. AFAIK the lead plates break down
creating sediment that collects in the bottom.
2. The battery/alternator tie in would be if the regulator let the
alternator overcharge the battery to failure where it shorted and took
out the alternator diodes. Ditto if the battery shorted and cooked
the alternator. The bottom line is that it pays to check both but you
may not need both. It depends on what failed in the alternator.
Before regulators were incorporated in the alternator it was
reasonable to replace the regulator and alternator/generator as a
pair.
Screwtape said:It sounds like batteries last a lot longer in New York than they do
down here in Florida. I just replaced the battery in my son's 2000
Accent for the 2nd time. The summer heat combined with engine heat can
really cook a battery.
Geo said:I always thought the clicking or no sound was the result of a bad
starter.
An alternater will regularly stop giving energy when you
stop giving gas, like stop lights/signs/braking for any reason.