I guess setting up a rule that says replace at XXXX number of miles or a
certain time period would likely prevent failures.  Thats how Honda does it
on their new vehicles and it seems to work pretty well.

However, in the case of the charging system, I think we can be a little more
scientific.

Pull the brush assembly out of the alternator if you think that it is
surviving on borrowed time.  Check the amount of brush material left.  If
theres not much, replace the brushes.  

In my experience, anything after 160000kms would fall into that category.
While you have it apart, inspect the bearings for wear.  Any play and it
should be replaced.  For the $10 or so in parts, I would say its well worth
it.  Getting your battery load tested after its on 'borrowed' time is
probably not a bad idea either.  Just ensuring a battery is in good shape can
prevent major failures of the charging system in the future.

Just a note that if its the first time you are pulling out your alternator,
it may take longer than it should.  Now that I know what I am doing on my 98
civic, i can have it out in less than 15-20 minutes. (no exaggeration).
Disconnect the battery, jack the car up, undo the tensioner, disconnect the
power lead, unplug the harness, undo the pivot bolt, and remove the
alternator bracket attached to the engine block (2 bolts).  It practically
falls out into your lap (or onto your head depending on whether you are
expecting it or not)  :)

Once its out, the only trick is to ensure you have a method of removing the
pulley bolt on the alternator.  Impact works really well.  Then you can use
an impact screwdriver to undo the housing bolts, and your in business.

Terry, sounds good to me. Have you a maintenance schedule
that seems to have been effective you for your cars'
alternators? Like replace brushes and bearings every 100k
miles/7 years? Replace battery every five years?

My theory on alternators is that little components wearing down can lead to
primary failure of expensive parts.

IE if you brushes wear down, they will cause voltage fluctuations which are
hard on the regulator.  So if you leave it too long, brushes wearing down
could cause an imbalance and be responsible for the regulator failure.

OR

My example of the output shaft bearing being shot, causing the rotor to spin
off center and dig into the stator assembly.  Small part leads to big failure.

Also consider that pretty much any time you do an alternator, if your battery
is more than 3-4 years old, you might as well replace it, cuz a bad battery
can cause a new regulator to go bad.

The alternator is not designed to charge a battery, and its not designed to
power a system that is being dragged down with a battery that is not at full
capacity.

my two bits....

Terry

This sounds like a good "exploration" project for when my
current alternator hits 80k miles or so of usage, like this
summer. I certainly remember seeing a lot of posts at the
two honda newsgroups about DIY-ing the brushes.

I see from the parts sites and my Chilton's that there will
be both a regulator and a rectifier assembly (I know;
"duh"), each of which is well over $100. Whereas the whole
alternator (rebuilt?) goes for under $200. From other
evidence, I'm betting it's rebuilt, and the only new items
on it are new brushes and bearings.

A quick google search turns up some sites saying regulator
failure is the main reason alternators fail. But many other
sites say the brushes wear down too short, and worn brushes
are the main cause of alternator failure. Some sites and
newsgroup folks mention lives of around 80-100k miles for
brushes. Of course, there must be a guesstimated time limit,
as well.

I see brushes (two) and bearings (front and rear) go for
about $6 and $16, each, respectively, at the usual online
OEM honda parts sites. So I'd like to see if I can locate a
shop, along the lines of what T L says, that sells these.
Again, as an exploration; for fun and learning.

My original alternator died (or parts within it died) at
106k miles and 8 years. I don't know whether they put in a
remanufactured alternator or a whole new alternator, but
I'll ask what my current local dealer does next time I'm
there.

All comments read, Butch Burton, TL and Mike. Thanks for the
input.

i imagine the brushes might be able to be replaced, somehow. maybe the
diodes or rectifier or something? but basically thats just rebuilding it
yourself.

could also take a voltmeter reading before going on a long trip. still,
thats no guarantee, and not really PM, either.

What do you (anyone?) suggest for alternator preventive
maintenance?

I am a big believer in PM - so what kind of PM do you do on an
alternator?

This same thing happened to me years ago - still remember the glint in
the eyes of the AH when I came in the crooks place.  He used a BS
rebuilt in mine.

Dpending on the mechanic's rate and the type of replacement part he used, you
probably did on the high side of OK.

The job takes at least an hour, maybe 1.5 by book time standards.  A Honda
replacement can cost upwards of $215 (according to SLHONDA.COM), aftermarket
I have found to be about the same or more (at least here in Canada for a
Bosch unit).  Bosch offers a 5 year warranty up here, that is probably the
reason for the premium.  You probably don't want the cheaper rebuilts, they
only replace what is broke, and not the items that could be worn.

However, you take your life into your hands anytime you pull this kinda thing.
Understandable if you are in the middle of a roadtrip, it had to be done, but
you should avoid this kind of problem like the plague by doing Preventative
Maintenance.  Mechanics can smell desparation from miles away.

t

I got it changed for $291 US this weekend during a road trip (no time to
compared prices; didn't want the car to break down). Did I get raped or did
I get a fair price? (Austin, TX)