Honda Car Forum

"Elle" <honda.lioness@nospam.earthlink.net> wrote in message
news:H1eHf.13812$rH5.6638@newsread2.news.atl.earth link.net...
> "Michael Pardee" <michaeltnull@cybertrails.com> wrote
>> I was lucky that both my cars that had that problem also had voltmeters.
>> I noticed the voltmeter in each fluctuating as the brushes made contact
>> and then didn't, but the lamps never flickered. (Sometimes they wouldn't
>> come on before start-up when the brushes were wearing out.) Talk about
>> "idiot lights!"
>
> Would you say watching the voltage across the battery terminals of an
> idling car might also likely pick up bad brushes?
>
That's how I caught it in both cases. The voltmeter fluctuated sharply
between charging and battery voltage. I think the movement of the meter
caught my eye as much as actual dash scanning did. At first it was only a
couple seconds dropout at a time, worsening to a minute or so good and a
minute or so bad within a week. In both cases the dropouts were worse when
cold.

Mike

"Michael Pardee" <michaeltnull@cybertrails.com> wrote
> "Elle" <honda.lioness@nospam.earthlink.net> wrote
>> "Michael Pardee" <michaeltnull@cybertrails.com> wrote
>>> I was lucky that both my cars that had that problem also had voltmeters.
>>> I noticed the voltmeter in each fluctuating as the brushes made contact
>>> and then didn't, but the lamps never flickered. (Sometimes they wouldn't
>>> come on before start-up when the brushes were wearing out.) Talk about
>>> "idiot lights!"
>>
>> Would you say watching the voltage across the battery terminals of an
>> idling car might also likely pick up bad brushes?
>>
> That's how I caught it in both cases. The voltmeter fluctuated sharply
> between charging and battery voltage. I think the movement of the meter
> caught my eye as much as actual dash scanning did. At first it was only a
> couple seconds dropout at a time, worsening to a minute or so good and a
> minute or so bad within a week. In both cases the dropouts were worse when
> cold.

I want to make sure I understand. These cars had a built-in voltmeter on the
dash, and it was oscillating more than usual? Then you also took a portable
voltmeter under the hood, connected it to the battery terminals, and watched
the voltage at the battery terminals vary?

I have started a site on "Battery & Alternator Tips" and want to include
this or similar.

Doug, I saw your post and agree there is at least a small advantage to going
to the alternator itself for measurements to identify bad brushes. However,
I am trying to devise some quick and dirty checks (if they exist) a
layperson can do to identify likely failed brushes.

Draft: http://home.earthlink.net/~honda.lioness/id13.html

(Not to supplant Tegger. His site is way more comprehensive. I am
anticipating pre-emptively replacing my 91 Civic's brushes in a year or so,
so I'm writing this up as much for that.)

"Elle" <honda.lioness@nospam.earthlink.net> wrote in message
news:mYnHf.13902$rH5.21@newsread2.news.atl.earthli nk.net...
> "Michael Pardee" <michaeltnull@cybertrails.com> wrote
>> "Elle" <honda.lioness@nospam.earthlink.net> wrote
>>> "Michael Pardee" <michaeltnull@cybertrails.com> wrote
>>>> I was lucky that both my cars that had that problem also had
>>>> voltmeters. I noticed the voltmeter in each fluctuating as the brushes
>>>> made contact and then didn't, but the lamps never flickered. (Sometimes
>>>> they wouldn't come on before start-up when the brushes were wearing
>>>> out.) Talk about "idiot lights!"
>>>
>>> Would you say watching the voltage across the battery terminals of an
>>> idling car might also likely pick up bad brushes?
>>>
>> That's how I caught it in both cases. The voltmeter fluctuated sharply
>> between charging and battery voltage. I think the movement of the meter
>> caught my eye as much as actual dash scanning did. At first it was only a
>> couple seconds dropout at a time, worsening to a minute or so good and a
>> minute or so bad within a week. In both cases the dropouts were worse
>> when cold.
>
> I want to make sure I understand. These cars had a built-in voltmeter on
> the dash, and it was oscillating more than usual? Then you also took a
> portable voltmeter under the hood, connected it to the battery terminals,
> and watched the voltage at the battery terminals vary?
>
Exactly right. The meters would show charging voltage (they weren't
calibrated, of course, but we get used to what they read with the engine
running and see what they read before starting) some of the time and
not-charging voltage other times. That got my attention so I checked the
actual voltages at the battery to see if the charging really was
intermittent. Normally the meter in either car would be pretty steady until
I turned the lights or the heater blower on - then it would only drop a bit.
These were big changes.

> I have started a site on "Battery & Alternator Tips" and want to include
> this or similar.
>
> Doug, I saw your post and agree there is at least a small advantage to
> going to the alternator itself for measurements to identify bad brushes.
> However, I am trying to devise some quick and dirty checks (if they exist)
> a layperson can do to identify likely failed brushes.
>
> Draft: http://home.earthlink.net/~honda.lioness/id13.html
>
> (Not to supplant Tegger. His site is way more comprehensive. I am
> anticipating pre-emptively replacing my 91 Civic's brushes in a year or
> so, so I'm writing this up as much for that.)
>
Looks good so far, Elle.

I'm sure if the Volvo and the Nissan didn't have dash voltmeters I wouldn't
have known anything was wrong until the battery gave me real trouble. I
suppose I might have been lucky enough to see the headlights dimming a bit
once in a while, but I dunno.

Mike

"Michael Pardee" <michaeltnull@cybertrails.com> wrote
snip but comments noted
> I'm sure if the Volvo and the Nissan didn't have dash voltmeters I
> wouldn't have known anything was wrong until the battery gave me real
> trouble. I suppose I might have been lucky enough to see the headlights
> dimming a bit once in a while, but I dunno.

Good idea. I agree one might see the headlights dimming (or, really, any
electrical funny business) with voltage dips as serious as that implied by,
say, failing brushes.

Interesting post;

I noticed the exact same problem crop up last week on my 1990 Honda
Civic wagon. The red battery light on the dash would flicker
intermittently ont the highway, and sometimes stay on as long as 5
minutes. The battery is about year old. Now that I am back in the
city, it may flicker a bit and come on for about 10 seconds.

After a voltmeter test, it shows that the alternator is charging the
battery fine when the engine is running, but under full load (radio,
heater, defroster, lights), it is not. Is this something I should be
worried about?

PS,

If the brushes are worn in my alternator, how long would it be until
complete failure?

<theo.chan@gmail.com> wrote
> Interesting post;
>
> I noticed the exact same problem crop up last week on my 1990 Honda
> Civic wagon. The red battery light on the dash would flicker
> intermittently ont the highway, and sometimes stay on as long as 5
> minutes. The battery is about year old. Now that I am back in the
> city, it may flicker a bit and come on for about 10 seconds.
>
> After a voltmeter test, it shows that the alternator is charging the
> battery fine when the engine is running, but under full load (radio,
> heater, defroster, lights), it is not. Is this something I should be
> worried about?

Can you do the five quick and dirty voltage checks at the site
http://home.earthlink.net/~honda.lioness/id13.html and report back?

The voltage is supposed to drop, by design, when you add the loads you list.
The question is how much it is dropping.

Regardless, as you'll see from the commentary at the site above, your
alternator system is highly suspect at this time.

If it's the brushes (and based on posts here, I think that's a very high
likelihood for a car your age), then I would get them replaced as soon as
possible. For one thing, I think the car could leave you stranded any day
now. For another, the condition is going to worsen until the battery does
not charge fully. This does lower the battery's life.

Can you share the battery history of this car, including jumpstarts over the
years? Is the alternator the original, with original brushes?

<theo.chan@gmail.com> wrote in message
news:1139715615.778180.261400@g43g2000cwa.googlegr oups.com...
> PS,
>
> If the brushes are worn in my alternator, how long would it be until
> complete failure?
>
Based on my experiences, I would estimate 1-2 weeks (somewhere around 10
hours operation) from beginning of dropouts to almost never charging. Be
aware the alternator diodes and windings are being overstressed from the
surges to catch up in the meantime, though. I wouldn't recommend putting it
off any longer than really necessary.

Mike

theo.chan@gmail.com wrote in
news:1139715615.778180.261400@g43g2000cwa.googlegr oups.com:

> PS,
>
> If the brushes are worn in my alternator, how long would it be until
> complete failure?
>
>


Now.


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