strange alternator faliure Corolla '90

Hi

I posted a couple of month ago about my bad alternator. Eventually I
replaced the alternator with
an old one that i bought (app $30) at a scrap yard.

It was the diodes that had failed on the original alternator.

however, the "new" alternator failed after approximatly 1.5 month.
The diodes had failed on this alternator as well.

I went back to the scrapyard and bought another one which (knock on
wood) has worked fine
for the last six months.

My question:

Was it bad luck? Or could it be somekind of hidden fault that burnt
the diodes on the first two alternators?

I thought that diodes were pretty robust and shouldn't fail so easy.

Bad grounding?
Water splash?
To tight belt?
Bad wirering to the voltageregulator?

/Rickard

"kaabdalis" <barrud@gmail.com> wrote in message
news:1162890603.529499.169730@k70g2000cwa.googlegroups.com...[color=blue]
> Hi
>
> I posted a couple of month ago about my bad alternator. Eventually I
> replaced the alternator with
> an old one that i bought (app $30) at a scrap yard.
>
> It was the diodes that had failed on the original alternator.
>
> however, the "new" alternator failed after approximatly 1.5 month.
> The diodes had failed on this alternator as well.
>
> I went back to the scrapyard and bought another one which (knock on
> wood) has worked fine
> for the last six months.
>
> My question:
>
> Was it bad luck? Or could it be somekind of hidden fault that burnt
> the diodes on the first two alternators?
>
> I thought that diodes were pretty robust and shouldn't fail so easy.
>
> Bad grounding?
> Water splash?
> To tight belt?
> Bad wirering to the voltageregulator?
>
> /Rickard
>[/color]

OK, were the alternators NipponDenso, or AC-Delco? Makes a difference.

Charles of Schaumburg

uhhm,
I'm not really sure, but it kind of looks like this
[url]http://image.racepages.com/live/F400089003ND.JPG[/url]

n5hsr skrev:
[color=blue]
> "kaabdalis" <barrud@gmail.com> wrote in message
> news:1162890603.529499.169730@k70g2000cwa.googlegroups.com...[color=green]
> > Hi
> >
> > I posted a couple of month ago about my bad alternator. Eventually I
> > replaced the alternator with
> > an old one that i bought (app $30) at a scrap yard.
> >
> > It was the diodes that had failed on the original alternator.
> >
> > however, the "new" alternator failed after approximatly 1.5 month.
> > The diodes had failed on this alternator as well.
> >
> > I went back to the scrapyard and bought another one which (knock on
> > wood) has worked fine
> > for the last six months.
> >
> > My question:
> >
> > Was it bad luck? Or could it be somekind of hidden fault that burnt
> > the diodes on the first two alternators?
> >
> > I thought that diodes were pretty robust and shouldn't fail so easy.
> >
> > Bad grounding?
> > Water splash?
> > To tight belt?
> > Bad wirering to the voltageregulator?
> >
> > /Rickard
> >[/color]
>
> OK, were the alternators NipponDenso, or AC-Delco? Makes a difference.
>
> Charles of Schaumburg[/color]

"kaabdalis" <barrud@gmail.com> wrote in message
news:1162890603.529499.169730@k70g2000cwa.googlegroups.com...[color=blue]
> Hi
>
> I posted a couple of month ago about my bad alternator. Eventually I
> replaced the alternator with
> an old one that i bought (app $30) at a scrap yard.
>
> It was the diodes that had failed on the original alternator.
>
> however, the "new" alternator failed after approximatly 1.5 month.
> The diodes had failed on this alternator as well.
>
> I went back to the scrapyard and bought another one which (knock on
> wood) has worked fine
> for the last six months.
>
> My question:
>
> Was it bad luck? Or could it be somekind of hidden fault that burnt
> the diodes on the first two alternators?
>
> I thought that diodes were pretty robust and shouldn't fail so easy.
>
> Bad grounding?
> Water splash?
> To tight belt?
> Bad wirering to the voltageregulator?
>
> /Rickard
>[/color]

Toyotas are very consistent, so a problem that appears in one is likely to
appear in another. Conversely, Toyotas do not have a lot of odd,
one-of-a-kind problems.

Any of the things you listed can shorten the life of an alternator or its
components.
--

Ray O
(correct punctuation to reply)

On 7 Nov 2006 01:10:03 -0800, "kaabdalis" <barrud@gmail.com> wrote:
[color=blue]
>My question:
>
>Was it bad luck? Or could it be somekind of hidden fault that burnt
>the diodes on the first two alternators?
>
>I thought that diodes were pretty robust and shouldn't fail so easy.
>
>Bad grounding?
>Water splash?
>To tight belt?
>Bad wirering to the voltageregulator?[/color]

All of the above can be it, but the first thing to check is the
battery. If it's "out of warranty" (48 month battery that's more than
4 years old based on the manufacture date code stamp/sticker) get it
load tested.

Batteries go bad just on time alone. And with weak cells, they'll
overload the alternator by demanding full output constantly.

Too tight a belt usually trashes the ball bearings in the alt.

--<< Bruce >>--

Thanx for your suggestion. I will check out the battery.
Best regards
Rickard

Bruce L. Bergman skrev:
[color=blue]
> On 7 Nov 2006 01:10:03 -0800, "kaabdalis" <barrud@gmail.com> wrote:
>[color=green]
> >My question:
> >
> >Was it bad luck? Or could it be somekind of hidden fault that burnt
> >the diodes on the first two alternators?
> >
> >I thought that diodes were pretty robust and shouldn't fail so easy.
> >
> >Bad grounding?
> >Water splash?
> >To tight belt?
> >Bad wirering to the voltageregulator?[/color]
>
> All of the above can be it, but the first thing to check is the
> battery. If it's "out of warranty" (48 month battery that's more than
> 4 years old based on the manufacture date code stamp/sticker) get it
> load tested.
>
> Batteries go bad just on time alone. And with weak cells, they'll
> overload the alternator by demanding full output constantly.
>
> Too tight a belt usually trashes the ball bearings in the alt.
>
> --<< Bruce >>--[/color]

On mine there were bad (oxidized?) connections both between the alternator
and the battery, and between the battery minus and the ground
(transmission).
But it may well be a bad battery.

Asbjørn


"kaabdalis" <barrud@gmail.com> wrote in message
news:1162970060.041315.280080@e3g2000cwe.googlegroups.com...[color=blue]
>
> Thanx for your suggestion. I will check out the battery.
> Best regards
> Rickard
>
> Bruce L. Bergman skrev:
>[color=green]
>> On 7 Nov 2006 01:10:03 -0800, "kaabdalis" <barrud@gmail.com> wrote:
>>[color=darkred]
>> >My question:
>> >
>> >Was it bad luck? Or could it be somekind of hidden fault that burnt
>> >the diodes on the first two alternators?
>> >
>> >I thought that diodes were pretty robust and shouldn't fail so easy.
>> >
>> >Bad grounding?
>> >Water splash?
>> >To tight belt?
>> >Bad wirering to the voltageregulator?[/color]
>>
>> All of the above can be it, but the first thing to check is the
>> battery. If it's "out of warranty" (48 month battery that's more than
>> 4 years old based on the manufacture date code stamp/sticker) get it
>> load tested.
>>
>> Batteries go bad just on time alone. And with weak cells, they'll
>> overload the alternator by demanding full output constantly.
>>
>> Too tight a belt usually trashes the ball bearings in the alt.
>>
>> --<< Bruce >>--[/color]
>[/color]

Ok, did this problem damage your Alternator?

I did some resistance measurements between the alternator and the
battery.
It seems normal to me.
How do I check if my battery is faulty?

The battery seems ok since I could start and drive the car when the
alternator was broken.
I drove at least 30km with two start without any problem.

/Rickard



Asbjørn skrev:
[color=blue]
> On mine there were bad (oxidized?) connections both between the alternator
> and the battery, and between the battery minus and the ground
> (transmission).
> But it may well be a bad battery.
>
> Asbjørn
>
>
> "kaabdalis" <barrud@gmail.com> wrote in message
> news:1162970060.041315.280080@e3g2000cwe.googlegroups.com...[color=green]
> >
> > Thanx for your suggestion. I will check out the battery.
> > Best regards
> > Rickard
> >
> > Bruce L. Bergman skrev:
> >[color=darkred]
> >> On 7 Nov 2006 01:10:03 -0800, "kaabdalis" <barrud@gmail.com> wrote:
> >>
> >> >My question:
> >> >
> >> >Was it bad luck? Or could it be somekind of hidden fault that burnt
> >> >the diodes on the first two alternators?
> >> >
> >> >I thought that diodes were pretty robust and shouldn't fail so easy.
> >> >
> >> >Bad grounding?
> >> >Water splash?
> >> >To tight belt?
> >> >Bad wirering to the voltageregulator?
> >>
> >> All of the above can be it, but the first thing to check is the
> >> battery. If it's "out of warranty" (48 month battery that's more than
> >> 4 years old based on the manufacture date code stamp/sticker) get it
> >> load tested.
> >>
> >> Batteries go bad just on time alone. And with weak cells, they'll
> >> overload the alternator by demanding full output constantly.
> >>
> >> Too tight a belt usually trashes the ball bearings in the alt.
> >>
> >> --<< Bruce >>--[/color]
> >[/color][/color]

"kaabdalis" <barrud@gmail.com> wrote in message
news:1163018569.605985.294980@m73g2000cwd.googlegroups.com...

Ok, did this problem damage your Alternator?

I did some resistance measurements between the alternator and the
battery.
It seems normal to me.
How do I check if my battery is faulty?

The battery seems ok since I could start and drive the car when the
alternator was broken.
I drove at least 30km with two start without any problem.

/Rickard

*************
You can check if your battery is faulty by performing a load test and
checking the specific gravity of each cell.

Your battery may have been OK before, but driving 30 km with a broken
alternator can ruin the battery unless you have a deep cycle battery. You
may have damaged the battery, which in turn damaged the replacement
alternator.
--

Ray O
(correct punctuation to reply)

Ok, I understand,

How do I set up a load test?


On 8 Nov, 21:57, "Ray O" <rokigawaATtristarassociatesDOTcom> wrote:[color=blue]
> "kaabdalis" <bar...@gmail.com> wrote in messagenews:1163018569.605985.294980@m73g2000cwd.googlegroups.com...
>
> Ok, did this problem damage your Alternator?
>
> I did some resistance measurements between the alternator and the
> battery.
> It seems normal to me.
> How do I check if my battery is faulty?
>
> The battery seems ok since I could start and drive the car when the
> alternator was broken.
> I drove at least 30km with two start without any problem.
>
> /Rickard
>
> *************
> You can check if your battery is faulty by performing a load test and
> checking the specific gravity of each cell.
>
> Your battery may have been OK before, but driving 30 km with a broken
> alternator can ruin the battery unless you have a deep cycle battery. You
> may have damaged the battery, which in turn damaged the replacement
> alternator.
> --
>
> Ray O
> (correct punctuation to reply)[/color]

"kaabdalis" <barrud@gmail.com> wrote in message
news:1163019602.365625.110410@k70g2000cwa.googlegroups.com...[color=blue]
>
> Ok, I understand,
>
> How do I set up a load test?
>[/color]

To load test a battery, you need a device that puts a load on the battery,
cleverly called a load tester. I call them load toasters because they glow
like a toaster's elements when you hook them up to the battery.

Load testers range from $30 to over $1,000 and unless I intended to check a
lot of batteries, I would not invest in one. A lot of auto parts store,
including Sears, will check your battery for free, including load testing.
--

Ray O
(correct punctuation to reply)

[color=blue]
>
> On 8 Nov, 21:57, "Ray O" <rokigawaATtristarassociatesDOTcom> wrote:[color=green]
>> "kaabdalis" <bar...@gmail.com> wrote in
>> messagenews:1163018569.605985.294980@m73g2000cwd.googlegroups.com...
>>
>> Ok, did this problem damage your Alternator?
>>
>> I did some resistance measurements between the alternator and the
>> battery.
>> It seems normal to me.
>> How do I check if my battery is faulty?
>>
>> The battery seems ok since I could start and drive the car when the
>> alternator was broken.
>> I drove at least 30km with two start without any problem.
>>
>> /Rickard
>>
>> *************
>> You can check if your battery is faulty by performing a load test and
>> checking the specific gravity of each cell.
>>
>> Your battery may have been OK before, but driving 30 km with a broken
>> alternator can ruin the battery unless you have a deep cycle battery.
>> You
>> may have damaged the battery, which in turn damaged the replacement
>> alternator.
>> --
>>
>> Ray O
>> (correct punctuation to reply)[/color]
>[/color]

On Wed, 8 Nov 2006 15:37:27 -0600, "Ray O"
<rokigawaATtristarassociatesDOTcom> wrote:[color=blue]
>"kaabdalis" <barrud@gmail.com> wrote in message
>news:1163019602.365625.110410@k70g2000cwa.googlegroups.com...[/color]
[color=blue][color=green]
>> Ok, I understand, How do I set up a load test?[/color]
>
>To load test a battery, you need a device that puts a load on the battery,
>cleverly called a load tester. I call them load toasters because they glow
>like a toaster's elements when you hook them up to the battery.
>
>Load testers range from $30 to over $1,000 and unless I intended to check a
>lot of batteries, I would not invest in one. A lot of auto parts store,
>including Sears, will check your battery for free, including load testing.[/color]

You can buy an inexpensive and perfectly serviceable load tester at
Harbor Freight for $30-ish. Or have it done.

You want to see about 12.6 Volts on the battery with the engine off
and no loads on it - if it can't even manage that, even after you put
a trickle charger on overnight to make sure it's charged, the battery
is toast.

Then you clip the Load Tester cables to the battery posts and turn
on the load bank to put 30 to 60 amps of load on the battery, and
watch the battery output voltage - it shouldn't dip down more than
about a volt, inside the 'Green' area of the tester's voltmeter.

If it drops two to four volts fast, you probably have a bad cell.

--<< Bruce >>--