A1 alternator, need advice

The rubber bushing went to hell, so I jamed a big nut into its place.
This isnt that good of a ground, so I will try the ground strap from
alternator to engine, and chassis. Does an old alternator still put
out 65 amps?

"Nate Nagel" > wrote in message
...
> wrote:
>
> One last thing, is your idiot light working? (i.e. does it come on
> before you start the engine?) having to rev to 3K to energize makes me
> think you may have a "blue wire" fault, although it could also be a
> dying regulator.
>
> good luck
>
> nate
>
> --

What is a "blue wire fault"...on my 01 diesel I have no alternator light with
key in on position before start, and then have to rev to 3000 rpm to get any
voltage from alt.

--
Tony Bad

02 Jetta Wagon
01 Eurovan MV
91 Jetta 1.6 Diesel
86 Jetta
79 Rabbit 1.5 Diesel (semi-retired for now)
Schwinn Continental 10 Speed
Radio Flyer Pedal Car (my daughter made me add this)

"Nate Nagel" > wrote in message
...
> wrote:
>
> One last thing, is your idiot light working? (i.e. does it come on
> before you start the engine?) having to rev to 3K to energize makes me
> think you may have a "blue wire" fault, although it could also be a
> dying regulator.
>
> good luck
>
> nate
>
> --

What is a "blue wire fault"...on my 01 diesel I have no alternator light with
key in on position before start, and then have to rev to 3000 rpm to get any
voltage from alt.

--
Tony Bad

02 Jetta Wagon
01 Eurovan MV
91 Jetta 1.6 Diesel
86 Jetta
79 Rabbit 1.5 Diesel (semi-retired for now)
Schwinn Continental 10 Speed
Radio Flyer Pedal Car (my daughter made me add this)

Bad as*s stereo... you need AMPS and a lot of them! It's not the voltage but
the amps. As an example the new Touareg and Phaeton alternators can put out
over 200 amps with easy and still only have a voltage of 13.8 14.1 volts. So
find yourself the biggest hi AMP alt along with a big cable from the alt to
your battery and then crank up the volume.

> wrote in message
oups.com...
>I have an 82 vw pickup with A/C. It has the stock 65 alternator still
> in it. It has been giving me fits for almost a year now. It quit and
> was rivived with new brushes. I have had to rev it to 3K to get it to
> generate power. I think it is time to replace it. But... I also want
> good power. I run a stereo system with an amp rated at about 500
> watts. This is around 40 amps when running a little under 13V. That
> doesnt sound so bad with a 65 amp alternator. But I can tell you that
> at present, my lights dim terribly when listening to music. Voltage
> drops enough to clip my radio unit. I am getting about 12.5V in warm
> weather. The voltage drops far below 11V with loud music playing. Is
> it possible that my alternator is actually not pushing 65 amps, and
> just needs to be replaced? Should I snag one of those newer 90 amp
> units and try to compress it into the engine compartment? I love
> welding and am not afraid of making brakets. If that is what I should
> do, what model of a VW should I get it from? (for reference at the
> parts store) Oh, and is it possible to make an alternator to put out
> around 15V? That would be great! Thanks guys
>

Bad as*s stereo... you need AMPS and a lot of them! It's not the voltage but
the amps. As an example the new Touareg and Phaeton alternators can put out
over 200 amps with easy and still only have a voltage of 13.8 14.1 volts. So
find yourself the biggest hi AMP alt along with a big cable from the alt to
your battery and then crank up the volume.

> wrote in message
oups.com...
>I have an 82 vw pickup with A/C. It has the stock 65 alternator still
> in it. It has been giving me fits for almost a year now. It quit and
> was rivived with new brushes. I have had to rev it to 3K to get it to
> generate power. I think it is time to replace it. But... I also want
> good power. I run a stereo system with an amp rated at about 500
> watts. This is around 40 amps when running a little under 13V. That
> doesnt sound so bad with a 65 amp alternator. But I can tell you that
> at present, my lights dim terribly when listening to music. Voltage
> drops enough to clip my radio unit. I am getting about 12.5V in warm
> weather. The voltage drops far below 11V with loud music playing. Is
> it possible that my alternator is actually not pushing 65 amps, and
> just needs to be replaced? Should I snag one of those newer 90 amp
> units and try to compress it into the engine compartment? I love
> welding and am not afraid of making brakets. If that is what I should
> do, what model of a VW should I get it from? (for reference at the
> parts store) Oh, and is it possible to make an alternator to put out
> around 15V? That would be great! Thanks guys
>

Tony Bad wrote:

> "Nate Nagel" > wrote in message
> ...
>
wrote:
>>
>>One last thing, is your idiot light working? (i.e. does it come on
>>before you start the engine?) having to rev to 3K to energize makes me
>>think you may have a "blue wire" fault, although it could also be a
>>dying regulator.
>>
>>good luck
>>
>>nate
>>
>>--
>
>
> What is a "blue wire fault"...on my 01 diesel I have no alternator light with
> key in on position before start, and then have to rev to 3000 rpm to get any
> voltage from alt.
>

There is a blue wire that runs from the back of the alternator to the
idiot light in the dash... not only does it make the idiot light work,
but it also provides the 12V (through the idiot light) that the
alternator uses as a reference for system voltage. If the wire is
broken or disconnected, it will work exactly like you are describing.
Had this problem on Michele's Corrado, it ended up being a single wire
connector being unplugged near the "frame" rail behind the driver's side
headlight. (of course I didn't find this out until I'd already popped
out the gauge panel. No matter, I needed to fix the odometer anyway...)

nate

--
replace "fly" with "com" to reply.
http://home.comcast.net/~njnagel

Tony Bad wrote:

> "Nate Nagel" > wrote in message
> ...
>
wrote:
>>
>>One last thing, is your idiot light working? (i.e. does it come on
>>before you start the engine?) having to rev to 3K to energize makes me
>>think you may have a "blue wire" fault, although it could also be a
>>dying regulator.
>>
>>good luck
>>
>>nate
>>
>>--
>
>
> What is a "blue wire fault"...on my 01 diesel I have no alternator light with
> key in on position before start, and then have to rev to 3000 rpm to get any
> voltage from alt.
>

There is a blue wire that runs from the back of the alternator to the
idiot light in the dash... not only does it make the idiot light work,
but it also provides the 12V (through the idiot light) that the
alternator uses as a reference for system voltage. If the wire is
broken or disconnected, it will work exactly like you are describing.
Had this problem on Michele's Corrado, it ended up being a single wire
connector being unplugged near the "frame" rail behind the driver's side
headlight. (of course I didn't find this out until I'd already popped
out the gauge panel. No matter, I needed to fix the odometer anyway...)

nate

--
replace "fly" with "com" to reply.
http://home.comcast.net/~njnagel

wrote:
> Does an old alternator still put out 65 amps?

65 A is the peak rating, the alt can put out this much at high RPM when
it is cold. At lower RPM or after the alternator heats up, the max
output current is less than 65A. I have the spec. for a 65A alternator
(not a VW). The peak when got is only 58A. Cold, it does not reach 65A
until you get to about 2500 RPM (engine speed, 7500 RPM alternator
speed). At idle when cold the alternator can only supply 35A, 25A when
hot.

As the brushes and slip rings wear, you can get increased resistance.
This will lead to reduced field current and lowered output current.

wrote:
> Does an old alternator still put out 65 amps?

65 A is the peak rating, the alt can put out this much at high RPM when
it is cold. At lower RPM or after the alternator heats up, the max
output current is less than 65A. I have the spec. for a 65A alternator
(not a VW). The peak when got is only 58A. Cold, it does not reach 65A
until you get to about 2500 RPM (engine speed, 7500 RPM alternator
speed). At idle when cold the alternator can only supply 35A, 25A when
hot.

As the brushes and slip rings wear, you can get increased resistance.
This will lead to reduced field current and lowered output current.

Tony Bad wrote:

>
> What is a "blue wire fault"...on my 01 diesel I have no alternator light with
> key in on position before start, and then have to rev to 3000 rpm to get any
> voltage from alt.
>

Actually the blue wire is also known as an 'Exciter Wire'.


Yes it supplies 12v to the Alt during start up, and Yes it is wired
through the 'idiot light', it's main function is to provide a source of
electromagnetic power through the coils in the Alt until such time as
it's mechanical motion can start putting out power in the opposite
direction.

One thing to consider; if you don't have the blue wire/light hooked up
the Alt can still 'latch', but you'll need to rev the motor up and long
enough to start generating electricity from the rotation.

In closing I'd like to paraphrase from the good book of the Church of
the Free Electron; being Grounded is Primary, Manage the Hot Side with a
Large Capacity and Cleanliness w/ Good Mechanical Connections are key.


TBerk