I am having some strange electrical problems with my 91 le..

91 suby wrote:

> So i have a 91 legacy ls wagon. I am having extreme difficulty finding
> what i beleive is some sort of a short in my charging system. I have a
> pretty decent understanding of alternator and battery operations. I
> have pulled the alternator out of the car and had it tested at the
> local parts stores and voltage was up to par and i also replaced the
> battery so they are both in working order. I took a my voltage meter
> and tested the voltage of the battery when car is off (12.0v) and when
> car is running (12.0 v) with all accesories off. I cant seem to pull
> charge off the alternator. Also my abs,charge,and brake idiots lights
> are on during any operations of the car which now wont start without a
> jump. And sometimes the abs unit continues to run after car is turned
> off. ANd on top of all of that my check engine light is on after car
> gets up to running temp and after i connected the diagnoses wires the
> code reads 35 which is purge valve solenoid failure. So my main
> question is without the continuity of the purge control solenoid valve
> working will that cause my alternator to not be able to charge my
> battery therefore not allowing me to drive without replacing this part.
> I would greatly appreciate any advice or knowledge that anyone could
> share with me... cheers
>
I THINK some of the lights you mention are in the 'exciter' circuit of
the alt. Anyway, try to confirm, when jumpstarting or starting from a
freshly charged battery - all the lights that should be on in the
cluster are on. I doubt the purge valve is part of the charging problem
- not positive.

Carl


--
to reply, change ( .not) to ( .net)
 >> Stay informed about: I am having some strange electrical problems with my 91 le.. 

The purge control solenoid is a separate problem.

Your alternator should produce around 14.7 volts. 12 volts is just too
low. The electrical load on the system is draining the battery because
the alternator's output cannot keep up with demand.

Test the voltage with the engine running and all acc on. Bet that 12
volts drops to even less.
 >> Stay informed about: I am having some strange electrical problems with my 91 le.. 

GOOD! you are on the right track. The reason the light goes *OUT* when you
pull the plug is the regulator is INSIDE your type of Alternator.Since it's
unplugged..the light is now disconnected.Now for the R and R....
First off, Disconnect the battery..your choice of NEG or POS..i prefer the
NEG..no chance of arcing it to ground .
Second, TAKE A PICTURE or draw a diagram of how the belts go, where the
tensioner is ETC ETC...DO NOT rely on memory!.
Third, measure the pulley size in width and diameter! this can be a real
bitch. Example..your alternator has a 2-3/4 pulley and the rebuilt one has a
2" unit. They will look/feel the same but the belt WILL NOT tighten. MEASURE
IT or compare them.Compare the width, same thing..
if too wide it will walk around, too narrow and it will run hot. you MUST
have the correct pulley.The rebuilt shop sees shitloads of alternators all
day. They might not remember yours.
When you "Snug" things down at install time, be careful with the BAT
terminal..usually a 10mm nut."Snug" means snug..not headbolt tight.
You can break it, they are brittle. It will really piss you off and renders
the alternator useless.
While the Alternator is out of the car, place the battery on a charger. 6 to
10 amps is nice. Top it off, your going to need power to get it started.
Taking a brand new alternator and having it charge a dead battery is not a
good idea.They were never designed to bring a dead battery back to life AND
support the electrical demands of the car at the same time.
Price the new unit out at your choice of parts jobbers. Most will price them
out at $200 minus the "Core" value of yours (around $70) for a grand price
of $130 or there about.
A good rebuild shop will hit you for about $60 to $80 USD to rebuild YOUR
original unit. A rebuild takes about 4 hours or so.A "Rebuilt"
Unit will have YOUR original stator windings tested and repainted. You get
your aluminum case pieces back. The regulator is reused if tested good.You
get new front and rear bearing races, new brush holder/brushes.If your diode
assembly tests good, you get them back too.Your Rotor will be tested,
repainted red.Cases will be either sand/glass bead blasted clean and NOT
painted.
Done right..a "Rebuilt" is as good if not better than new!
If they don't have one "in stock" then they will usually rebuild yours in a
few hours. Not uncommon to drop it off in the morning and pick it up that
afternoon.

Good luck!


>
> thanks so very much for this very thorough post
>
> test 1 the voltage is the same
> test 2 voltage the same
> test 3 the voltage is the same
> test 4 i jumped the car and it ran when i unplugged the alternator and
> the voltage remained the same at the battery and battery terminal on
> the alt
>
> so what i conclude is that the alternator /(diodes), hence the blinker
> noise coming from my speakers while i listen to my talk radio on AM,
> have gone bad
> Also while the car is running when i unplug the alt the battery light
> goes off and when i plug it back in the light comes back on i dont know
> what this means but maybe you do .
>
> Thanks again for this much appreciated info
>
 >> Stay informed about: I am having some strange electrical problems with my 91 le.. 

Sorry my "around 14,7 volts" comment so offended you. I'll make an effort
to be more specfic in the future.

John Long (my real name)
 >> Stay informed about: I am having some strange electrical problems with my 91 le.. 

"johninKY" wrote in message

> Sorry my "around 14,7 volts" comment so offended you. I'll make an effort
> to be more specfic in the future.
>
> John Long (my real name)
>
John, I didn't "Call" you on it to be rude. If the guy tried to actually get
14.7 volts..he would never do it.
He would think the regulator was bad, more bucks wasted.
If he actually DID get 14.7 volts, he would waste the battery and shorten
the life of the headlamps.
Devices that have pre-regulation wont be affected, but lamps really don't
care for over-voltage.
Batteries outgas like crazy when you take them above 13.80 Volts.
 >> Stay informed about: I am having some strange electrical problems with my 91 le.. 

johninKY wrote:
> Sorry my "around 14,7 volts" comment so offended you. I'll make an effort
> to be more specfic in the future.
>
> John Long (my real name)
>

Don't worry about it. Buttsnort is a self-appointed battery/alternator
"expert". He's mostly right but he gets rather excited when he sees the
infamous "14.7"

What really matters is that a good alternator will show a fairly rapid
rise on the battery voltage after starting.

I could go head-to-head on his statements and show him a few things but
it's not worth it.
 >> Stay informed about: I am having some strange electrical problems with my 91 le.. 

"nobody >" wrote in message

> johninKY wrote:
>> Sorry my "around 14,7 volts" comment so offended you. I'll make an
>> effort
>> to be more specfic in the future. John Long (my real name)
>>
>
> Don't worry about it. Buttsnort is a self-appointed battery/alternator
> "expert". He's mostly right but he gets rather excited when he sees the
> infamous "14.7"
>
> What really matters is that a good alternator will show a fairly rapid
> rise on the battery voltage after starting.
>
> I could go head-to-head on his statements and show him a few things but
> it's not worth it.

I say "Show" him..if he is wrong you should challenge him!
I read his posts a while back, it makes sense. Where is he wrong?
 >> Stay informed about: I am having some strange electrical problems with my 91 le.. 

Porgy Tirebiter wrote:
> "nobody >" wrote in message
>
>> johninKY wrote:
>>> Sorry my "around 14,7 volts" comment so offended you. I'll make an
>>> effort
>>> to be more specfic in the future. John Long (my real name)
>>>
>> Don't worry about it. Buttsnort is a self-appointed battery/alternator
>> "expert". He's mostly right but he gets rather excited when he sees the
>> infamous "14.7"
>>
>> What really matters is that a good alternator will show a fairly rapid
>> rise on the battery voltage after starting.
>>
>> I could go head-to-head on his statements and show him a few things but
>> it's not worth it.
>
> I say "Show" him..if he is wrong you should challenge him!
> I read his posts a while back, it makes sense. Where is he wrong?
>
>
>

The problem is that the "show hims" are nitpick items that won't matter
either way to the people here. It's the old issue of two answers, both
"technically correct" but conflicting. A lot of them vary because of the
conditions of use:

Fixed vs mobile-
Fixed installations can have much more elaborate charging systems. fixed
installations often have individual "2 volt" cells as well that can be
individually monitored.

Battery type-
Plain "flooded" lead acid, calcium enhanced, flat plate, rolled plate,
gel cell, sealed lead acid, deep cycle glass mat.... and more . Each
type has different "optimal" float and equalize voltages. Some types
must be current limited on charge.

There's more, but I digress.

Those nitpick items are for optimal life and performance. Cells and
batteries (a battery is just a group of connected cells) can last 20
years or more under these "optimal" conditions. Automotive use isn't
optimal. Getting more than 3-4 years is quite good life. I've been able
to get 6 years on one vehicle but less than 3 on another. The 3 year
battery was in a vehicle that hat severe underhood heat issues.
 >> Stay informed about: I am having some strange electrical problems with my 91 le..