Pelican Parts Forums - Alternator for my 1983 S

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- - Alternator for my 1983 S (http://forums.pelicanparts.com/showthread.php?t=624299)

HI Neil,

My Wal-Mart Battery is a 850cca. Not sure how to test what your asking. I just threw it on my trickle charger at 2amps. How long should I keep it on there before testing?

Also, is 13.7 Volts off the front post high enough? This is what I got when I disconnected my Battery.

Most stores won't do a warranty related battery test unless its charged, so yeah, charge it first or plan on shopping for an hour or so while it charges there.

If you are measuring 13v+ at the battery, I suspect the alternator is fine, you don't get volts unless there is the current to make them happen. If the battery is fully charged and the voltage is barely 13v, it could be weak and needs a load test to be sure, but turning on the heater fan to full and headlights to high make a fair load.

Testing without the battery connected isn't a good idea, too much fluctuation if you don't have much load, and not sure it tells that much without something "smarter" than a volt meter.

Quote:

Originally Posted by Danglerb (Post 6207301)

Hi Mike,

I am using a Multimeter (pictured) when I am not driving the car. Just measured 12.7v on the Autozone Battery after an all night trickle charge. I'll re-measure in an hour or so to see if there is a change.

I have the Wal-Mart Battery on the trickle now.

Battery voltage goes up a bit when fully charged, like the foam on a beer it means nothing, put the headlights on for a couple minutes, then off and read the voltage again. 12.7v sounds like a good full charge to me.

Quote:

Originally Posted by MPDano (Post 6206648)

NP, Leo - keep it on the trickle until the charge drops to below 1 amp, and the voltage reads 12.6 when disconnected from the charger. Note, a trickle charge may give false results - better to put on a high amp charger ( 20 or 50 A) and test.

I ended up getting a Beck/Arnley Remanufactured Alternator - 90 Amps from Advance Auto Online. They were the ONLY ones I could find a Reman from. Anyways, they ended sending me 2 by mistake while I will return one. They came with a test sheet each and one actually tested better, so needless to say I used the better one. Here are the sheets. I also just put in the Alt tonight and did a test run, I was able to have headlights and the AC at the same time without issue. I do think my Wal Mart Battery is faulty as I will test again with my Autozone one that is in my Euro at the moment. I am trying to use up all the gas so I can pull the in-tank pump and inspect.

http://forums.pelicanparts.com/uploa...1315367103.jpg

http://forums.pelicanparts.com/uploa...1315367108.jpg

Did you use a coupon? Advanced Auto parts has some killer coupons from time to time, worth a google when buying. If you need to bump the total up, they carry Griots detail stuff.

Quote:

Originally Posted by Danglerb (Post 6240555)

Did you use a coupon? Advanced Auto parts has some killer coupons from time to time, worth a google when buying. If you need to bump the total up, they carry Griots detail stuff.

Yup, 15% off plus free shipping plus a $50 coupon to spend at their shop.

Ok, pulled my Alterenator out again today to put a new Huco Voltage Regulator that I bought from Roger. I trust him so no question that this part would not be the issue if I wasn't getting the voltage I need after the install.

http://forums.pelicanparts.com/uploa...1316655849.jpg

http://forums.pelicanparts.com/uploa...1316655853.jpg

Here is the Remanufactured Alternator from Advance Auto. I already suspected the Voltage Regulator even before I put the Alt on as it didn't look new. I also pulled the Part Number off the old Voltage Regulator and it came back as one from China. Piece of Craaap! http://www.alibaba.com/product-gs/452389069/IP2700_12V_autmobile_electrical_voltage_regulator. html

http://forums.pelicanparts.com/uploa...1316655857.jpg

http://forums.pelicanparts.com/uploa...1316655861.jpg

I had to use an Impact Screwdriver to get the two screws off since they were on so tight. Worked like a charm.

http://forums.pelicanparts.com/uploa...1316655865.jpg

http://forums.pelicanparts.com/uploa...1316655869.jpg

Even this didn't look right as soon as I got the Regulator off, here is the before.

http://forums.pelicanparts.com/uploa...1316655873.jpg

Here is the after, I used a very very fine sandpaper to remove the black marks

http://forums.pelicanparts.com/uploa...1316655881.jpg

I used Blue Locktite on the supplied screws to make sure they didn't back out on me.

http://forums.pelicanparts.com/uploa...1316655886.jpg

NOTE I know this is an old thread and it seems like some tail chasing might have been happening.

Here are a few bits of info for a happy charging system in your 928.

SO incase anyone travels here for info dont use the pod gauge for your diagnosis.

Take a reading from the hot post .

NOTE the dash gauge is only a trend item and it can be adjusted by taking it apart,
but first clean the grounds under the dash and replace the instruments fuse,
the gauge reading may come back.

NOTE the alternator output is also RPM dependent,
if your testing at idle you might be reading battery voltage.

Try turning the idle up a bit to say 900 RPM.

NOTE by 1500 RPM you should be getting A HEALTY 14.2 v CHARGE.
make all of your tests at this RPM for more accurate readings.

NOTE for all years the starting relays can be damaged by trying to start the engine with a low battery,
this makes the relays have a weaker closing force, this then causes the contacts to arc,
and after many cycles the contacts may not pass voltage.
Most relays can have the contacts cleaned to restore function.

NOTE if the system is charging at 14.6 v or higher, then the regulator should be changed,
this will boil the battery.

If the system is charging at 13.4 or less then one of the diodes has probably failed,

NOTE an erratic charging indication could be caused by worn brushes or worn slip rings or a damaged rectifier.

NOTE dont put a battery booster on the system thats over 12 amps,
this is how you can damage the diodes or the regulator.

The Ideal charging is done with a 6 amp charger, usually for a about 4 to 6 hours.

NOTE dont disconnect the ground strap with the engine running,
as this is how you can smoke the diodes or the regulator ,
the battery needs to be in the system to absorb spikes in the charging output.

NOTE a trickle charger is not a battery charger .
OK for a week or two .
Otherwise disconnect the battery.

NOTE you should charge the battery every 3 months,
and if the car is sitting disconnect the battery instead of leaving connected,
this will keep the battery isolated and ready for use.

Also this will remove the charging voltage that passes through the engine,
and can corrode the head gasket surfaces..

Ideally dont jump another car with the 928,
things get expensive if you make a mistake or cause large electron spikes.