dusting901

SKIP TO BOTTOM FOR SUMMARYfor those who dont like to read

my tpi 400 in my 74 caprice will not charge.

about a month ago im driving to my buddys house and bam indicator light comes on a month after i replaced my original alt with a high output 3 wire 10si. so when i get back to the house no prob i test at the back of the alt i get 11.8 or 11.9 volts which is battery voltage. damn

i had a brand new duralast alternator from autozone lying around so i swapped them. still no good, battery voltage. i tested all the wiring and it comes out perfect voltage readings in all the right places. just in case i take a 10g wire run it from battery pos+ to the battery post on the alt, 12g from battery post on alt to sense spade on regulator, and 12g from pos+ on battery to the field spade or the indicator light spade on regulator with a lamp in between. perfect ground so this IS NOT a wiring problem STOCK WIRING IS OUT OF THE PICTURE.

i figure i must by chance have 2 bad new alternators lightning struck me twice somehow. i get a replacement because the autozone alt is under warranty. still no good. my buddy lends me a brand new battery it idles until the voltage drops and that same day is when i find out my first battery had a short and is trash. get that replaced under warranty along with a 4th alternator and figure somehow this shorted battery is eating any alternator it touches.

4th new remanufactured alternator and 3rd brand new battery and still no good just battery volts at the back of the alternator. OH YEAH every alternator tested good at autozone but they test without load.

SUMMARY for those who dont like to read

my wiring is perfect all the right volts in all the right places(10si wiring is extremely basic), this is my 4th brand new remanufactured 10si alternator, brand new battery, alternator tests good at autozone NO LOAD TEST and still NO ****IN CHARGE.

dusting901

the sense wire also had filled with resistance and snapped off but it has been replaced ever since the second alternator

resistance in the sense wire would cause a overcharging situation

jkrustchinsky

your 3 wire alternator requires power to turn it on, is it getting power

dusting901

if you read the second paragraph it sais its getting battery voltage with a indicator light in between

ASE doc

You've tried three alternators since your first alt stopped charging. It is possible that a shorted battery took out the alt but not likely, and that doesn't explain the new one not working. So, if we assume that you now have a good battery and alternator, that leaves only wiring. Are you testing voltages from engine ground?

gwarren007

iTrader: (1)

Please take a picture of the back of the alternator and post it.

dusting901

The voltage from alternator body to - is .06 so its good and i took a steel brush to every ground connection so im pretty sure im good on the ground.

And like i said the stock wiring is out of the picture completely so i have much confidence its not a wiring problem. One thing i did notice weird is the pulley burns my fingers to the touch. No squeal but i know the gm v belt will just slip and not squeal sometimes causing the pulley to heat up. The only thing is i got a new belt, tried at multiple tensions and it still heats up to the point where i burn my fingers.

I feel like this prob is way too basic to be holding me up like it is. I dont find it likely that i got 4 bad alternators but thats looking like the only possibility. They are remanufatured.

Ill post a few pictures in about 20 minutes

dusting901

the three pics.

before i had a 10g audio wire going from battery pos+ to the + post on the alternator. now as you can see i got the original wire that wire is perfect though. thats the only reason i switched it back i already checked the fusible link and the wire is live with battery voltage 24/7

dusting901

dont quit on me now guys

formula 89

try a single wire alternator,cuts out alot of the guess work

8t2 z-chev

the pulley getting burning hot is very suspect-have
you been using the same pulley on all the alternators
or did each one come with a different pulley?
with the direct connections you tried it almost has to
work as long as the pulley is turning fast enough...
I have had shorted batteries before and the alternator
handled it fine-just boiled dry the remaining"good"
battery cells from the overcharge
Really sounds like a belt slippage problem.

ASE doc

There seems to be a specific method of connecting the #1 and #2 terminals for activation and control of the indicator light. Changing the adjusting resistor changes the units voltage setting. I don't know if simply connecting terminal #1 to batt + is going to produce the same results as the factory wiring did.

I found some good information by searching for 10SI on google. I haven't played with these old units for a while myself, and yes it does seem like a simple problem. Find a factory diagram using this regulator and look for differences in the factory wiring, including the adjusting resistor, and what you have.

What may have changed from your original install when the unit worked?

dusting901

Z chev i have been using different pulleys on each alt. They were all generally the same except the very first 100 amp was a chrome pulley. I still got that pulley so i think im gonna swap that today.

ASE doc what is this adjusting voltage setting you speak of??? The stock wiring for terminal 1 (got the dash apart) goes from battery to ign switch that gets 12 in on positon an then to the dash light and then to terminal 1. In one of the pictures its kinda hard to see but i got terminal 1 going to a light and then to pos+ battery. This is exacly how its supposed to be wired to my knowledge.

And last but not least formula 89 i would go to a 1 wire regulator and im seriously considering but i want to be 100 percent positive that will fix it and not only that but i kinda like the light call me an idiot but an idiot light is alot more noticable than a guage.

dusting901

Anyone that has a 10si alternator and a v belt if you could run your car for 3 minutes and touch the pulley and post the results. Did it burn you was it cold. Usually after 3 minutes my pulley is pretty hot. I want to know how normal this is.

ASE doc

The hot pulley is odd. I assume you're adjusting the belt to 1/4 inch deflection. This might be caused by an electrical fault in the alternator causing high current draw.

The adjusting resistor is a shunt between terminal #1 and #2. It looks like standard is 40ohm for 13.8v output. Try the google search. You'll find the same articles I did.

dusting901

Ignition switch. It gets fried in an over charging situation and creates a drain. I had a overcharging situation and i got a drain.

If this doesnt fix it im gonna burn the car down and sell it for 200