Alternator issues....

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AuroraGirl

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Work has been making things difficult to do this last week.
I will read through all of these thoughts and suggestions later this week when my project is done and out the door.

I did make it to the junkyard yesterday to find only 3 10/12SI alternators in all of the GM vehicles present. THREE! Crazy talk.

The first one was in a '86 El Camino and I pulled it out and threw it in the cart.
Second was in a 1980 Van and had the wrong mounting orientation.
The last was so very corroded that it did not want to turn.

So I purchased the El Camino one and the extra warranty.
Now I can swap out alternators as much as I want for the next 13 months.

We stopped and had it tested at Autozone.
That guy was a turd and it took him 15 minutes to figure out how to hook it up.
He said it was dead and handed it back.
I do not have much faith in his prognosis.

Tomorrow Max will be putting the alternator in the truck to spin it up and confirm the AZ turds findings.
flash the fielddddddd
 

75gmck25

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If you look up your '79 on the Rockauto site you can find a cheap remanufactured 63 amp alternator for as little as $30, and a brand new Delco 63 amp alternator for $70. Is it really worth it to keep looking for something decent in the junkyard, or would it be easier to just buy one with a full warranty?

Even the Autozone store you visited to get the old alternator tested would sell you a remanufactured 63 amp alternator for as little as $43.

Bruce
 

Ricko1966

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If you look up your '79 on the Rockauto site you can find a cheap remanufactured 63 amp alternator for as little as $30, and a brand new Delco 63 amp alternator for $70. Is it really worth it to keep looking for something decent in the junkyard, or would it be easier to just buy one with a full warranty?

Even the Autozone store you visited to get the old alternator tested would sell you a remanufactured 63 amp alternator for as little as $43.

Bruce

Cheap remains are a crap shoot also.When I worked at O'Reilly I used to test the remans before I'd sell them because so many were junk right out of the box.As a matter of fact last alternator I changed was for a friend who called me. Rick,OReilly tested my alternator and said it was bad I bought a new one(reman) paid my neighbor 50.00 to change it but the light is still on, what's wrong?I ended up driving to his house testing it and removing it because it was bad. Sent back to Oreilly they tested it said yep it's bad.They tested the next one I installed it , problem solved. Now if it had been from Rockauto how would that have played out? My day job,I worked at a mom and pop shop,we didn't sell cheap anything and had almost zero defectives.
 
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Catbox

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If you look up your '79 on the Rockauto site you can find a cheap remanufactured 63 amp alternator for as little as $30, and a brand new Delco 63 amp alternator for $70. Is it really worth it to keep looking for something decent in the junkyard, or would it be easier to just buy one with a full warranty?

Even the Autozone store you visited to get the old alternator tested would sell you a remanufactured 63 amp alternator for as little as $43.

Bruce

I feel ya on the buy a better one solution.

However, with the junkyard approach I can burn them up every day and just keep changing them out.
They don't care if they work or not.

At the rate of finding another decent 10/12SI, we will end up figuring out how to swap to the CS series of alternators as they are all over the place.

Once we get it all sorted and in good shape, we will buy a decent one if the junkyard part craps out again.

Plus I like going to get my exercise at the junkyard.
 

Ricko1966

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I feel ya on the buy a better one solution.

However, with the junkyard approach I can burn them up every day and just keep changing them out.
They don't care if they work or not.

At the rate of finding another decent 10/12SI, we will end up figuring out how to swap to the CS series of alternators as they are all over the place.

Once we get it all sorted and in good shape, we will buy a decent one if the junkyard part craps out again.

Plus I like going to get my exercise at the junkyard.
No not you at all I'd put a good used one on anyday if it worked up until the day the car was junked it's a good one.And they are super easy to test at home.I meant I would not buy a cheap reman especially a cheap reman I couldn't drive back to exchange
 

bucket

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I feel ya on the buy a better one solution.

However, with the junkyard approach I can burn them up every day and just keep changing them out.
They don't care if they work or not.

At the rate of finding another decent 10/12SI, we will end up figuring out how to swap to the CS series of alternators as they are all over the place.

Once we get it all sorted and in good shape, we will buy a decent one if the junkyard part craps out again.

Plus I like going to get my exercise at the junkyard.

You can clock the housing to get the connector and stud in the right location. If you remove the pulley and fan, you can do it without having to get the brushes back in place.

So the 10/12 SI are getting that scarce around there huh? Crazy times I tell ya, lol.
 

Ricko1966

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I meant to tell him that earlier. Forgot. You know there is a hole drilled in the back of the alternator that you can stick a paper clip through, it goes through the brush holder and brushes to hold the brushes in place. Super easy
 

bucket

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I meant to tell him that earlier. Forgot. You know there is a hole drilled in the back of the alternator that you can stick a paper clip through, it goes through the brush holder and brushes to hold the brushes in place. Super easy

Yep, I forgot about that little hole.
 

Catbox

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You can clock the housing to get the connector and stud in the right location. If you remove the pulley and fan, you can do it without having to get the brushes back in place.

So the 10/12 SI are getting that scarce around there huh? Crazy times I tell ya, lol.

I bought the Harbor Freight pulley puller the other day as I headed to the yard.
It's on the way to there.

And yeah, it is crazy how things are currently.
But the yard just flooded and they will soon be working on switching out the inventory.
So hopefully a fresh set of squarebody trucks will show up.
There are currently 4 of them in stock and they are all pretty picked over.

On a side note there is a CS130 in a '91 Caddy that was there.
I went to work removing the belt and got the tensioner loose and pulled the belt.
Then I went on the hunt for a socket or wrench that would fit the 15mm nut.
No dice.
I went to looking for one of the two 15mm wrenches I bought to have in my tool kit.
Both gone.

That kid of mine.
I recently bought a totally new set of tools to carry in the Suburban.
Enough that I can do most things if I would need too.

**** face then uses it as it is complete and easy to access.
Takes my **** and does not put it away.

I can't wait until he has his own children that do this to him....

He is going to pull that alternator this week to install in the truck.
 

bucket

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You don't need a puller. Just use an impact gun to spin the nut off and then the pulley slides right off the shaft. Normally, anyway.
 

Ricko1966

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You don't need a puller. Just use an impact gun to spin the nut off and then the pulley slides right off the shaft. Normally, anyway.
It's been awhile but I don't remember even having to remove the pulley to clock one just take the back off put a paper clip through the brushes rotate it to where you want it and put it back together.
 

bucket

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It's been awhile but I don't remember even having to remove the pulley to clock one just take the back off put a paper clip through the brushes rotate it to where you want it and put it back together.

Yep, you are right. I got in the habit in my younger days, before I knew about the little hole for the brushes. But it seems like every time in recent years that I got one that needed clocked, I also had to swap pullies or replace a bent fan.
 

Bextreme04

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I would check at least two more things here. They aren't just blowing out for no reason.

  1. Make sure you have a proper electric fan circuit that will not cause voltage spikes through the system every time the relay engages/disengages.
  2. Run a voltage drop check on all of your wire runs. This means check the voltage of a wire run while it is energized the same way you checked for resistance. Sometimes you can have continuity on a wire, but not have a good enough connection to push the voltage. If you do a voltage drop test and see anything near or over 1v, you have a problem in that wire run.
 

Catbox

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Well just by dumb luck I was looking at a pic of your truck in another thread. Does this truck have electric fans? What are they off of. The reason I ask is other people on other forumns have had trouble killing alternators by not using the correct fan relays. If you got something you bought as a kit nbd you're probably fine, but some of the junkyard fan motors required a relay with a diode to prevent voltage spikes which were killing alternators. Something to think about. Or do some research.

Well now, I have junior looking into the operation of this gizmo for the truck.
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We do have junkyard Flex A Lite fans on the truck.
I put the relay set up together for it with simple parts.

So no diode to control spikes and such.
But we will soon as a new fan controller comes in the mail soon when we order one.
@Maxwellvis new job at the speed parts house has great discounts on some things.
Not so great or even the same as online for others.
 

Catbox

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flash the fielddddddd
I have the boy looking into this as well.
The alternator from the Bel Air is a known working unit, that is why we stuck it in there.
But it crapped out soon after.

If flashing the field doesn't work, I will just buy a rebuild kit for it and put it back into the car.
Same with the parts house rebuild 94 amp alternator that started this whole thing off.
 

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