Delco Alternator Rebuild & Upgrade

After I finished my major a couple months ago I could hear a rubbing or bearing noise. It was isolated to either the alternator bearings or the tensioner bearing. So I decided to change both.
Removing the alternator is relatively easy. Just release the tension on the tensioner, remove the belt, three bolts and a couple of wires and it is off. Of course, this job was made more difficult because I put the lower bolt in from the front during the major. That made sense at the time since I did not have to remove the shift cable bracket. So I had to cut the bolt.
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I removed the shaft nut using an impact, which made the job easy. Then removed the pulley, fan, and three torx head bolts. There is also a washer between the bearing face and the fan that will need to be put back in place upon reassembly.
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The front casing was just slid off in this case but others I've been inside took some light tapping to remove. There is also another washer inside the unit on the shaft that must be kept to be reinstalled later. Then the front bearing was removed with a socket and hammer.
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The armature was removed by tapping the rear bearing with a socket and hammer. This removed the armature with the bearing. All the electronics were then removed. To get to them, a plastic cover inside must be removed. I used a small punch from the outside to tap the plastic attachment points to release them. Electronics removal is just a couple of screws after snipping the wires that hold the stator in place.
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This is where I hit a problem. The rear bearing was so messed up that it was pretty much frozen to the shaft. The contact slip rings are so close to the bearing that it made removal without damage a problem. So I purchased a cheap $50.00 rebuilt alternator to use its armature and rear bearing. Following the same procedure, it was torn down.
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I purchased a 220 amp upgrade kit from https://www.aspwholesale.com/alternator-upgrade-kits/delco.html. This includes bearing, electronics, brushes, and a new stator. The electronic parts and brushes were installed. This involves sliding the connector on the brushes into the connector on the part adjacent. There is also another connector that needs to be crimped with pliers.
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There is a pin in the brushes that extends through the rear casing that keeps the brushes in their holder during assembly.
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I pressed in the new front bearing. These come in two sizes. The larger one is used on the 5 rib units and the smaller diameter bearing is used on the three rib units.
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Then the stator was set in place with the wires pushed through the plastic cover. The armature was set in place and the bearing was tapped in until flush. The front cover was installed and the three torx bolts reinstalled.
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THe stator wires were then cut to length and the terminals crimped. There is a small plastic cover that just pushes over these. The washer, fan, pulley and bolt were reinstalled with an impact.
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The alternator was reinstalled. No more noise and it is charging great! I'm hoping it is actually outputting the much higher amperage as advertised but have not tested it.

 

informative post.....thanks for taking the time to post.

 

Great thread. The amp upgrade is good to know.

 

Impressive. Thanks, Larry.

 

Very nice post.

 

Great post. My Delco alternator just failed and I need to do the same. My alternator failed shortly after my cooling fans turned ON. I fried my diodes. I spoke to my local alternator builder and he does not recommend a higher DS130 current output because the idle current is lower than stock.
One thing that peeked my interest is that I could use a modern alternator which has considerably more output current at idle. I would need to modify the top and bottom brackets to use a newer alternator.

 

Thanks. I had some concern about idle charge and the upgrade as well because usually output increase means a reduction in charging at idle. But I'm not getting a light at idle and everything seems fine. I have not tested output with a meter. Maybe I will do that this weekend.

 

Very nice documentation! Thanks for posting. We used to have a place in town that rebuilt starters and alternators....they went out of business and no one around here does this kind of work anymore. Sad.