What is internally failing in my alternator and where can I get parts.

Went to the dyno for the stroker motor I put in but that's for another post. After that I drive it for an hour home and not the alternator is bad. It has no charging effect at idle and only makes about 13 volts (confirmed with dmm) at 1500-20 and does not make any more with higher rpm. Battery tested good and alternator /charging system tested bad. It will run with the battery off but if I put any load on it ( headlights, aux fan, heavy stereo usage) it stalls out. I was wondering if there are any people that know the guts of these things as I'm looking to rebuild it. I can't quite afford a new one. Also. Any links to places to buy parts for them. Thanks

Probably better off just going to a junkyard and pulling one. That's what I usually do.

Use the Google, Amazon, or eBay. Your search terms are "Alternator repair kit for Jeep Cherokee, TJ Wrangler Nippondenso Alternator"

If you give them the old alternator at an auto store it can take a decent chunk out of the price of the new one. Wouldnt hurt to call and ask what the cost would be if you need it back on the road quickly. Junkyard alt is another option but you would want to make sure it works. Usually when these fail its just an alternator diode. Repairing your alt is definitely worth it if you have the time however if you are like me you wont have the time ha

This site has parts and repair kits.

http://www.aspwholesale.com/

There are several methods to search for parts and/or repair kit.

If you have the OEM or Denso part number from your alternator you can do a search for parts and repair kits.

Other methods include, make model year vehicle and cross reference other types of part numbers or similar OEM part numbers from other years and part number search for specific alternator parts.

This link has repair kits for Densos. 136 to 160 amps. However they appear to be for large case Denso.

http://www.aspwholesale.com/alternator-rebuild-kits/nippondenso/externally-regulated.html

I would e-mail them and ask if they carry repair kits for small case Densos if that's the type of alternator you have. The site does carry individual parts. If your alternator oem part number search matches, normally it will provide a parts list for the individual parts of your alternator.

Delco repair kits: http://www.aspwholesale.com/alternator-rebuild-kits/delco.html

I haven't used his kits. However, the videos might be helpful.

https://alternatorstarterrebuildkits.com/

The alternators are easy to work on. Lots of material online to walk you through finding the problems too. Look around in your area for an electric motor repair shop, they may be able to get the parts. I use a Mennonite place here.

Here's another video that may be useful and provide some more information about rebuilding Denso alternators.

https://www.youtube.com/watch?v=LqvTHJVQU5g

Before deciding to rebuild, I would pull the alternator and crack open the case. It is not that uncommon for the slip rings to simply wear out, and replacing that is beyond the scope of a simple rebuild kit.

On my Explorer, it would get intermittent. You could hit it with a hammer a couple of times and the rings would work for a while. When I opened it up, the copper that the brushes ride on was simply gone due to wear.

I say this just to prepare you for the possibility. It can be an electrical problem(kit) or a mechanical problem.

old_man said:

Before deciding to rebuild, I would pull the alternator and crack open the case. It is not that uncommon for the slip rings to simply wear out, and replacing that is beyond the scope of a simple rebuild kit.

On my Explorer, it would get intermittent. You could hit it with a hammer a couple of times and the rings would work for a while. When I opened it up, the copper that the brushes ride on was simply gone due to wear.

I say this just to prepare you for the possibility. It can be an electrical problem(kit) or a mechanical problem.

Click to expand...

On the other hand, I have seen brushes stuck in their holders. That can happen when you take them swimming in murky water.

Hypoid said:

On the other hand, I have seen brushes stuck in their holders. That can happen when you take them swimming in murky water.

Click to expand...

Hence the hammer.!!!1