Bad alternator?

[jmpSHO]

I bought an alternator at a place that rebuilds them for my 94 ATX. Supposedly it's a 130 amp alternator and I think it is going bad. First I put it in my 94 ATX and I drove about 5 miles and it was idling for about ten min. and when I got back in I noticed my a/c was shutting on and off along with my radio. So I cecked voltage at my battery and it was 9-10 volts and wouldn't change with increasing the throttle. All connections were good. So I took my alternator from my 95 ATX and all is fine with my 94 now. So I bring the alternator back and it test fine. I bring it to Advance and it passed. So I put it in my 95 and check the volt at the battery and it's 14.5 with no load which is the best I ever sew in that car. Now the car idles for about 10 min and I notice the volt drop to about 12 and then 11 and eventually 10. I can reapeatedly do this with the same results. Any thoughts? It's hard to return an alternator if it keeps passing the test.

 

[SHOMON]

Check the voltage at the output lug on the alt. I have seen that ring terminal on the outputwire break or corroded causing low output to the battery. Especially when its been running.

 

[SHOMON]

Where did you have it rebuilt? I know a guy in Hyde Park that is good. I have had good luck and bad luck with his parts. The last time my alt. went though I put a new batt. in at the same time.

 

[jmpSHO]

Check the voltage at the output lug on the alt. I have seen that ring terminal on the outputwire break or corroded causing low output to the battery. Especially when its been running.

I will check it today but the alternator was doing it in two different SHOs.

 

[jmpSHO]

Where did you have it rebuilt? I know a guy in Hyde Park that is good. I have had good luck and bad luck with his parts. The last time my alt. went though I put a new batt. in at the same time.

I bought in Brockton and this is my third alt from him. The other two still work perfectly. Both my SHOs have new Batteries.

 

[ultimatesho]

thats exactly how mine acted in the 92 before it quit......it also passed repeatedly.....finally took a dump on me on my way to the track......just up and died wouldnt jump or nothing.......lost all power and the car died while doing roughly 65 down one of the bypasses

 

[92MTX]

Check the cables at the starter.
Mine came loose, and the A/C wouldn't work.

 

[jmpSHO]

Changed the alternator and everything is fine.

 

[93rev2sev]

good deal.

Note:
Installing a new alternator on a dead battery can damage the alternator.