Case 1845c charge psi in cab buzzer

[knuckleduster271]

Case 1845c charge psi light cab buzzer

Long-time lurker- first time poster: Alternator died, replaced it with a $70 ebay reman- alternator lasted 2 days before it quit charging, I filed a return and ordered a second one- got it put in and immediately after replacement my charge PSI light is on as well as the in cab buzzer. A couple other warning lights are very dimly lit.... Knowing the machine ran fine before the alternator replacement (aside from the charging issue) I unhooked the power lead from the alternator and ran the machine straight off the battery and everything is fine. There are two posts on the voltage regulator, one side is pushing out close to 20 volts while the other side is 14. Putting an alternator in these is not particularly fun and I'm not really happy about having to do it a third time I'm just wondering if anybody else has any insight to something I'm possibly missing? Logically thinking I should probably just purchase alternators elsewhere haha but I don't want to order another one and go through all this again and have it be something simple that I was overlooking. Any help or Insight would be greatly appreciated.

 

[kshansen]

You say on post is putting out 20 volts and one 14 volts which one did you have the"Power lead" connected to?
Any chance of numbers off the alternator and maybe a picture showing the end with the terminals with a pencil pointing to the 20 volt terminal?

 

[knuckleduster271]

You say on post is putting out 20 volts and one 14 volts which one did you have the"Power lead" connected to?
Any chance of numbers off the alternator and maybe a picture showing the end with the terminals with a pencil pointing to the 20 volt terminal?

When i get back in the shop tomorrow ill snap some pics of the first alternator I put on it that I still have to send back.

 

[knuckleduster271]

This is the old alternator-
The power lead was attached here
The second pic is the new alternator
I attached the power lead to the larger post first because it states that it is the battery positive- that is when the charge PSI light illuminated and the buzzer in the cab came on, also a couple of the other warning lights were very very dimly illuminated-
so I then disconnected the alternator from the battery and fired it up again- no buzzer no charge PSI light and the green "systems normal" light is on.
I then attached the power wire to the small post like on the original unit, that is when I stuck a lead to the meter on the larger post and saw that it was pushing out 20 volts.
What is odd is that I ran it while it was hooked to the small post and then the charge PSI light only came on intermittently, the green systems normal light stayed on the whole time and I had no buzzer.
All I can figure is there's a short somewhere in the alternator I'm no electrical Guru by any means so any help would be greatly appreciated

 

[knuckleduster271]

Update:
Had the local case dealer send a technician out to test the charge pressure, it read over 400 psi so he said that was fine. He suspected that the first alternator fried something in the display.
Didnt seem confident that it was a sensor for whatever reason

 

[knuckleduster271]

Does anyone know where the sensor is on this thing?

 

[kshansen]

Have you figured out why this alternator was putting out 20 volts? Did someone sell you a 24 volt alternator by mistake?
Do you have a make and part number for that alternator? I'd like to do some checking to see how it is supposed to be wired.

Also do you have a S/N for the 1845C it would help one try to look up where the sensor is, they made that model for many years with several changes over that time.