New 3 wire delco alternator problems
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URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=188456
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Topic: New 3 wire delco alternator problems
Posted By: DIESEL
Subject: New 3 wire delco alternator problems
Date Posted: 25 May 2022 at 9:36pm
| I've got a new 3 wire delco alternator from Napa on my 7050 that was over charging the other day, and it fried my stereo and pegged the temp gauge. Anyone else have problems with these new alternators and is there a fix, buying a new baler and don't want to fry the monitor. TIA |
Replies:
Posted By: jaybmiller
Date Posted: 26 May 2022 at 6:18am
|
hmm.. any chance the alt was for a gas and not diesel engine ? I'm thinking the wiring might be different and 'something' caused the alt to go 'whacky'. overcharging (amps) could be the battery has a bad cell and alt 'sees' a low battery,so it keeps charging it. 'fried' seems to imply overvoltage... be interesting to hear what others think... ------------- 3 D-14s,A-C forklift, B-112 Kubota BX23S lil' TOOT( The Other Orange Tractor) Never burn your bridges, unless you can walk on water |
Posted By: steve(ill)
Date Posted: 26 May 2022 at 9:16am
|
hard to screw up a 3 wire alternator with EXTERNAL problems... The alternator has an INTERNAL regulator and is suppose to be self sufficient.... Sometimes you just get a BAD alternator... Sometimes, by mistake, you short out a couple wires or ground something and it blows out the regulator.. ------------- Like them all, but love the "B"s. |
Posted By: DIESEL
Date Posted: 26 May 2022 at 1:00pm
| My wiring looks good, I suspect the regulator burned up, just got this one because the last one dropped the tach signal at 30 days old. I was measuring 16 volts at the alternator, at 1500 rpm. |
Posted By: Steve in NJ
Date Posted: 27 May 2022 at 7:23am
|
The first thing I would check is the Battery as Jay mentioned. An internally shorted Battery could load up that Alternator big time and put it in a high overcharge state, enough to start taking out components in the system. If the Battery draws tests okay, the next thing I would go to is the Ammeter (if equipped) and see if that shorted out back-feeding the Alternator and blowing the trio or VR out. Next would be a complete inspection of the wiring system for pinched wire(s). If you lost the tach prior to your new Alternator cookin', you have a problem in the system somewhere putting a load on the Alternator in a major way. You need to find the problem before installing another Alternator.... Steve@B&B ------------- 39'RC, 43'WC, 48'B, 49'G, 50'WF, 65 Big 10, 67'B-110, 75'716H, 2-620's, & a Motorhead wife |
Posted By: Les Kerf
Date Posted: 27 May 2022 at 10:45am
|
Testing the battery is always a good troubleshooting policy. However, a good alternator/regulator combination attempting to charge a battery in which a cell is shorted will simply increase the field current and thus increase the charging current, but the voltage will NOT increase unless the regulator is bad. If the short circuit load increases beyond the ability of the alternator to provide current, then the output voltage will decrease, regardless of the voltage regulator's attempt to push more field current into the system. This higher amperage generates lots of heat which can then certainly damage the alternator and also further damage the battery. Excessively high voltage is a regulator problem and can definitely fry stuff that doesn't like higher than expected voltage. It is possible (but unlikely in my experience) that a shorted battery may be the root cause of the regulator being damaged. As mentioned above, test the battery, then replace the alternator. |
Posted By: DIESEL
Date Posted: 27 May 2022 at 2:24pm
| I can test the batteries, but they are only a year and a half old. |
Posted By: Les Kerf
Date Posted: 27 May 2022 at 2:53pm
The symptoms you described above do not indicate battery trouble to me but it never hurts to check |
DIESEL wrote: