alternator output 12.4V ... battery died ...thoughts?; repairs?

[BC Dave]

battery died ...

electrical dash light stays on; I was thinking it was the regulator (rectifier); but now I think its the alternator; I was going to remove it but didnt have a chance before leaving it for a while ... I did some major wiring repairs last winter when I first got my 180D; I usually disconnect the neg terminal If Im going to leave her for a while; with the tractor running the alternator puts out 12.4 V (at the alternator); it should be about 13.5 to charge the battery; right?

thoughts on testing and have you had an alternator repaired?

 

[winston1]

I think you are running a dynamo. You should test it on wires coming from dynamo to regulator looking for 18 or so ac volts with engine running at least 1800 rpm. If that tests out ok then go to your outlet on the regulator looking for the 13.5 or so dc volts. If your dash lights are staying on something is wired wrong. Your probably have a manual but just in case if you scroll down this tractor support thread you will see a ym180 wiring schematic. http://www.yanmarowners.com/phpbb/viewtopic.php?f=1&t=1452

 

[LD1]

Yep, sounds like an alternator. With it running, you should be ~14v.

And 12.4v isnt even a fully charged battery. A 100% charged battery will read 12.6-12.7V

 

[Car Doc]

Another thing besides the advice givin is always check voltages at the alternator rather than the battery just to do 2 things at once saves chasing your tail needlessly. It may be working and there can be an open in just that one wire in its path to the battery.

 

[BC Dave]

ok-eey

in rethinking; I mistook the starter for the alternator (... well it looked like an alternator ...lol) so I got a 12.4 V reading on the starter leeds; non the less; i should have been getting 12.6 readings; i think i was getting the newly charged reading off the battery ....

so I went ahead and ordered new dynamo alternator (AC) and regulator / rectifier that converts the dynamo charge into DC ... so I was advised by the good people at Hoy tractor ... waiting on parts delivery and I'll give repairs a shoot again next weekend when I have her in forn of me ... ill post the results to help others ...

... another question; who has had wiring problems and what was the cause?

 

[LD1]

ok-eey

so I got a 12.4 V reading on the alternator leeds; non the less; i should have been getting 12.6 readings; i think i was getting the newly charged reading off the battery ....

Still incorrrect. If you only get 12.6v while running somthing is wrong. Running shoud be 13-14v

 

[reb]

Still incorrrect. If you only get 12.6v while running somthing is wrong. Running shoud be 13-14v

That is correct if the battery is fully charged. 12.4 could be correct if the battery is faulty or still charging.

 

[RickB]

That is correct if the battery is fully charged. 12.4 could be correct if the battery is still charging.

Also wrong. 12.4 volts is battery voltage, and a less than fully charged battery at that. A functional charging system will show more than 12.4V when operating.

 

[clemsonfor]

Sounds like your still not sure your battery is good or your charging? I would not have just bought parts to replace ones that may not even be bad.

No offense but you mistook your starter for your alternator/ charging unit? You may have a problem but i'm not sure you know what it is at this point and may be trowing parts at it to "see" if it works. It may fix it, but you may have just replaced a $140 alternator and a $35 regulator or whatever it costs to fix a broken $35 regulator, when the alt may be good in the first place. Or your battery is bad and these parts will ahve no effect.

 

[Reg]

Without knowing the specific tractor and the details of its charging system...
Here is what I see on my truck in the mornings with my dash mounted scan gauge II.
Switch to ON 12.4 to 12.6, but as soon as those (two) batteries suffer a couple of seconds of glow plug current somewhere around 11.8 then back up to 12.4 when the glow plugs time out.
The batteries are in good/fair condition.
Once it starts it goes up to something that is very much temperature dependent.
On a warm day, maybe only 13.4, on a cold and frosty morning 14.1 maybe even 14.2, this is within seconds, i.e. just before I shove it in gear to pull out of the driveway - and I am NOT a driveway idler.
It generally levels out to ~13.8 once the under-hood temperature is stable (1/2 hour or so)

I think these are what you SHOULD see, afterall it is just a lead/acid battery and the terminal volts should be same/similar regardless of the vehicle or charging system.