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Discussion Starter · #1 ·
Just out of curiosity, what exactly is the charge meter (ammmeter/ampmeter/etc) on the tractor supposed to do? I know it shows if the charging system is working correctly, but how does it show this? In other words, if it's working correctly, what should the needle do at startup and while running? Stay still, bounce around, wiggle between two points, etc? I only ask because I was watching cub videos on YouTube (hey...I have to do something while the baby sleeps, right?) and I saw a video where the needle is bouncing all over the place while the engine is running. On mine, it moves a little, but not much. I have it partially apart right now, so if the meter is bad (or anything else is bad for that matter) I'd rather change/fix it now instead of having to take everything all apart again.
 

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If it is charging the needle will show above a certain point (13 volts?) and if you rev up the engine it may move a little as well but be cut off by the voltage regulator (14ish volts). If it is not charging then it will register below battery voltage (12voltish). If it is bouncing around I would say the gauge is probably either bad or lower quality, and is doing that because of vibration.

Others know WAY more about this than I do, but these are my experience's.
 

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Ammeter doesn't show voltage, it shows amperage, more importantly, direction of the flow of. Toward the + and your charging the battery, toward the - and your discharging the battery, centered means the alternator (or it's tractor kin, starter I think it is in most cases) is putting out about as much amperage as your using. Don't worry about start up, unless it's not starting, then you can look at the gauge, going toward - is normal, going all the way to - could mean the battery is dead. Running it should be on the + side right after start up and then head toward center and slightly to +, thats a good place to be, all is well. If running it's toward - then try turning off some power drain you don't really need, like the lights or something.

As to the movement, yours sounds right, if it's bouncing around then it should probably be replaced.
 

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The voice of reason !
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Just out of curiosity, what exactly is the charge meter (ammmeter/ampmeter/etc) on the tractor supposed to do? I know it shows if the charging system is working correctly, but how does it show this? In other words, if it's working correctly, what should the needle do at startup and while running? Stay still, bounce around, wiggle between two points, etc? I only ask because I was watching cub videos on YouTube (hey...I have to do something while the baby sleeps, right?) and I saw a video where the needle is bouncing all over the place while the engine is running. On mine, it moves a little, but not much. I have it partially apart right now, so if the meter is bad (or anything else is bad for that matter) I'd rather change/fix it now instead of having to take everything all apart again.
The way it works is simple electricity flows in one direction when it's charging and the other when discharging the ammeter picks up this flow and shows it by moving the needle.

Now on cheaper tractors like mine the meter has a hook on the back that you route one of the wires thru ( or in mine several wraps of wire), the meter picks up the current and reads 0 when off and when I start it it shows slightly below this when cranking it once it starts the alternator starts putting back the power used to start it and shows + 5 amps.

While running it charges the battery and the meter drops to about + 1 amp as the battery gets closer to full capacity or charge.

the longer it runs the more it tops off the battery.

The bouncing needle could be a number of things bad charging system (which I doubt), weak battery (maybe), or like mine it's just a cheap gauge and may be helped by putting a couple of more turns of wire on the back if you have enough slack in the harness.

A few questions :

#1 Did it start and keep the battery charged when it was up and running ?

#2 How old is the battery and have you maintained it like you should ?

#3 Has the gauge always given strange readings (i.e. a bouncing needle) ?

#4 If you have any doubts about #1 & #3 you can check them with a separate meter.

Hope this helps
 

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It depends on the meter how much it will move. If its an IH stewart warner meter it should go way up after startup and then move toward the 3/4 mark. If its a replacement it depends on the rating of the meter on how far it may move. If it one for a car that reads at 50 amps it should barely move. The kohler charging system puts about 15 amps.
 

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So little time.....
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Discussion Starter · #7 ·
It depends on the meter how much it will move. If its an IH stewart warner meter it should go way up after startup and then move toward the 3/4 mark. If its a replacement it depends on the rating of the meter on how far it may move. If it one for a car that reads at 50 amps it should barely move. The kohler charging system puts about 15 amps.

Hmmmm. Now that you say that, I have to double check what it does. When I get it put back together later in the week and have a chance to start her up, I'll report back. Maybe I'll even try out my fancy schmancy new video camera that we just got (for taking videos of the baby, of course)!
 

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oops, missed the whole amps part of ammeter :fing20:
 
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