battery drain

[jbw]

Hey folks I need some help. I have a JohnDeere 125 Lawn tractor and after several days the battery is too low to start the engine. If I unhook the battery it stays charged. I did the amp test between the battery ground post and the cable and it shows 0.03. I started by unhooking the regulator and the meter showed 0.00 so I got a new one and it still shows a draw on the battery. Should I have 12 volt to the small red wire on the regulator all the time or only with the key on

 

[motoman]

With the key off something is drawing .03 A (30 milliamps) , right? If you have a wiring diagram or schematic start disconnecting any small lamps or switches to see if the current stops.

 

[Nwatson99]

I do not see any reason for the voltage regulator to draw anything with the key off unless you have a clock or something on your IP requiring a little juice.

 

[Mad Mackie]

Hi Troops,
The half wave charging systems found on most small engines will draw power from the battery when the engine is not running. To stop this draw, the charging system is isolated when the keyswitch is in the off position.
Keyswitches are known to be problematic and will wear out in time and the accumulation of crud in the contact area of the keyswitch can leave a path for electricity to flow from the battery positive contact to other normally isolated contacts such as the charging system contact.
Mad Mackie in CT:laughing::biggrin::smile:

 

[motoman]

Try another switch if you can without buying it (fat chance).

 

[jbw]

With the key off something is drawing .03 A (30 milliamps) , right? If you have a wiring diagram or schematic start disconnecting any small lamps or switches to see if the current stops.

Motoman I've unhooked everything including the digital hour meter, a relay next to the starter solenoid, the headlights and the only thing that stops the drain is unpluging the regulator

 

[jbw]

Hi Troops,
The half wave charging systems found on most small engines will draw power from the battery when the engine is not running. To stop this draw, the charging system is isolated when the keyswitch is in the off position.
Keyswitches are known to be problematic and will wear out in time and the accumulation of crud in the contact area of the keyswitch can leave a path for electricity to flow from the battery positive contact to other normally isolated contacts such as the charging system contact.
Mad Mackie in CT:laughing::biggrin::smile:

Mad mackie, I don't have another key switch to try but I'll see if I can test it to see if theres voltage on any wires but one with the key off. The mower has 125 hours on it and I wouldn't think the key switch would be bad but I'm sure it could be

 

[EngineMan]

Pull the wires to the alternator (stator) (yellow maybe) and then see, you may have one going bad. may also be a bad diode if there is one fitted in the wiring.

 

[jbw]

Pull the wires to the alternator (stator) (yellow maybe) and then see, you may have one going bad. may also be a bad diode if there is one fitted in the wiring.

Engineman.....the regulator has a 2 wire plug with yellow wires and one red wire with a round connector. Its my understanding that the round connector is a diode. If I unplug the yellow plug with yellow wires the drain stops

 

[EngineMan]

Engineman.....the regulator has a 2 wire plug with yellow wires and one red wire with a round connector. Its my understanding that the round connector is a diode. If I unplug the yellow plug with yellow wires the drain stops

Then you may well have a bad stator/diode, download this manual and read about how to test it.

https://www.dropbox.com/s/u0yahjk6h95qxwo/01_270962SingleCylinderLHead.pdf