electrical flow question

[52DAVE]

I know a little about basic electrical circuits but I'm no electrician. There is something I am wondering about. Having bought a cub late last summer I wanted to know if the electrical is right. I do know that the generator is charging. (The tractor keeps running when the ground cable is disconnected.) I have used my multi meter and know that with the switch off and the ground cable disconnected there is no voltage between the post and the cable. There is however a 1.4 mA flow between them. Is this normal or does that mean that mean there is a slight drain on the battery some where when the switch is off.

[staninlowerAL]

Most forum posters would not advise disconnecting the battery with the engine running. Someone will probably weigh in on the reasons why. That being said, you did not say if your cub is a distributor or mag ignition. If it is a mag then disconnecting the battery does not effect the ignition circuit since the mag does not depend on the battery for any electrical power but produces electricity by inductive current within itself. Stan

[tst]

running with the cable offf is a good way to damage the generator, regulator or both

[Eugene]

I have used my multi meter and know that with the switch off and the ground cable disconnected there is no voltage between the post and the cable. There is however a 1.4 mA flow between them. Is this normal or does that mean that mean there is a slight drain on the battery some where when the switch is off.

Idealistically the amp draw should be 0, but .0014 amp draw in next to insignificant.

[52DAVE]

It is a 52 with battery ignition. I don't run it with the ground off. I only did it once to see if the generator was working at all. Last fall just before I put it in the tool shed for the winter I noticed that the amp. gauge barely moved at all whether starting or running. That didn't seem right to me. I would think it should show much more discharge when running the starter. But the needle barely moved at all. It may be that the motor started to fast to show much of any discharge.

[Jim Becker]

Current to power the starter does not go through the ammeter. It will only show current draw from the ignition system (and it will pulse as the points open/close). If you tried to run starter current through the ammeter, the meter would probably melt.

Besides the risk to charging components, disconnecting a battery cable while running risks a battery explosion caused by a spark.

To your original question, old switches (ignition and light) usually have accumulated dirt and metal particles inside that cause some current leakage even when off.

[inairam]

I invested in a battery tester that is this style. I use it all of the time. It tests the charging system and the battery condition. It is simple to use and far safer than disconnecting battery cables for tests.

[52DAVE]

Thanks for the answers. I am planing on working on my cub soon and I want to get every thing done while it's apart. I'll clean every thing as much as I am able as I go.