My 2002 NH Ls 150 skid steer battery is discharging when left sitting for a week or so. The Battery is new and I suspect something is drawing power when the key is off. There are no lights or other things I can think of that might cause this. I now leave the side panel off and disconnect the battery ground cable when not in use. I have seen a spark on occasion when I go to reconnect the battery cable and I have measured 12v between the loose cable and the battery terminal. Has anyone had this problem or know how to track down the problem. My skid steer has only 350 actual hours on it and is used only for farm work and has not been abused or tampered with.
i would be looking at the ALT. Abad diode can cause this. you need to do more troubleshooting to confirm it.
Yes, I was thinking of the alternator diodes also. I am not sure what checks to make, especially without removing it. Anyone have any ideas on how to proceed?
Those cables have a lot of issues as well. When we ran three LS170s we would replace a couple per year, usually the positive cable sometimes the ground cable.
First option: disconnect the alternator when you let it sit for a week and then see if the battery dies or holds a charge. To do this, first remove the ground cable because the next one is hot. Then remove the big wire going to the back of the alternator, typically a nut. Reconnect the ground. Let sit a week. Disconnect, reconnect, reconnect and see if it starts. Second option: use an ohm-meter or amp-meter to see what the resistance or current is going through the big wire going to the alternator. If using an ohm-meter, remember the diodes will pass current one way, but they shouldn't pass pos through the alternator to ground.