Working on a case 450 skid steer. The machine operates perfect for weeks at a time. Then all the sudden the park brake sets it’s self. You can turn it off go about 10’ or sometimes run for 30 mins and it does it again. Each time I have noticed the battery is low. Alternator is charging. If I put battery charger on it and charge up battery it will run for days. I can not find anything that is draining the battery while unit is off. Problem seems to be while machine is running. Any ideals Thanks Bud
How old is the Battery? Sometimes the battery plates work loose within the case and don't provide the correct voltage. Did you try replacing the battery with a new one and see if the problem persists?
Yes first time I had this problem I replaced battery with a new Case battery. I think the problem is voltage is getting low and safety switches are closing. But for the life of me I can’t figure out why.
If it sits for a week and then still starts, then the battery is fine. Put a volt meter in there so you can see what the actual voltage is while running. It may charge at 14V when it's cold and you check it, you need a multimeter in the cab so you can see what it does when it locks up. It's not unusual for an alternator to work when cold, then drop off as it warms up, and repeat for a while. Another possibility is a short that's not blowing a fuse, like the alternator big power line or a battery cable.
One thing I just found is that when the disconnect switch is turned off. You can put a test light lead on a bolt. Touch it to positive battery post and nothing. Touch it to negative post or cable and light shows 12.4 volts of ground. Why would it show ground when light itself is grounded? Am I forgetting something?
Is the disconnect on your ground cable?
Yes it is.