hi all,, I have a older L275 Kubota ,,I replaced the alternator yesterday took the tractor for a ride also washed it at a pond,,drove it back to the parking spot,,about 2 hours later went to start it and the start would just click...I know the battery is good because I checked it after installing alt...any way I noticed the - battery cable was extremely hot..any body have any idea what is going on? it always cranked fine before is this a sign of a bad starter? your thoughts please...
It sounds like one of your battery cables were hot after the L275 sat for 2 hours. This says that your tractor is drawing current when shut off. My first guess would be worn insulation or a pinched wire on a 12 volt supply cable somewhere, causing a partial short even with the tractor ignition switch off. Or possibly an internal partial short in any device that draws current (including the new alternator).
The two reasons a battery cable would get hot is-
1- Too high a resistance (others here have suggested that it is corroding) but this happens over many years, not after an alternator replacement.
2- Too much current flowing in the battery cable.
Battery terminal connection problems will increase the resistance at the high resistance connection point so that connection will overheat, not the cable (except near the terminal). A different alternator could be leaking current (via an internal partial short) and this increased current would heat a cable and drain your battery quickly when the alternator is not turning.
Considering that your starter is decades old, it is unlikely the starter is causing any current leaking, and even less likely if you were not cranking the engine over when noticing the hot cable. It's most likely you have a cable pinched or its worn insulation is causing leakage to ground. Check all cables you were near when replacing the alternator.
A quick check to verify if you have a partial short on your 12 volt supply cable to the alternator- disconnect this cable at the alternator and also at the battery. Then check the resistance from this cable to ground. It should always be infinity ohms. If that is OK, then you have current draw somewhere else in the system.
I had an L275 for 20 years and loved it. Had zero problems and it was super efficient using very little fuel. You have a great tractor. Hope you get to the bottom of this.