Hi folks, I have a Kobelco K905 LC-2 excavator. The machine has been sitting for 2-3 years but started right up. I just bought 2 new batteries and after about 1 week they were dead. I recently replaced the battery relay and that is working fine. The batteries were fully charged and the connections are tight. How can I check to see if the alternator is charging and how many volts. Does anyone have a wiring diagram of the alternator so I can make sure all the required wires are hooked up? Thanks.
Take a meter and record the voltage at the battery before you start the engine. If the voltage continues to drop while running the engine with no fluctuations on the meter your alternator is not producing electricity. If you notice the meter recording fluctuations in voltage it most likely means the voltage regulator is shot. Your alternator should put out around 14.4 volts depending on the factory specs. Obviously you'll need to make sure the batteries are fully recharged before you do this...
Did it run in that one week or did they drain while sitting? Most older equipment is good about shutting everything off, so the alternator may be leaking (diodes), draining your battery over time. After you check that it's charging, disconnect the ground cable from the battery and see if they hold a charge.
On older equipment you can remove the neg cable to check the altenator. just be safe about it
Can I test this way with a 24 volt system?
26-29 volts is what you're looking for, just double anything 12V related.