We ran our backhoe the other nite in a snow storm and after about 3 hrs all the lights dimmed and it was losing juice... the automatic clutch on bucket control stopped working, basically the batteries were drained... i replaced alternator like a month ago and we checked it at alternator and battery and it was producing like a hair over 14v? is that not enough to keep the machine charged running all the lights, beacon, clutch etc... both batteries are new/newer within last 6 months as well? when i turn on all the lights etc i see on the guage that the volts go down and its borderline "charging". thoughts?
A hair over 14 volts is good. If your battery or batteries are good (no shorted cells) 14 volts is a good charge from the alternator. Anywhere between 14.0 and 14.6 V is good. My JD 310D does not have an automatic clutch on bucket control and I don't even know what that is but I have 4 55 watt head lights and 2 55 watt rear lights, running lights, flashing lights, a strobe beacon, wipers, and a heater motor running on high to defrost the windows and my 63 watt alternator keeps up just fine. Your alternator may have quit. My last alternator from UAP lasted about 50 hrs. and decided to quit. The warranty supplied another but I wander how it will do. I have double v-belts that whip. I wander if that is not the reason for premature alternator failure. I am installing an idler or a nylon slide to stop the whipping this weekend.
I sounds to me like you have too small an alternator, lights at 12 watts @12 volts =1amp, 330w /12= 27amps, two batteries @200amps charging @50% 200amps x 2 =400/2 =200,now add a heating motor,beacon say give it 10amps so total amps required are 27+200+10 = 237 amps at full load...............
i am thinking the alternator is too small also... figure (4) work lights, (4) emerg flashers, heater, instrument lights, beacon, and that auto clutch (basically its a button you engage and it stops the machine dead in its tracks and you can hit the throttle pedal and raise and lower the bucket with faster speeds, then you click off the button and the machine trans starts again... plus if we turn everything off after it drains the batteries, after 2 hrs of so, the batteries are fully charged again?? i think i should buy a bigger alt?
update: i looked at the receipt for the alternator i bought a month ago.. only 65 amps! def too small right?
You need a bigger alternator to carry that load.
OK, you call it an automatic clutch, I call it a clutch disconnect switch. I have one on the loader control and another on the shift lever. About your alternator. I am not the one that can calculate how large your alternator needs to be. Stock has it all calculated and is probably absolutely correct but my 310D has all the lights, heater motor, clutch disconnect switch, 4 way flashing lights, a beacon and every other electrical draw you have and the 63 amp alternator was installed at the John Deere factory and it worked for 8500 hrs. How? I have tested my batteries from time to time after the machine has been sitting for days and the batteries read 12.9 volts. Is your alternator belt tight or is your belt worn narrow enough that the belt in bottoming out in the pulley?