2440 JD wiring
- Thread starter mcarter
- Start date
Are you sure the battery is okay?
Can you try another for a quick test?
Had a battery that would only show a 13.5 volt and thought charge system was bad. Turned out 1 year old battery had bad cell or something. After replacing alternator parts and regulator/rectifier.
Voltage test at battery terminals (use DC scale) should show 12+ volts at idle and 13.5 to 14.5 at full throttle.
Your amp gauge could be bad. This test will help prove that as well.
Sorry no wire diagrams and I'm not a tractor guy, just standard charging issues no matter what type of machinery.
Here is how I look at these issues;
Alternator produces the voltage, some have everything built in and produce 12 - 14.5 volts dc. Others AC voltage that gets regulated and rectified down to 12-14.5 volts dc by regulators and rectifiers. Amp gauges report how you are doing. Battery use anything above 12 volts to regen itself, rest goes to whatever is running, like lights and radios etc.
Between these is the wires. Good clean connections with not shorts or breaks are a must.
Alternators, regulators, rectifiers, batteries, amp gauges and lastly wires all can go bad.
Given all that the system should work.
Easy, never!
Good luck.
Can you try another for a quick test?
Had a battery that would only show a 13.5 volt and thought charge system was bad. Turned out 1 year old battery had bad cell or something. After replacing alternator parts and regulator/rectifier.
Voltage test at battery terminals (use DC scale) should show 12+ volts at idle and 13.5 to 14.5 at full throttle.
Your amp gauge could be bad. This test will help prove that as well.
Sorry no wire diagrams and I'm not a tractor guy, just standard charging issues no matter what type of machinery.
Here is how I look at these issues;
Alternator produces the voltage, some have everything built in and produce 12 - 14.5 volts dc. Others AC voltage that gets regulated and rectified down to 12-14.5 volts dc by regulators and rectifiers. Amp gauges report how you are doing. Battery use anything above 12 volts to regen itself, rest goes to whatever is running, like lights and radios etc.
Between these is the wires. Good clean connections with not shorts or breaks are a must.
Alternators, regulators, rectifiers, batteries, amp gauges and lastly wires all can go bad.
Given all that the system should work.
Easy, never!
Good luck.
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I'm with Spudhauler on checking the battery. One just went out on the sister's Honda Accord and it had a "green Eye". The cheapo battery tester showed a 100% charge but the volts were too low to crank it. New battery and it cranked right up. Maybe you could even just swap one to see if that could be eliminated. But first, what are the weak battery or no crank symptoms?? Does it click when the key is turned? , do the lights burn brightly?, I had safety switches give me problems. This is one on most seats now . They will cause it to act like it's not in gear or a dead battery. also check the ground ... bordercollie