Just a stab, but with the tractor on the trailer and chains from the tractor to the trailer AND the trailer connected to a vehicle you were creating a pretty dangerous situation. Those tiny electrons will keep moving and moving AND escaping if you give them a chance.
Here is a copy of my response to your other thread to keep this one going......
"... Damn it, you live way the fuck over there...damn it
Ok, first off, charging a battery on a 2 amp for 24 hours doesn't really mean anything. The battery itself may need to go through a very long deep cycle of reconditioning. Pretty much, there is no charging in this time frame and the battery is getting, for lack of words..a deep tissue massage...yes I said it, so what!
The game changed when you put a brand new battery in there and it still did nothing.
How do the headlights work for proper illumination? Are they very good or poor?
Depending on tooling and funds we will skip the $$$$ section.
Typically the negative cable is from the batt to the frame and the positive is from the batt to the starter.
When you have the time completely disconnect the negative cable from the batt and the frame. Do a really good inspection of both ends. Use a BBQ brush, brillo pad or sand paper and do a very thorough cleaning of all contacts on the cable, frame and batt. Shiny metal is the key! Sometimes the grounding point on the frame may get pretty bad with deep pitted corrosion. Clean it up REAL good and if the metal is no not smooth than do the best you can and level it for good contact.
Moving to the Positive cable, also disconnect both ends and check for condition. Holding the cable in one hand, pull the crimped connectors with your other hand. See if they move separate of the cable and see if you can pull it off the cable. Neither should be able to happen.
A really good charged battery can push amps through those type of conditions BUT the small amount of amperage required to re-charge the batt will never make it. ...."
Dusty