Old, is it a Komatsu excavator? Sometimes when the alternator goes/gets bad, it will put voltage to its "R" terminal, making it think it is running, thereby not letting it crank. Causes funny cranking problems SOMETIMES. I believe it should crank even if only at 12 volts even. Check both batteries separately, then hook them up together, and verify you DO have 24V. I had one that would crank slow, (PC300), check each battery separate and they were each over 12V and both load tested ok. Hook them together, and could only get 16 volts. Not sure what went wrong inside that one battery as no matter how I checked they came out good separately. I ended taking a different battery up to it and hooking the originals up to that new one. The one that gave me 24 volts with the new battery was kept, the bad have me 16V again, replaced it. Anyway, remove the wire on the "R" terminal of the alternator, see if it then will crank. If so, its about a 99% chance your alternator is junk. There should be no voltage to the "R" terminal or wire going to it until it is running. There is I believe a "safety start" or whatever it is called down near the back of the engine? Bunch of junk that all has to work together/see the right things to start.
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Today's Featured Article - Timing Your Magneto Ignition Tractor - by Chris Pratt. If you have done major engine work or restored your tractor, chances are you removed the magneto and spark plug wires and eventually reached the point where you had to put it all back together and make it run. On our first cosmetic restoration, not having a manual, we carefully marked the wires, taped the magneto in the position it came off, and were careful not to turn the engine over while we had these components off. We thought we could get by with this since the engine ran perfectly and would not need any internal work. After the cleanup and painting was done, we began reassembly and finally came to t
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