I have a 1994 John Deere LX178, serial #MOL178A070022 with Kawasaki FD440V 15hp liquid cooled engine. It has an intermittent starting problem. Sometimes it starts and runs normal. Other times (like today) it will not start. Does not turn over, no dash lights come on, no starter click, it's completely dead. If I leave ignition on, and jumper from starter 12v power to solenoid terminal, engine turns over and started once for a few seconds (sounded real weak, maybe running on one cyl?). Battery voltage is at 12.5v. I checked for power at the 2 small coil terminals, they were both less than 5 volts. Any ideas where to begin diagnosing this? I really don't want to start throwing parts at it, they are not cheap.