I went to start my old dozer the other day and the battery was so low that the starter could barely turn the Diesel engine over a couple of revs. I put the battery charger on overnight and tried the next day. I push the starter button and nothing happens. I have tried a different battery and same results. When I push the start button, I see that the amp meter shows a -13 amps. I am thinking that since the amp meter registers a -13, that the switch must be good?? I hear no starter solenoid click when I pressed the start button, so I have replaced the solenoid. That did not help. When I turn the key counter clockwise, I can hear the manifold heater relay click. There is a second relay that looks just like the manifold heater relay. (not sure what that relay is for) I hear no click from that relay in start or heat mode. Any Ideas? Thanks