I just installed a new Starter for my 97’ Nissan Pick-up and when I tried to reconnect the battery it started turning over by itself and the battery was arcing. I connected everything on the starter correctly as far as I know and just wanted to know what are the possible reasons that my truck is trying to start itself if I try to reconnect the battery. Did I install the starter wrong? Or is there another issue that I need to address. Also I just got a new battery as well that is larger than the last so I am not sure if that may be part of the problem. Thanks!
You need to go back and check that you didn’t accidentally connect the cable from the battery to the connection between the starter solenoid and the starter. Because if you did, the starter is going operate as soon as you attempt to connect the battery.
You may have over torqued the stud bolt on the starter where you attached the main battery wire. That could cause the head of the bolt inside the solenoid to contact ground and cause a direct short. To verify that is the cause check the resistance between the stud bolt and case of the starter. If the resistance reading is near zero then twist the stud bolt back counter- clockwise slightly and recheck the resistance. It now should show an open connection or infinite resistance. Reconnect the battery lead with less torque on the nut so the stud bolt doesn’t twist.
A larger battery is not the cause of your problem . In my opinion you either have the wires on the starter touching or you got a defective starter . Many starters sold are rebuilt .