Getting the books is a good idea but those books won't tell you one of the most important aspects of "keeping it running" (it starts and runs when needed) which is to use or store stabilized fuel and keep the fuel supply fresh. Proper layup of the machine is important if you don't periodically run it up to full operating temperature.

Small engines are remarkably durable if you feed them fresh fuel, check the oil level, change the oil frequently, and keep them from overheat situations.