I got a riding mower from my aunt, I was the last one to use it last year and it had trouble starting but when it started it stayed running but now it won't. It has a 15 hp ohv briggs and stratton engine, when I got it home I tried to crank it but it kept hanging on the comp. stroke so I did some research and then I set the valves to .005 on intake and .009 on exaust, set magneto to.010 and now it turns over and starts great but won't say running, PLEASE HELP??
