At low idle for the past couple months there has been a noticeable rattle from the bottom end. I figured something is going or the pulley on the shaft was dented causing it. At high idle I couldn't hear it no more. Well the other day after mowing I was going up the drive to the garage, the engine seemed to load up and when I made it into the garage she went boom. Soooo the question is what is the average price parts wise for a rebuild? Rings, gaskets, bearings. Just trying to figure if it's worth rebuilding or replacing. Also if I do rebuild, any one put larger pistons or change the stroke for more hp?