ok the hh120 that had a bad knowck after piston and rings heres the lates
I tore it down pulled the piston pulled the crank pulled the cam all MIC out to spec. I did notice that it looked as if the mag on the flywheel was hitting the ssi ???? not sure how thats posible but could that be my knockin noise
Tecumseh actually has a kit with shims i bought once that u use...for the flywheel side..and then to adjust preload take out the shim on the sump cover side..that will make the preload tighter, thats what the white thin gaskets are for...
If ur napa store has a decent machine shop have them check it...They can tell you if its round or not...most likely the rod could be worn....its softer then the crank...and if cranks turned, then u replace rod with an undersized rod..