It's not just a grinding sound, it flat won't start. Yesterday after assembly no grinding at all. Fired right up, I turned it off no clunk....perfect. I started it again a couple times everything was awesome. I picked up then started it and let it warm up. All of a sudden at about 172 degrees I hear it. Turn it off and it grinds. Take it all apart do it again this time tight as a nuns ******* and same thing. I cuss my stupidity at using locktight 262 and today everything back apart reassemble with high heat locktight and borrow neighbors air impact and go nuts. Exactly the same thing. Wtf. I love precious, but if I can't ride her what's the f'n point!