i have an xtm 24.7 engine and i have tried os 8s,a5s, mcoy mc 9s and it is blowing them i have leaned it out a little on the bottom as it was just doing it at idle and it helped but after it runs awhile it blows it. i say blow it kind of crams the coil up inside of it please help me out with this thanks. chuck

That happend to my a while back. I had a leak at the top of the piston because it wasnt tightned down all the way or the exhaust is leaking.

already checked that

Is the plug burnt on the bottom??

no the coil is cramed up in it

make sure you have the head shim in