are the boxer motors interference styl motors? i was told by mech. that motor is locked up but im hoping i threw a timming belt and maybe bent a valve which is jamming a piston making it seem like it is locked up but not completely trash. they want $720 just to tear apart but i am not going to pay that if it is something i can do myself. would rather rebuild than replace. anybody had simmilar situation or know if motor is an interference style or not?