This would be a tough one to call without having the motor in front of you .... cam belt hasn't parted and still seems to have some tooth presence even at the tear ... we presume the bolt has got between the belt and the toothed pulleys ... if so, as it went over the top it would have 'adjusted' the cam timing ... possibly enough to cause contact ... as Deejay says, a compression tester is cheap and will be more reliable than sticking your thumb over the plug hole ... looks like the pulleys need checking for damage. Dropping a new belt on and cranking it over will tell you if you really do have lower compression on a couple of cylinders ... if so, enough valve damage to prevent proper seating is probably a likely candidate ... good luck and keep us informed as to how you get on
K
