Looking at getting another Supra... Has a strange motor issue. The seller said it had a light top end knock/tick but still ran fine then one day the motor just quit. Said it wont turn over by hand. I know 7Ms are non interference so I'm pretty puzzled about this. The best I can come up with is either it jumped time by a lot or the CPS somehow broke and is binding the exhaust cam. Even if a valve fell all the way down in the cylinder, landed perfectly concave side down and the stem is now hitting the head it'd still spin backwards right?