Originally Posted by Meatbawl
/\sure, I'll agree...but only because it can't harm anything to try. I've done a timing belt change 6 times on WRX's in the last 6-8months... each time, the cams will pop and go out of alignment when you take off the tensioner...they will not stay. And since you'll be lining up the crank mark first, that will put the pistons where they need to be anyway. But try it, there's nothing to lose but 20 seconds of your time giving it a shot....but to me, it's like wiping before you poop...it's gonna get messy anyway
Ok fair enough. So just so I am clear:
I can take the belt off at any crank angle.
Upon removing the belt, the force of the valve springs pushing the lifters against the cam lobes will cause the cams to turn, and put the valves in a closed (safe from piston) position.
Before putting on the new belt, I must first turn the crank until its mark ligns up (I can turn the cranks because the valves are all closed).
Only then can I turn the cams to their marks, and only in the order which you describe.
It seems to me that if you tried to turn the cams to their marks, and THEN turn the crank to its mark, the piston could strike one of the opened valves. Correct?
So order is everything.