I recently changed a timing belt for the first time, and except for a stuck camshaft bolt (thanks to all here who helped me with that), everything went well.
Today not so lucky. On my 87 740, after I lined up the crank shaft pulley marks with the lower timing belt cover 0, I used the center-counterhold tool, securing it to the tensioner with the tensioner nut; after I got the bolt out on the crankshaft pulley, I unscrewed the tensioner nut to remove the counterhold, and before I could reassemble the tensioner nut, the tensioner shot over to the right, with the tensioner bolt as far left as it could go.
When I checked the camshaft, the mark on the pulley had moved away from the rib (where it had been) on the back of the timing belt cover, and the crankshaft pulley marks were way off too.
I rotated the camshaft gear to get the mark on it to correspond with the one on the back timing belt cover, but the crankshaft pulley marks were about 20 degrees to the left of the 0.
The car doesn’t run well now; it stalls after idling for about 10 seconds.

Should I have rotated the crankshaft pulley around the other way a couple of times? Or has one of the gears moved independently? This seems unlikely since the old belt was on when the spring sprung. Do you have any suggestions before I take everything apart again?

PVC