I have recently changed the harmonic balancer in my Volkswagen Passat 1.8 litre non turbo and had to remove the timing belt from the camshaft pulley - which was fine.

I aligned everything to its correct position. But now when I try to turn the engine by hand via socket and ratchet on the crankshaft it locks up at about half a turn and wont budge. I have tried a few different things but I am stumped at what it could be? My car is automatic and I have tried all this while it was in the park position - does this matter?