Was it running before you took it apart?
If so it can't be something you haven't played with.
Are you certain the distributor is pointing at 3? Are you sure it's not pointing at #4?
If distributor is pointing at #4, then #1 cylinder is on exhaust stroke. Take off the belt and turn crank 360.
Camshaft, #1 cam lobes should be furthest away from valves, #4 intake should be just closing, exhaust just opening (rocking).
1 3 4 2 firing order, #4 will be on the opposite stroke to #1 cylinder. Same with 3 and 2, but that's not important for timing.