OT: but need help with honda 8hp motor

[thisolechevy]

Hi there I nknow this is off topic but everybody here is so helpful. The problem is I got a free honda 8hp gx-240 from my uncle because it was froze up. I took the head apart and unfroze the motor reassembled and ther was absolutly no compression what so ever. I then decided to re-build it and got it all assembled last night (new rings, piston top, gasket, pretty much everything) stupid me gets in a hurry when disassembling and I forgot to mark the gears in the block for re-installation sooo I just put it all back together where it looked right and nothing hit :-) I went to check everything before trying to crank and there is still no compression
whats up with that??? the "pcv" valveon the valve cover has lots of compression? where there is practically nothing coming from the exhaust or plug hole? what wrong with this motor.
I was wondering if the gear that ran the valves could be on backwards and creating compression in the place? is this possible? and also I tightened the vlave springs all the way down and tehn lossened them a full turn for lack of torc. wrench. will this do? or do I need to get one?
Sorry fo the long post but I am lost