Dont worry about the breather....they "never" good bad.
When you replaced the 2 o-rings on the main nozzle, are you sure you removed the old one. (The top one usually stays put and has too be dug out.)
When I remove the nozzle there was no o-rings there.
Are the governor-carb linkages as they were before you removed the carb?
I pretty sure, not 100% positive.
Again...make sure it is priming when you press the primer bulb. (You should see it coming out of the end of the main nozzle, into the throat of the carb.)
Do I perfom this with the carb off the engine?
Be sure that # 241 is in place....screw #238 must be in its holes, or the carb will never prime. (The screw blocks off a common passage that it shares with the primer system.) Without the screw in place....the primer charge just blows out of the hole and doesnt reach the float bowl.
The two screws are in the holes.