Prairie 650 engine trouble

[Prairie_Style]

Hi i just recently brought my 02 prairie out of storage, witch has been sittingit its trailer with a tarp over it sense 04 cause one of the roller bearings broke on the spider inside the clutch. well make a long story short i finally got it all fix and put together and fired her up today for the first time in 5 years. i have two problems. first is doesn't want to run very good. ill put some sea-foam in the gas cause i think the jets might be plugged, and second in back of the breather box theres a small hose attached that goes to i think the crank case. well after letting it warm up a lil bit it starts to shout wut looked like gas/oil mix out of the hole in the breather box and its filling the whole breather box full of the oil mix. i put my finger in the hole to plug it and theres alot of pressure being built up. dose anyone know wut would cause this cause I'm relay stumped!
thanks for any help

[2fun]

First off, you need to empty the entire fuel system and give the carb a good cleaning. Then get fresh fuel in there. After sitting that long, crap gets all gummed up.

Not too sure about the crank case breather hose.
Maybe someone else can chime in on that one.