valve guides and oil rings are most likely worn but a pcv valve can be stuck and blow blue smoke
Because the hairs in your nose filter the air
If by breather you mean the air filter......yes.
yes
Exhaust filter? Never heard of that filter.
an air filter
Because the breather system(Crankcase ventilation system) was routed to the air filter. Most people remove the line going to the air filter and route it to a breather filter which you may obtain from any Harley parts retailer. The problem is if you only ride your bike occasionally, it will continue to squirt when you first start it, do after installing the breather filter, remember to put a drain pan under it when you start it.
Fuel filter blocked or tank breather blocked
I am not aware of a breather filter on the 323. The breather hose on the valve/cam cover vents directly into the intake snorkel located between the throttle body and the air meter (the snorkel is the black oval shaped tube in the shape of an 'L') Cheers Malcolm
the valves or rings are allowing compression blow by to enter the crankcase which causes excess pressure that is brought to the carburetor by the breather tube. your engine is getting tired or you have too much oil in the crankcase.
bad filter
Crankcase breather tube.
Under the air breather... Remove air breather and look down right there and not too bad to get to. Hope it helps.