I'm guessing rings are a problem as you most likely have excess blow by. You could check compression but I'm not sure what spec you require. Check to see if the breather is not blocked. If not I would assume you would be getting oil out the breather as well. Best bet is the take the head off and inspect the bore. Hopefully no scratches otherwise you may be able to hone it out. If your mechanically minded put new rings with maybe a hone.
