Originally Posted by DennyW
If it's not smoking out the tail pipe, and the PCV valve is working, you need to pull the valve covers, and check the oil drains in the head. Also, if it smokes when you first start it up, that is an indication that the valve seals are probably bad. That, along with plugged oil drains will cause this. Also, if the drains are plugged, the PCV valve cannot pull the vapors from the opposite side. Which causes smoking (blowby) to continue coming out the valve cover. And make sure the breather side breather is clean.