Derrick,
Ok when you changed the blades was the engine still warm?
If so the oil would have run through the breather into the cylinder and then push out into the exhaust.
What I want you to do is clean the sponge air filter and then put it back on.
Then put some fuel into the cylinder to wash out it out. To do this you will leave the plug out and make sure that when you pull the starter rope(about six times or more) the throttle is in the stop position. This will get the excess oil out.
Then replace the plug with a new one and start the motor up and run for about 15 minutes or until it stops smoking.
Problem should be fixed.
Let us know as this will help others on the forum.
