Remove the 2 valve springs on #7 hole and replace the seals. While the springs are off, check for valve guide ware. Worn or not, put it back together and see if the problem has gone away. If it's still using oil, Pull the intake and check to see that the intake gasket is sealing properly around that hole ( valley area inparticular ). If all looks ok, pull off the left side head. At this point in disassembly, you should be able to find the problem.