Turtle Refill Lava

function aboutFace()
   turtle.turnRight()
   turtle.turnRight()
end

function retrieveBucket()
   turtle.up()
   turtle.forward()
   while turtle.getItemCount() == 0 do
      turtle.suckDown()
   end
   aboutFace()
   turtle.forward()
   aboutFace()
   turtle.down()
end

function pulseRedstone(side)
   redstone.setAnalogOutput(side, 8)
   sleep(1)
   redstone.setAnalogOutput(side, 0)
end

function dropBucket()
   turtle.drop()
   pulseRedstone("front")
end

while true do
   retrieveBucket()
   if turtle.getFuelLevel() < 500 then
      print("Attemtping to refuel...")
      turtle.refuel()
   end
   aboutFace()
   dropBucket()
   sleep(15)
end