A lot of people say the knob just freezes up or is hard to turn. It just needs a little love. Below in the picture I pointed out the area to spray some lube (I use JD Superlube from the dealer) and your worries are over. For further lubrication lay under the deck and spray the upside down circular staircase doohickey. This will alleviate a lot of friction caused by dust and debris Thought I d share