Mowing John Deere X500 54 in deck will not level

[trackerman]

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]When I try to level my 54 in deck on my x500 if I back off the rear adj nuts the deck will not drop on to the stops.And now it won`t lock in transport position. I bought it used , might have a lemon:

 

[rekees4300]

Here is the owners manual. It has instructions on mower leveling.

OMM146676_K6