tried searching and didn't come up with much. Have a 927A1 and havent run it much lately but decided to let it warm up and move it around the yard. One of the rear wheels doesn't seem to wanna release. I caged it and put a new diaphragm in it the 16 one. didn't seem to help. What should i be looking for. Grabbed a few of the 12's also should i pull that one apart?