I just rebuilt the hydraulic lift. New gaskets, o-rings, and through cleaning. I removed all threaded plugs and sprayed brake cleaner through all the passages. Pulled out the sliders and cleaners the small holes. Cleaned the check valve ball. I went through the adjustment procedure in the IT manual but didn't have the n502b gauge. So I found a alternative procedure on the other n tractor site under "How-to's" titled "Hydraulic Control Adjustment Procedure - NAA". I used 1/4" and 3/16" key stock as feeler gauges. The lift lifts strong and goes all the way up, but will not return to the start position. It stops about 1/3 up. What did I do wrong?