Purchase all new hardware for convertible top, Hydraulic cylinders and hoses from NPD and pump from classic Industries. The first problem was getting the hoses to seal to cylinders. The only way to stop the lines from leaking was to use Teflon tape and pipe sealing compound. Cylinder did come with O'rings. Ordered kit from Ames on how to bleed system. This was about 8 months ago the top has never worked correctly but would go up and down with a little coaching. Now its great weather and top is not working. Checked the fluid level and bleed for about the fourth time, not showing any air in system. I am thinking the cylinders are leaking down because if I stop top halfway down it will fall down fairly fast, leaking down. Disconnected cylinders from top frame and ran all the way up and down with pump slowing at each end stop. With cylinders disconnect top moves freely up and down. With everything connected when motor is running it sounds like it has no strain on it up or down. Called NPD about leaking hoses and they said technician would call me. I am waiting to this day for technician to call me so I do not believe they will help. How do I tell which component is failing.