Thank you for your help with the piston. To follow-up, which is the right side of the piston? Is it towards the rear or front (of the tractor). Also, my supplier gave me a leather and a Teflon backer, is either better? This is my first hydraulic lift-piston service and the idea of an unattached piston is new to me. My guess is, since the force is being applied from the back of the chamber the backer would be on the opposite end of the piston: towards the rear of the tractor. Please correct me if I am wrong. November 3, 2014.
The top of the piston is the domed part with the slight projection. This top part goes into the cylinder first. The backup ring is put on first, I prefer the plastic backup ring but both kinds work. Move the backup ring to the bottom of the groove, so it is closest to the bottom of the piston, that’s the recessed end of the piston. The O ring is then installed on the piston so the O ring is closest to the top or domed part of the piston. Coat the inside of the cylinder and the piston and O ring with oil before pushing the piston into the cylinder. The recessed part of the piston is the bottom and this is the part of the piston you should seen when the piston is installed in the cylinder and where the piston will contact the rounded end of the connecting link or dog bone as it is often called. (The dog bone connotation comes from the original 9N, 2N design which has a ball at each end).