These images cover the procedure for replacing the oil of a sachs shock absorber used on different models. the operation also involved the reduction of the center distance of the fixing holes which went from 440 millimeters originally to 430 millimeters after shortening the sheath by 10 mm. This is to obtain a lowering of the saddle of about 3 cm on my TE630. It starts by removing pressure from the valve on the external tank. At this point it is possible to lower and remove the valve holder by removing a sealing ring. Once the tank cover has been removed, the seal unit on the body can be lowered to remove another steel ring that blocks the seal. At this it is possible to extract the stem to completely empty the oil to be replaced. The oil visible in the photos is about 10 years old and was still in good condition with light wear residues. At this point reassembly can begin with the introduction of new oil which must take place from the external tank keeping the high and low speed compression adjusters all open. In about 30 minutes the oil gradually poured into the tank will flow into the body making possible air bubbles come out. Once the external tank has been filled to the maximum, it is necessary to reinsert the gas / oil separator septum which will be pushed to the end of its stroke on the bottom of the tank. At this point you will have transferred all the oil from the tank into the body which will show a certain level of oil. At this point, attach a sort of body extension funnel because you will have to add oil up to about 4 centimeters beyond the body itself. This procedure is necessary as it is necessary to reinsert the pumping unit with the blades without allowing air to remain inside (this is the most difficult phase). For this, insert a shim under the slats to let the trapped air flow out when you reinsert the body. View: https://youtu.be/cpcRFOJn4VM
