Repairs
36
Service manual
Filling new hydraulic cylinders with oil and de-aerating
them
The two new hydraulic cylinders for back section
adjustment together with the hydraulic hoses have to be
filled with oil.
•
In order to fill the new hydraulic cylinder with hydraulic
fluid, push the piston rod in completely and suspend
them, hose connections pointing to the floor, from the
corresponding bearing at the seat section frame.
•
Connect the hydraulic hoses firmly to the piloted check
valves. Connect the ends of the hoses loosely to the
hydraulic, pulling the hoses slightly out of their
bearing.
•
Pump the hydraulic fluid carefully through the hoses to
the hydraulic cylinders using the foot pump in “Raising
back section” position. As soon as hydraulic fluid
emerges from the loosened screw joints, tighten the
screw joints. Then make the hydraulic cylinder extract
completely.
•
Loosen the screw joints at the hydraulic cylinder again,
pulling the hoses slightly out of their bearing.
•
Pump the hydraulic fluid in “Lowering back section”
position carefully through the hoses to the hydraulic
cylinders. As soon as hydraulic fluid emerges from the
loosened screw joints, tighten the screw joints.
•
Go on pumping carefully until the air has been
discharged from the piston rod end and through the
loosened screw joints. Retighten the loosened screw
joints.
•
Make the hydraulic cylinders retract completely.
•
Adjust the hydraulic cylinders in such a way as to make
the hose connections point to the ceiling. Repeat the
procedure at the piston end of the hydraulic cylinder
in order to de-aerate the system.
•
Loosen the hoses at the piloted check valve and screw
a stopper immediately onto the hoses.
The hydraulic cylinders are now de-aerated and can be
installed.
Installing the hydraulic cylinders
•
Install the hydraulic cylinders for back section
adjustment in reverse order. Observe the different
length of the bearing bolts.
Final works
•
Check the functioning of the hydraulic cylinders.
