Vehicle System Testing and Adjusting 43
Lift Cylinder Air Removal (Only FFT &
FFL Mast)
After the lift cylinder has been disassembled and
then assembled again, it may be necessary to
remove the air (bleed) from the cylinder.
1. With no load, lift and lower the mast and carriage
through several complete cycles.
2. With the forks on the floor, check the oil level in
the hydraulic tank. Add oil (if necessary) to bring
the oil level to the full mark.
3. With no load, lift and lower the mast and carriage
again through several complete cycles.
WARNING
The oil will have high pressure. To prevent
personal injury, do not remove the bleed screws
completely. Keep hands and feet away from any
parts of the truck that move, because the forks
will lower when the bleed screw is loosened.
4. Lift the forks high enough to put a load on all
stages of the lift cylinders.
(Typical example) Setscrew Locations (Standard Cylinders)
NOTE : The Full Free and Full Free Triple Lift mast
has one primary and two secondary cylinders.
5. Locate the setscrew on each lift cylinder. Slowly
open setscrews no more than one turn. The
weight of the carriage will force air and hydraulic
oil out of the cylinders through the setscrews.
Close the setscrews before all the pressure is out
of the cylinders. This will prevent air from entering
through the setscrews.
6. Repeat Steps 4 and 5 until there are no air
bubbles at the setscrews.
7. After all the air is removed, tighten the setscrews
to a torque of 5 to 7 N·m (45 to 60 lb·in).
8. Fill the hydraulic tank to the full mark.
9. Lift and lower the mast and carriage again
through one complete cycle. If the mast does not
operate smoothly, repeat Steps 3 through 9.
NOTE : Standard lift cylinder doesn’t need air
removal because its return line is connected to the
oil tank.
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