Snorkel A38E-sn004500+ - Manual (Page 56)

Maintenance Section
4-26 A38E Work Platform
4.19 Slave Levelling Cylinder
(Figure 4-21)
REMOVAL
1. Ensure that the A38E is on firm level ground,
the Elevating Assembly is completely stowed,
the Keyswitch is to the ‘OFF’ position and the
Emergency Stop Button is pressed.
2. Provide a suitable container to collect the
hydraulic fluid, then disconnect the hydraulic
hoses. Immediately plug hoses to prevent
foreign material from entering. Support the
Platform
3. Remove securing bolts and pin lock plates from
the cylinder pins.
4. Support barrel end of cylinder and remove rod
end pivot pin. Move cylinder backwards allowing
it to hang freely. Rotate the cylinder backwards.
5. Support the cylinder so that the barrel end
cylinder pin can be removed, then remove the
cylinder from the machine.
6. Move the cylinder to a prepared work area. It is
important that clean assembly practices are
observed as seals and other hydraulic cylinder
components are highly sensitive to
contamination.
Figure 4-21: Slave Levelling Cylinder
DISASSEMBLY (Refer to Figure 4-16)
1. Unscrew the headcap and withdraw the rod and
piston assembly from the barrel tube.
2. Unscrew the piston nut and remove piston and
headcap from the cylinder rod.
3. Remove the piston static O-ring from the
cylinder rod.
4. Remove the piston seal from the piston.
5. Remove the rod seal, rod wiper and static seal
from the headcap.
6. Care should be taken to save the O-ring and all
other seals for reassembly, if they have been
deemed serviceable following the cleaning and
inspection phase of maintenance.
CLEANING AND INSPECTION
1. Clean all metal parts in solvent and blow dry
with filtered compressed air.
2. Check all threaded parts for stripped or
damaged threads.
3. Check the bearing surfaces inside of the
headcap, outer edge surface of the piston,
inside of the cylinder barrel and the shaft for
signs of scoring, pits, excessive wear or
polishing. Scratches or pits deep enough to
catch a fingernail are unacceptable. Polishing is
a sign of uneven loading and if sufficiently
polished the affected parts should be replaced.
4. Replace any parts or seals found to be
unserviceable.
REASSEMBLY/SEAL REPLACEMENT
1. Lubricate and install new rod seal, rod wiper
and static seal on the headcap.
NOTE: Multi-purpose lubricant should be used.
2. Install a new piston seal on the piston.
3. Install the headcap on the cylinder from the
piston end.
4. Install the piston, piston nut and a new piston
static O-ring on the cylinder rod. Screw nut to
end of thread and secure with circlip.
5. Lubricate the piston seal and install the piston
and rod assembly in the barrel tube.
6. Thread headcap onto barrel tube and hand
tighten, then turn 1/4 turn further.
7. Install the upper cylinder valve block. Check
O-rings.
4.19
1. Circlip
2. Barrel End Pivot Pin
3. Bushings
4. Pin Lock Plate
5. Rod End Pivot Pin
6. Slave Levelling Cylinder
1
2
3
4
6
5
Note: During seal replacement do not use sharp
edged tools to avoid cutting the seals, and allow
at least one hour for the seals to elastically
restore to their original shape before assembly.