General Cylinder Repair; Preparation; Cylinder Disassembly - Mec 4069RT Service And Parts Manual

P
R E P A R A T I O N
Take precautions to protect the rod surface. Guard against dirt or other
foreign objects entering system.
1. Drain all fluid from cylinder.
2. Clean all dirt and grit from outside of cylinder.
3. Insert cylinder into vise.
C
Y L I N D E R
1. Remove the head from the cylinder body.
2. Remove the shaft assembly from the barrel, pulling in a straight line, so as not to scar
the internal parts.
3. Insert shaft into a soft jawed vise so that the head and piston can be removed. Be
sure the shaft and vise are both clean before using.
4. Loosen the set screw from the side of the piston. Using a piston removal tool,
unscrew the piston from the rod. It may be necessary to heat the piston to 200° F
5. (93° C) to loosen the Loctite.
6. Remove all seals from the head and piston using a non-sharp seal tool. These tools
are available from various seal suppliers.
7. Clean all fluid and debris off of the head, piston, shaft, collar and barrel using solvent,
rags, and an air hose.
8. Inspect parts for scratches, pits or polishing. Check seal groves and sealing surfaces.
a. Scratches or pits deep enough to catch the fingernail are unacceptable; replace the
cylinder.
b. Polishing is a sign of uneven loading. Check for roundness. If a polished surface is
not round within .007 in. (0.18 mm) replace the cylinder.
Assembly is reverse of disassembly. Lubricate all seals with clean hydraulic fluid before
assembly. Use Loctite when securing the piston to the rod.
March 2014
Page 1-26
D
I S A S S E M B L Y
"4069RT" Service and Parts Manual
G C R
E N E R A L Y L I N D E R E P A I R