① Disassembly of the relief valve assembly of the excavator Remove the relief valve assembly, as shown in Figure 3-49
② Disassemble the supplementary valve and bypass valve assembly.
Loosen the cover, and remove the supplementary valve and spring, and remove the bypass valve assembly, as shown in Figure 3-50.
③ Mark the rotary motor. Before removing the motor, make a mark between the cover and the case for reinstallation, as shown in Figure 3-51.
④Remove the mounting bolts of the cover.
Use a wrench to loosen the hexagon bolts, as shown in Figure 3-52
⑤ Remove the cover assembly.
Place the motor assembly axially downward, as shown in Figure 3-53, and then remove the cover
⑥As shown in Figure 3-54, remove the snap ring with a steel rod, and remove the inner ring of the needle roller bearing with a bearing remover.
⑦ Remove the O-ring from the cover, as shown in Figure 3-55
⑧ Remove the balance plate.
The balance plate is tightly attached to the surface of the cylinder due to the effect of oil viscosity. Remove the balance plate by hand, as shown in Figure 3-56.
Before disassembly, check and record the position of the balance plate to facilitate installation.
⑨ Remove the bushing and cone spring from the Teflon ring, as shown in Figure 3-57.
⑩0 Remove the spring Remove the spring from the plunger, check and record the original position of each spring for reinstallation, as shown in Figure 3-58.
①Remove the brake plunger. When the plunger is removed from the shell, there is sliding resistance against the O-ring, and the M6 bolt is installed on the connecting hole of the plunger, as shown in Figure 3-59.
①Remove from the plunger. Shaped ring and shell, as shown in Figure 3-60.
③3 Remove the friction plate and lining from the shell, as shown in Figure 3-61.
④Remove the cylinder assembly.
Hold the bottom of the cylinder assembly with your hand and pull the cylinder assembly out of the housing, as shown in Figure 3-62.
The outer ring of the oil seal and tapered bearing is located on the left side inside the shell. The end face of the cylinder is smooth, so the end face should be protected from damage caused by foreign objects. Make a position mark between the plunger hole of the cylinder and the plunger assembly to install the plunger to its original position.
⑤ Remove the outer ring of the tapered bearing from the shell, as shown in Figure 3-63
⑩ Remove the oil seal.
Remove the oil seal from the shell with a bolt knife and hammer, as shown in Figure 3-64.
After disassembly, do not reuse the oil seal.
①Removal of plunger cylinder assembly:
A. Remove the inner ring of the tapered bearing. After removing the snap ring, use the gear puller to act on the spline end of the cylinder
The cylinder of the inner ring of the rolling bearing is raised, as shown in Figure 3-65.
B. Separate the cam plate, plunger assembly, and return plate from the cylinder, as shown in Figure 3-66.
C. Remove the cam plate on the sliding surface of the plunger assembly, as shown in Figure 3-67.
D. Remove the spring from the plunger, as shown in Figure 3-68.
So far, the disassembly work is completed.
