Yanmar ViO12-2A, Руководство по обслуживанию

Страница: 201 / 409

6.
HYDRAULIC SYSTEM
6-
6
-10
6. Disassembly and Reassembly
1) Precautions for Disassembly and Reassembly
• Precautions for disassembly
(1) Since the parts of the hydraulic equipment are precision-made for tight clearances, be sure to perform disassem-
bly and reassembly in a clean area that is free from dust.
(2) Prepare clean tools and treated oil, and handle the parts carefully.
(3) First clean the external surfaces of the removed assemblies.
(4) Before beginning disassembly, review the drawings of the internal structure and prepare the required parts
according to the purpose and extent of the disassembly.
In principle, replace the removed seals and rings with new ones. As some replacement parts are available only
as a subassembly, refer to the parts catalog to prepare the necessary subassemblies in advance.
• Precautions for reassembly
(1) Handling of O-rings
[1] Lubricate the O-rings and the O-ring fitting seats with clean grease or hydraulic oil.
[2] Do not damage the O-rings in handing or distort them by heat.
[3] Do not stretch the O-rings so strongly as to deform them permanently.
[4] Avoid rolling the O-rings when fitting them.
A distorted O-ring may not return to its original shape, and therefore, may cause oil leak.
(2) Before beginning reassembly, check that the mating surfaces of each section have no treated oil or hydraulic oil
on the outer surface of the O-ring grooves in them. If reassembly is performed without such oil, it may be mis-
taken for oil leak.
2) Tools for Disassembly and Reassembly
Tool Nominal size Remarks
Hexagon socket screw key
(Hexagon wrench)
(
mm
)
3 For hexagon socket set screw M6
4 For hexagon socket head bolt M5
5 For hexagon socket head plug R (PT) 1 / 8
6 For hexagon socket head plug G (PF) 1 / 4
8 For hexagon socket head plug G (PF) 3 / 8
Wrench or box wrench
(mm)
8, 10, 13, 21 and 22
Screwdriver for cross recessed
head screws
For cross recessed pan-head screw M5
Rod (mm)
Ø
45 to 100
For disassembly and reassembly of spring center
Torque wrench (N·m)
1
9.6 to 98.1
Smaller than 19.6
For system relief valve, circuit relief valve, and anti-cavita-
tion valve
For nut M8, spring case and pilot case