11
7. Pilot Valves, Valve Seats and Spring
7.1 Removal
- Remove the diaphragm and center rod.
(See Section “6.1 Removal”)
- Use the dedicated tool
①
(pilot valve remover) to remove the 2
seat stoppers. [Fig.7.1]
- Remove the O ring, valve seat and pilot valve. [Fig.7.1]
7.2 Inspection
- Pilot valve assembly [Fig.7.2]
Measure the diameter, and if it is out of the allowable range,
replace the pilot valve assembly with a new one.
Allowable range
φ
4.8 -
φ
5.0 mm
- Valve seat [Fig.7.3]
Measure the inside diameter, and if it is out of the allowable
range, replace the valve seat with a new one.
Allowable range
φ
7.0 -
φ
7.2 mm
- Spring [Fig.7.1]
Be sure to replace the spring with a new one when
disassembling the pump regardless of its condition.
- O ring [Fig.7.1]
If the O ring is worn out or damaged, replace it with a new
one.
7.3 Installation
For installation, see [Exploded View] on the separate sheet and install in the reverse order of disassembly.
＜
NOTE
＞
- Be careful not to remove the O ring located on the valve seat
when installing any part to the pump.
- Be sure to fix the seat stopper into the body until it reaches
the end face of the body securely.
- Make sure that there is no dust on the seal surface and that
the seal surface cannot be damaged.
- Use the dedicated tool to attach the seat stopper.
Fig.7.1
Fig.7.2
Fig.7.3