YAMADA NDP-H40, Maintenance Manual, Page: 8 / 18

5
4.2 Inspection
▪
Ball [Fig.4.10]
Measure the outside diameter, and if it is outside the
usable range, replace the ball.
Usable range of ball
NDP-H40 S
Ø
45.0 ~ S
Ø
51.5 mm
NDP-H50 S
Ø
56.7 ~ S
Ø
64.9 mm
NDP-H80 S
Ø
81.0 ~ S
Ø
92.7 mm
▪
Valve seat [Fig.4.11]
Measure the dimension shown at left, and if it is outside
the usable range, replace the seat.
Usable range of valve seat
B
□
C, B
□
N, B
□
E
B
□
V, B
□
H, B
□
S, B
□
H/T
B
□
T
NDP-H40 4.6 ~ 11.5 mm
1.7 ~ 4.2 mm NDP-H50
5.0 ~ 12.5 mm
NDP-H80
▪
O ring (other than PTFE)
If O ring is worn out or cracked, replace it.
4.3 Installation
For installation, see [Exploded View] on the separate sheet and install in the reverse order of disassembly.
<NOTE>
▪
Make sure there is no dust on the seal surface and the
seal is not damaged.
▪
Match the convex and concave parts of the protector.
[Fig.4.12] ( NDP-H50 BP
□
•H80 BP
□
)
Tightening torque for manifold retainer bolts
BA
□
, BS
□
BP
□
, BV
□
NDP-40 25 N•m 20 N•m
NDP-50
25 N•m
NDP-80