Thermo King SB-190 30, Manual

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Refrigeration Service Operations (Rev. 12/03)
74
CAUTION: Do not force the tool into the brass
or against the bolts.
Gasket Tool P/N 204-424
5. Remove the four bolts from the valve.
6. Remove the top cap and spring.
7. Remove the spring clip which secures the stem to the
piston. Slide piston off the stem.
8. Remove the seat and stem assembly.
9. Inspect the following parts for wear or damage:
a. Bottom cap, sealing and support area.
b. Seat, sealing surface.
c. Top cap, sealing and support surface.
The following parts will be discarded:
a. Stem assembly.
b. All gaskets.
c. Piston seal.
10. Remove the screen. If any particles drop from the
screen into the discharge line, the discharge line must
be removed at the compressor.
NOTE: The valve body cannot be reconditioned. Seat
positions change and improper sealing will result.
Assembly/Installation
After cleaning and inspecting all parts, reassemble the
valve.
1. Install the screen in the bottom cap.
2. Install the new stem in the bottom cap.
3. Install new gaskets on both sides of the seat. Oil the
gaskets in compressor oil before installing.
1. Seal Groove in Piston
2. Connecting Notch in Piston
3. Internal Spring in Seal
4. Connecting Groove in Stem
5. Retaining Clip
Piston & Stem Parts
2
5
4
3
1