Thermo King T-500R Maintenance Manual page 236

8. Inspect all the parts (replace if excess wear is found).
a. Piston and cap for wear (scuff marks)
b. Body for stripped threads
c. Bellows end cap for damage in pilot hole
NOTE: Bellows is normally replaced.
.
9. Clean the parts to be reused.
Reassembly
1. Install new bellows with O-ring into the housing.
2. Center the spring on bellows shoulder.
3. Oil the gasket (same type of oil that is used in the system), install on the body, and place shims in end cap (use same number
as removed). Tighten end cap in place with vent hole closest to outlet opening of the valve body.
4. Install the piston, spring and tighten the castle nut until firmly seated against the bottom of the piston.
5. Back off the castle nut, one full turn only.
6. Insert the cotter pin.
1. Inspect for Wear
Throttle Valve Piston
1. Inspect for Damage
Throttle Valve Housing
Refrigeration Maintenance 10-52