Thermo King recommends changing the compressor shaft seal when there is a major system interruption, such as component replacement or total loss of refrigerant charge. When the shaft seal is changed, Thermo King also recommends changing the oil and oil filter.
The steps for changing the shaft seal are as follows:
1. Recover refrigerant. Equalize pressure to slightly positive.
2. Remove compressor.
3. Remove drive pulley and Woodruff key from the shaft.
4. Clean shaft seal cover of excess dirt.
5. Remove four Torx head screws from shaft seal cover.
6. Carefully pry the shaft seal cover out of compressor body using flats at top and bottom of shaft seal cover.
7. Remove the old hard ring, lip seal, and o-rings from the seal cover.
8. Loosen the set screws that secure the bellows to the shaft. These set screws typically use an 1/8 inch Allen wrench which is provided with the new seal.
9. Remove the old bellows from the shaft. Use a small prybar or screwdriver on each side of the bellows, but do not scratch the shaft when removing the bellows. Be careful not to loose the spacer that is on the shaft.
10. Ensure the spacer is properly located on the shaft flat.
11. Back out the set screws from the new bellows and apply a small amount of removable thread locking compound (LoctiteTM see Tool Catalog) to the set screw threads.
12. Apply clean compressor oil to the o-ring inside the bellows and place the bellows on the shaft. Leave the orange protective cap on the bellows.
13. Use seal installation tool (see Tool Catalog) to install the bellows squarely on the shaft. Clean the seal installation tool and place it on the shaft. Turn the knob until the tool bottoms out.
14. Tighten the set screws to approximately 45 in.-lb (5.0 N•m) with the Allen wrench provided.
15. Remove the seal installation tool.
16. Install the new lip seal in the seal cover with the lip side facing out and the flat side facing toward the compressor.
17. Apply clean compressor oil to the new o-ring and install it in the seal cover. Apply clean compressor oil to the new hard ring. Ensure that the hard ring installation tool (see Tool Catalog) is clean. Use the hard ring installation tool to push the hard ring (with the polished surface toward the installation tool) fully into the seal cover. Do not pinch the o-ring.
If the installation tool is not available, use the pad in the new seal packaging to protect the polished surface of the hard ring during assembly. A substitute installation tool should have a diameter approximately the same size as the O.D. of the polished surface.
18. Remove the orange protective cap. Clean the hard ring and the primary ring (bronze ring) with the alcohol wipes found in package labeled “1”. Then clean the polished mating surfaces of both rings with the lint free dry wipes from package number “2”. Apply clean compressor oil to polished surfaces of the seal and to the lip seal from package number “3” before assembling.
19. Lubricate the new seal cover o-ring with compressor oil (see Tool Catalog) and install on the seal cover.
20. Install the seal cover on the body and torque screws to 100 to 110 in-lb (11.2 to 12.4 N•m). Do not bump the hard ring into the end of the shaft during assembly.
21. Install the Woodruff key and drive pulley. Torque the pulley bolt to 30 to 35 ft.-lb (41 to 47 N•m).
