HF-7-600 Page 19
SECTION 6
DISASSEMBLY INSTRUCTIONS
1. Remove the screws (46) and lockwashers (48) from the port connectors. Remove the connector (52)
and gasket (51) from the inlet and discharge ports.
2. Inspect the interior of the blower for any signs of rotor contact (rotor to rotor, rotor tip to case, rotor end to
bearing housing). If there are signs of contact then the various clearances should be measured with feeler
gauges prior to any disassembly.
3. Inspect the areas around the drive shaft seal and vent passages in the bearing housing and air cylinder for
any signs of oil leaks.
4. Drain the oil from the gear end and drive end sumps by removing their drain plugs (2). A small amount of oil
from each sump should be saved in the event that an oil analysis will be required.
5. Remove the screws (5) from the drive end sump cover (29). Remove the sump cover by sliding it off the drive
shaft.
6. Inspect the drive shaft in the area of the oil seal for damage and wear. Inspect the oil seal (31).
7. Support the external surface of the drive end sump cover near the oil seal with blocks of wood. Drive the oil
seal from the cover using the seal driver tool (EQ143956) and a press or small hammer.
8. Remove the screws (5) from the gear end sump cover (3). Remove the sump cover.
9. Remove the bolt (8), washer (6), and oil slinger (26) from the gear end of its rotor shaft.
10. If it appears the gears can be reused their backlash should be measured. Lock the idler rotor from turning by
wedging a shop rag between the tip of a lobe and the air cylinder. Measure the backlash of the gears using a
dial indicator and a magnetic base. The backlash should be measured in 3 places (every 1/3 turn).
11. Match mark the gears by making small punch marks on the ends of 2 meshing teeth.
12. Remove the 3 set screws (57) from both gear locking assemblies (56). Note these are located through the
unthreaded holes in the outer ring.
13. Remove the 6 capscrews from both gears. Thread 3 of these capscrews into the threaded holes in the outer
ring of each locking assembly. Tighten the screws evenly to remove the locking assembly from each gear.
14. Remove the gears (9) from both rotor shafts.
15. Remove the stepped spacer (55) from each rotor shaft.
16. Remove the 4 bearing retaining screws (10) and washers (12) from the air cylinder.
17. Position the blower assembly vertically with the drive end up. Support the gear end of the air cylinder on
blocks to protect the ends of the rotor shafts.
18. Remove the locknuts (36) from both of the rotor shafts on the drive end using nut driver tool (EQ143816).
19. Remove the oil slinger (27 & 83) from its rotor shaft.
20. Remove the spacer (49) from each rotor shaft.
