TM5-6115-593-34 NAVFAC P-8-631-34 TO-35C2-3-463-2 generator away from engine enough to allow removal of coupling hub (61). WARNING OVERHEAD OPERATIONS HAVE INHERENT HAZARDS THAT CANNOT BE MECHANICALLY SAFEGUARDED.  HARD HATS AND SAFETY SHOES ARE REQUIRED . (c) Remove coupling hub (61) from shaft. Remove fan hub (73) by loosening screw (74) with washer (75) and loosen setscrews (76). (d) Remove fan (73) with hub (77) attached. (e) Remove hub (77) from fan (73) by removing screws (71) with washers (72). (2) Inspection.  Inspect fan hub and blades for visible signs of damage or wear. (3) Replacement.  Reinstall fan as follows: (See figure 11-3.) (a) Attach hub (77) to fan (73) with screws (71) and washers (72). (b) Attach coupling hub (61) to drive plate assembly (59) with screws (57) and lock in place with lockplates (58). (c) Attach adapter (70) to generator frame with screws (68) and washers (69). (d) Insert baffle (78) and fan (73) into adapter (70). (e) Slide coupling hub (61) (with drive plate assembly) onto generator shaft aligned with fan hub (77) with both keys (62 and 79) in keyways. CAUTION Make certain that before generator set is placed in operation, fan is positioned with about 1/2 inch (13 mm) clearance between fan and baffle and all fan bolts are installed and tightened. (f) Tighten screw (74) with washer (75) on fan hub (77).  Tighten setscrews (76) on fan hub (77). (g) With crane, move generator back to its original location and tighten mounting bolts. Refer to figure 11-5. (h) Replace covers (63 and 67), bolts (64), washers (66), and nuts (65). 11-12.  ROTOR ASSEMBLY.  The rotor assembly is supported at one end by a single bearing in an endbell bolted to the stator frame.  The opposite end of the rotor is provided with a fan assembly and drive plate assembly which bolts directly to the engine flywheel. a. Inspection. (1) Inspect rotor for loose, frayed, or burned windings. (2) Inspect shaft for burrs or signs of wear. (3) Inspect rotor assembly for cracks or other signs of damage. b. Test.  Check field winding resistance and shorts as follows: (1) Connect a Wheatstone bridge to field winding leads. (2) The resistance shall be 1.691 to 1.725 ohms at an ambient temperature of 77°F (25°C). (3) Megger between field leads and rotor frame with a megohmmeter to measure the resistance between the winding and frame. 11-29