generator away from engine enough to allow
removal of coupling hub (61).
OVERHEAD OPERATIONS HAVE INHERENT
HAZARDS THAT CANNOT BE
MECHANICALLY SAFEGUARDED. HARD
HATS AND SAFETY SHOES ARE REQUIRED .
Remove coupling hub (61) from shaft.
Remove fan hub (73) by loosening screw
(74) with washer (75) and
loosen setscrews (76).
Remove fan (73) with hub (77) attached.
Remove hub (77) from fan (73) by
removing screws (71) with washers (72).
Inspection. Inspect fan hub and blades for visible
signs of damage or wear.
Replacement. Reinstall fan as follows: (See
Attach hub (77) to fan (73) with screws (71)
and washers (72).
Attach coupling hub (61) to drive plate
assembly (59) with screws (57) and lock in
place with lockplates (58).
Attach adapter (70) to generator frame with
screws (68) and washers (69).
Insert baffle (78) and fan (73) into adapter
Slide coupling hub (61) (with drive plate
assembly) onto generator shaft aligned with fan hub (77)
with both keys (62 and 79) in keyways.
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
Tighten screw (74) with washer (75) on fan
hub (77). Tighten setscrews (76) on fan
With crane, move generator back to its
original location and tighten mounting bolts.
Refer to figure 11-5.
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.
Inspect rotor for loose, frayed, or burned
Inspect shaft for burrs or signs of wear.
Inspect rotor assembly for cracks or other
signs of damage.
Test. Check field winding resistance and
shorts as follows:
Connect a Wheatstone bridge to field
The resistance shall be 1.691 to 1.725
ohms at an ambient temperature of 77°F
Megger between field leads and rotor frame
with a megohmmeter to measure the
resistance between the winding and frame.