TM 10-3930-664-24 14.  Mount rotor (20) in test stand as shown in figure. Using  dial  indicator, conduct true-running test at the following points: - OD of rotor (20) - OD of collector rings (27) Maximum error for rotor (20) is 0.05 mm. Maximum error for collector rings (27) is 0.03 mm. 15.  Remove rotor (20) from test stand. 16.  Remove and discard O-ring (25).  Using bearing puller, remove bearing (26) from rotor (20). 17.  Unsolder leads of excitation winding from collector rings (27).  Using bearing puller, remove collector rings from rotor (20). C. CLEANING Clean alternator components in accordance with para- graph 1-24. D. INSPECTION 1. Inspect alternator components in accordance with paragraph 1-24. 2. Inspect carbon brushes on transistor regulator (1) for obvious damage.  Brushes shall project 0.27 inches (minimum). E. RFPAIR CAUTION Do not allow solder to contact brushes. 1. If brush set is damaged or brushes project less than 0.27 inches, unsolder brush set and replace.  New brushes shall project 0.39 inches.  Check  brushes for  freedom  of movement after installation. 2. Repair of the alternator consists of removal and replacement of defective, deformed, or damaged components. 3-92