TM 10-3930-669-34 VERIFY REPAIR (1) Start engine (TM 10-3930-669-10). (a) If  exhaust  smoke  is  excessive  and black   or   gray   in   color,   fault   not corrected.    Perform  Step  (2)  below and notify supervisor. (b) If    exhaust    smoke    is    normal    in quantity  and  color,  fault  has  been corrected (2) Shut down engine. 2-47