TM 55-1520-240-T 4-8.1 ENGINE PERFORMANCE CHECK OPERATIONAL CHECK (Continued) 4-8.1 TASK RESULT 1. Follow procedures in TM 55-1520-240-10 as pilot If ENG 1 FAIL or ENG 2 FAIL warning does not come on, starts engines: go to task 4-8.2. A.  DECU BIT TEST.  Check following occurs: If ENG 1 FAIL or ENG 2 FAIL warning does not go out, go ENG FAIL warning comes on after ENG PRI REV switch to task 4-8.3. set to PRI and goes out about 12 seconds later. If DECU No. 1 or No. 2 display (1) is blank or another DECU No. 1 and No. 2 displays (1) read 88. code shown, refer to task 4-12.4. B.  FIRST ENGINE START: Check engine instruments (2 If engine does not motor, go to task 4-10.4. through 5) when stabilized at ground idle (N1 at 50 to If engine motors normally but does not start, go to task 59%). 4-10.4. If engine oil pressure gauge (2) does not indicate oil pressure, go to task 8-3.3. If engine oil pressure is below 20 psi, go to task 8-3.3. If N1 gauge (3) does not indicate between  50 and 59 percent rpm after 45 seconds, go to TM 1-2840-265-23. If ENG TEMP gauge (4) does not indicate temperature, go to task 8-5.3. If ENG TEMP indication is high  or hot start occurs, go to TM 1-2840-265-23. CAUTION If the No. 1 engine is started first, the No. 2 engine N2 section starts turning.  The en- gine lubrication system is driven by the N1 section which does not turn until the START sequence is initiated.  Delay in start- ing the No. 2 engine will result in excessive wear on N2 bearing package and seals. Start the No. 2 engine within 3 minutes after the first engine started. TASK RESULT C. SECOND ENGINE START: Check engine instrument If engine does not motor, go to task 4-10.4. display when stabilized at ground idle (N1 at 50 to 59%). If engine motors normally but does not start, go to task 4-10.4. If engine oil pressure gauge (2) does not indicate oil pressure, go to task 8-3.3. If engine oil pressure is below 20 psi, go to task 8-3.3. If N1 gauge (3) does not indicate between  50 and 59 percent rpm after 45 seconds, go to TM 1-2840-265-23. If ENG TEMP gauge (4) does not indicate temperature, go to task 8-5.3. If ENG TEMP indication is high or hot start occurs, go to TM 1-2840-265-23. D. ENGINE CONDITION LEVERS - FLY.  Check engine If either NO. 1 or NO. 2 engine oil pressure gauges (5) instruments display. fluctuate more than 5 psi, go to task 8-3.3. If either NO. 1 or NO. 2 engine oil temperature gauge (5) is high, go to TM 1-2840-265-23. E. DECU FAULT MONITORING: DECU No. 1 and No. 2 If DECU No. 1 or No. 2 display (1) is blank or another displays (1) read 88. code shown, refer to task 4-12.4. F. BEFORE TAXI- FADEC SYSTEM REVERSIONARY If FADEC reversionary mode is inoperative, go to task TEST: Observe torquemeter (6) gauge. 4-8.4.  If FADEC toggles between primary and reversion- ary modes, go to task 4-8.6.  If torques are not matched when switch is at PRI, go to task 4-8.7. G. BEFORE HOVER - POWER ASSURANCE TEST: If DECU display is F, go to task 4-8.5. Observe DECU No. 1 and No. 2 displays (1). 2. If pilot performs engine overspeed test and test results are not satisfactory, go to task 4-8.8. FOLLOW-ON MAINTENANCE: TM 55-1520-240-23: Hydraulic power off. Electrical power off. Battery disconnected. END OF TASK Change 17  4-197