TM 1-1520-238-T-4 Change 5 6–109 6–45. HOD NGB 1 READING – DISPLAYS 28 LB OR LESS OIL PRESSURE 6–45 Tools: Nomenclature Part Number Tool Kit, Aircraft SC518099CLA01 Mechanic’s Tool Kit, Electrical SC518099CLA06 Repairer’s Adapter, Straight Pipe A1100-4-4 to Tube, Female Pipe End, 37 Flared Gage Pressure, Dial GGG76 Indicating (0-200 PSI) Multimeter, Digital AN/PSM-45 Personnel Required: 67R Attack Helicopter Repairer 68F Aircraft Electrician 152FG Pilot References: TM 1-1520-238-23 TM 1-1520-238-CL TM 9-1230-476-20-2 Equipment Conditions: Ref Condition TM 1-1520-238-23 Access provisions – L200 access panel and LN6, L60 fairings open WARNING Turn off power before detaching or attaching wires and connectors. High current 28 VDC or 115 VAC is present. Failure to do so could result in death or serious injury. 1. Visually inspect NGB 1 for low oil level and damage (TM 1-1520-238-23). Is damage present? YES Replace NGB 1 (TM 1-1520-238-23). NO Go to step 2. 2. Remove NGB 1 oil pressure transducer (TM 1-1520-238-23). Install pressure gage. Start engine 1 and place PWR lever to FLY (TM 1-1520-238-CL). Operate until readings stabilize. Is oil pressure above 28 LB on pressure gage? YES Go to step 3. NO Replace NGB 1 (TM 1-1520-238-23). 3. Check for open between: P673–85 and P673–84, P673–85 and P673–112 P673–85 and P673–113. Does open exist? YES Go to step 4. NO Go to step 5. 4. Check for open between: P61–L and P61–M, P61–L and P61–P, P61–L and P61–R. Does open exist? YES Replace NGB 1 oil pressure transducer (TM 1-1520-238-23). NO Repair open wire between: J61–L and P673–85, J61–M and P673–84, J61–P and P673–112, J61–R and P673–113. Go to paragraph 6–13. All data on pages 6–107 and 6–108 (paragraph 6–44) deleted