TM-9-2815-200-35 Maintenance Manual for AVDS-1790-2M AVDS-1790-2A and AVDS-1790-2AM Engines Download
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Malfunction 3. No engine oil pressure. 4. High engine oil tem- perature. 5. Excessive oil consumption. 3-10. Troubleshooting Cooling System 1. Cooling fans not operating. 2, Cooling fam operate but engine does not cool. Probable Cause c. Improper grade of oil for prevailing ambient temperatures. d. Obstructed crankcase oil passages. a. Low oil level. b. Oil pressure sending unit not functioning properly. c. Obstructed crankcase oil passages. d. Oil pressure regulator valve not functioning properly. e. Oil pump or drive gears failed. a. b. c. d. e. Restricted air flow through oil coolers. Oil temperature sending unit not functioning properly. High oil temperature warning light sending switch not functioning properly ). Oil cooler thermostatic bypass valve not functioning properly. Restricted engine oil cooler. f. Cooling fan clutch slipping or inoperative. Engine runs hot. g. Excessive fuel, engine runs hot. h. Defective pieton cooling nozzles. a. High oil temperature or oil leaks. b. Improper grade oil for prevailing ‘ temperature. c. Restricted crankcase breather system. d. Worn or scored pistons, cylinders, or rings. e. Worn valve stems or valve guides. f. Worn or leaking turbosup- ercharger oil scale. a. Fan drive clutch slipping or inoperative. b. Fan drive gear train not func- tioning. a. Oil cooler thermostatic bypass valve not functioning properly. b. Defective oil cooler bypass valve. Corrective Action c. Drain crankcase oil and fill with proper grade oil. Refer to pertinent vehicle Technical Manual, Appendix A. d. Refer to 1h, above, for corrective action. a. Fill oil pan to proper level Refer to per- tinent vehicle Technical Manual, Appendix A for proper grade oil for prevailing tem- perature. b. Refer to 1 d, above, for corrective action. c. Refer to 1 h, above, for corrective action. d. Refer to 1 f, above, for corrective action. e. Refer to 1 k, above, for corrective action. a. Remove oil cooler air restrictions or replace damaged screens, deflectors, and baffles (tables 5-2 and 5-7 ). b. Replace aending unit (tables 5-10 and 7-3). c. Replace switch (tables 5-10 and 7-3). d. Replace valve ( para 6-38). e. Remove engine oil cooler (table 5-2). Clean and repair oil cooler (table 6-3 7). Install oil cooler (table 7-1 2). f. Refer to para 3-10 for corrective action. g. Refer to fuel system troubleshooting, para 3-8, for corrective action. h. Remove oil pan (table 4-5). Inspect pump and nozzle. Replace defective parts. Install oil pan (table 4-5). a. Refer to 4, above, for corrective action. Repair oil leaks. b. Refer to pertinent vehicle Technical Manual, Appendix A, for proper grade for prevailing temperature. c. Remove (table 5-5), clean (para 6-2) and install (para 7-9) breather tubes d. Refer to para 3-8, 4e. e. Remove cylinders and replace defective parts. Assemble cylinders. f. Refer to para 3-7, 1c for corrective action. a. Rebuild front fan drive clutch (table 6-24). Rebuild rear fan drive clutch (table 6-24). b. Disassemble engine (chapter 5). Replace damaged parts. Assemble engine (chapter 7). a. Refer to 4d, above. b. Replace valve (table 6-37). 3-10