TM 10-3930-671-24 I. High Oil Consumption 1. Oil leaks Locate and repair. 2. Oil level maintained too high Maintain oil level between HIGH and LOW marks on dipstick. 3. Incorrect grade of oil used Use recommended type and SAE viscosity. 4. Clogged crankcase breather Check and clean thoroughly. 5. Oil pressure too high; relief valve stuck Clean, free-up valve, check spring tension. 6. Piston rings not properly run-in Break-in all new and rebuilt engines per recommendations. 7. Worn, broken, or stuck piston rings and Overhaul and re-ring with recommended service clogged oil control rings piston rings. 8. Worn pistons or cylinder bores Overhaul and rebuild engine, as required. 9. Worn bearings and valve guides Overhaul and replace, as required. 10. Worn or damaged intake valve seals Replace. J. Poor Fuel Economy 1. Operating with low coolant temperature Maintain (79 - 85°C) 175 - 185°F for maximum economy and performance. 2. Wrong fuel Use diesel fuel that meets specifications. 3. Loss of power Follow Item D. Recommendations. 4. Incorrect injection pump timing Follow recommended timing procedure. 5. Nozzles faulty Locate faulty injector; clean and test for pressure, leakage, and spray pattern. 6. Incorrect tappet clearance Adjust tappets per specifications. K. Sudden Stopping 1. No Fuel Refill fuel tank and bleed fuel system. 2. Restriction in fuel flow Clogged or dirty filters. Check lines for obstruction or break. 3. Air in fuel lines Bleed fuel system. 4. Transfer pump faulty Replace transfer pump. 5. Water in fuel Drain system and refill with clean fuel or strain fuel through chamois. 6. Internal engine seizure Turn engine manually. If unable to do so, check for foreign object in combustion chamber, or for piston or bearing seizure. 7. Faulty electrical shut-off on injection Repair or replace. pump F-71