Operation & Maintenance Manual for WP7 Euro Ⅵ Vehicle Diesel Engine 3.7 Unstable speed 3.8 Low oil pressure 15 Causes Troubleshooting 1. Poor quality fuel, containing too much water or wax Clean the fuel system and replace the fuel 2. Air comes into the fuel suction pipe Check the tightness of fuel pipes and the joints; release the air 3. Governor weight and spring do not work normally Check and repair (by specialized operator) 4. Uneven fuel supply Check and adjust (by specialized operator) 5. Poor atomization of the injector nozzle Check and repair 6. The turbocharger surges Check the compressor flow passage and remove the blockage, remove the carbon deposit in the exhaust path 7.
Turbocharger bearing is broken Replace Causes Troubleshooting 1. Low oil level in the oil sump or lack of oil Check the oil level and leakage; repair and add oil 2. Failure of pressure regulator in the main oil passage Check, clean and repair the valve 3. Oil strainer, oil pipe, joint gaskets are blocked or broken Check the oil strainer and joints, repair the casting shrinkage porosity if any 4. Unqualified oil grade Replace with qualified grade 5. Oil inlet pipe of the engine oil pump leaks Examine the oil pipe, joints; repair or replace 6.
The temperature of water in cooling system is too high, and temperature of lubricating oil is too high Check the working conditions of cooling system, and correct 7. The resistance of oil filter is too big Replace with a new element 8. Oil cooler is blocked Check and remove the blockage 9. The main oil passage is blocked Check and remove the blockage 10. Excessive bearing clearance or the bearing is damaged Check and repair 11. Excessive wear of parts, overhaul is required Check the working hours of the engine and carry out an overhaul