If you don't pay attention to your engine oil, it can form resinous deposits and dirt inside the lubrication system. Over time, this can lead to clogging of the oil passages or the crankcase ventilation system. This can increase crankcase pressure, resulting in increased crankcase gas volume. Excessive crankcase gases, combined with damaged ignition system components, can cause engine misfires that are difficult to detect.
Deterioration of oil quality during engine operation occurs due to its dilution by fuel, contamination by mechanical impurities and oxidation, as well as due to the activation of additives that give the oil better properties.
Dilution of the lubricant by fuel leads to increased wear of engine parts. Fuel gets into the engine crankcase when the cylinder-piston group is significantly worn, or when the spark plug or injector is not working.
Coolant may enter the lubrication system as a result of a leak in the cylinder head gasket.
During maintenance, check the fastenings of oil lines and lubrication system parts. If any fasteners become loose, tighten the nuts and bolts
Check for oil leaks in the following areas:
- Oil pan.
- Oil pan drain plug.
- Oil pressure warning light switch.
- Oil filter.
- Oil radiator.
- Intake valve phase control device cover and intake valve phase control solenoid valve.
- Mating surfaces of the cylinder block and cylinder head.
- Mating surfaces of the cylinder head and valve cover.
- Mating surfaces of the front and rear parts of the camshaft drive chain housing.
- The mating surfaces of the rear part of the camshaft drive chain housing and the cylinder block.
[Information copied from the website: nissanbook.ru]
Change the oil in the engine crankcase. The oil is drained from the heated engine. After draining the used oil, it is recommended to flush the system using a special installation and flushing oil. You can also flush with low-viscosity spindle oil, a mixture of oil and diesel fuel, or a flushing fluid consisting of 90% white spirit and 10% acetone. To do this, pour half the lubrication system's capacity of flushing fluid into the crankcase, start the engine, and let it run for 4-5 minutes at high speed (800-1000 rpm) idle, then drain the flushing fluid and add fresh oil.