Reduced oil pressure
Oil pressure at 5600 rpm less than 4.5 kgf/cm2. The pressure can be checked with a control pressure gauge screwed in instead of the low oil pressure warning light sensor.
Causes of malfunction and solutions:
- sticking of the oil pump pressure relief valve in the open position. Remove oil pump, disassemble and clean. Clean the valve from foreign particles and burrs;
- wear of crankshaft and camshaft bearings. Eliminate at a car service station.
Insufficient oil pressure at idle
Oil pressure at crankshaft speed 750...800 rpm less than 0.8 kgf/cm2, the oil pressure warning light is on.
Causes of malfunction and solutions:
- clogged oil pump relief valve. Remove the oil pump, disassemble the pressure reducing valve and clean it of foreign particles and burrs;
- oil pump gear wear. It is necessary to contact a service station to check and, if necessary, replace the oil pump or its gears;
- excessive wear on crankshaft or camshaft bearings. Oil escapes through enlarged gaps. At a service station, grind the crankshaft journals, replace the bearing shells. If necessary, replace the camshaft.
Increased oil consumption
Oil consumption during the period of running-in of parts decreases somewhat and after 2000... 3000 km of run it stabilizes and remains constant up to 50,000... 60,000 km, after which it gradually increases. Normal oil consumption should be no more than 35... 40 g per 100 km of the car. The cause of increased oil consumption is the wear of engine parts. Oil penetrates into the combustion chamber of the engine cylinders, burns there, increasing the exhaust smoke. In this case, you should contact a car service station to repair the engine.
Causes of malfunction and solutions:
- oil leaking through the seals. If an oil leak is visually observed, tighten the fasteners or replace the gasket;
- wear of piston rings, pistons or engine cylinders. It is necessary to repair the engine at a special auto center; replace worn parts;
- broken piston rings. Replace rings;
- coking of slots in oil scraper rings and grooves in piston grooves. Clean slots and grooves from soot;
- wear or damage to valve stem seals. Replace oil seals;
- wear of valve stems or guide bushings. Replace valves, repair cylinder head.
Increased oil pressure
Oil pressure over 4.5 kgf/cm2.
Causes of malfunction and solutions:
- high oil viscosity or the engine is not warmed up. Warm up the engine. Fill in the oil corresponding to the season of operation;
- pressure reducing valve sticking in the closed position. Remove the pump, disassemble, flush and clean the valve from foreign particles and burrs.