Contents: Low oil pressure ↓ Insufficient oil pressure at engine…↓ Increased oil consumption ↓ High oil pressure ↓
Low oil pressure
Oil pressure at 5600 rpm is less than 4.5 kgf/cm². The pressure can be checked with a control pressure gauge screwed in place of the low oil pressure indicator lamp sensor.
Causes of malfunction and methods of elimination:
- the oil pump pressure relief valve is stuck in the open position. Remove the oil pump, disassemble and clean. Clean the valve from foreign particles and burrs;
- wear of crankshaft and camshaft bearings. Eliminate at a vehicle service station.
Insufficient oil pressure at engine idle
The oil pressure at a crankshaft speed of 750...800 rpm is less than 0.8 kgf/cm², the oil pressure indicator lamp is on.
Causes of malfunction and methods of elimination:
- clogging of the oil pump pressure relief valve. Remove the oil pump, disassemble the pressure relief valve and clean it from foreign particles and burrs;
- wear of the oil pump gears. It is necessary to contact the service station to check and, if necessary, replace the oil pump or its gears;
- excessive wear of the crankshaft or camshaft bearings. Oil is leaking through increased 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 running-in period of parts decreases slightly and after 2000...3000 km of run 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's run. The reason for increased oil consumption is wear of engine parts. Oil penetrates into the combustion chamber of the engine cylinders, burns there, increasing the smoke of the exhaust. In this case, you should contact a car service station for engine repair.
Causes of malfunction and methods of elimination:
- oil leaks through sealing gaskets. If oil leaks are 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 specialized auto center; replace worn parts;
- piston ring failure. Replace rings;
- coking of the slots in the oil scraper rings and grooves in the piston grooves. Clean the slots and grooves from carbon deposits;
- wear or damage to valve stem seals. Replace stem seals;
- valve stems or guide bushings are worn. Replace valves, repair cylinder head.
High oil pressure
Oil pressure is more than 4.5 kgf/cm².
Causes of malfunction and methods of elimination:
- increased oil viscosity or engine not warmed up. Warm up the engine. Fill with oil appropriate for the season of operation;
- the pressure reducing valve is stuck in the closed position. Remove the pump, disassemble, wash and clean the valve from foreign particles and burrs.
(The text is published on the portal: VAZbook.ru)