General information about the engine lubrication system (Mazda 3 BK)

The lubrication system operates under pressure, the oil passes through the oil filter. Mazda engines are equipped with an environmentally friendly oil filter with a replaceable filter element. The lubrication system has a full-flow oil cleaning system and oil supply under pressure to the main moving parts and units of the engine. The system consists of an oil sump, a gear oil pump with an oil receiver, a full-flow mesh oil filter, an oil pressure sensor and oil valves. The oil pump takes oil from the engine oil pan and supplies it to the oil filter. There is a bypass valve on the discharge side of the oil pump. If the oil pressure is too high, the valve opens and some of the oil flows back into the engine oil pan. Clean oil enters the main oil line through the middle of the filter element of the oil filter. If the filter is clogged, the bypass valve located in the oil filter housing supplies unfiltered oil directly to the main oil line. The oil filter pipe contains a check valve that prevents the oil channels and hydraulic tappets of the engine valves from emptying. The main oil line has channels for lubricating the crankshaft bearings. Through inclined holes in the crankshaft, oil is supplied to the connecting rod bearings, and from there it is sprayed onto the piston pins and cylinders. At the same time, oil is supplied to the cylinder head through the ascending channels and provides lubrication of the camshaft bearings and operation of the hydraulic tappets.

The oil pan is made of multilayer steel with a high damping coefficient. The LF and L3 engines also have a water-cooled oil cooler.

Fig. 2.38. Working components of the Mazda 3 car lubrication system: 1 – chain tensioner spring; 2 – chain tensioner; 3 – oil pump; 4 – chain guide; 5 – oil pump chain; 6 – oil pump sprocket; 7 – oil pan; 8 – mesh oil filter; 9 – gasket; 10 – oil spray nozzle valve; 11 – Oil filter adapter; 12 – oil pressure sensor; 13 – oil filter; 14 – oil filter cover; 15 – oil filter drain plug; 16 – sealing ring; 17 – LF and L3 model engines; 18 – oil cooler

Caution! On vehicles equipped with engines with a catalytic converter, it is necessary to ensure that the oil level on the dipstick is not above the maximum mark. If too much oil has been poured into a vehicle with a catalytic converter, the excess oil must be removed from the crankcase by draining or sucking it out (with a special vacuum pump), otherwise unburned oil will enter the exhaust system and may destroy the catalytic converter.

Fig. 2.39. Lubrication systems of L8 and LF engines: 1 – camshaft; 2 – cylinder head; 3 – cylinder block; 4 – oil spray nozzle valve; 5 – crankshaft; 6 – oil filter; 7 – oil filter bypass valve; 8 – oil pump; 9 – mesh oil filter; 10 – oil pan; 11 – drained oil; 12 – chain tensioner; 13 – LF model engine; 14 – oil cooler; 15 – to the oil filter; 16 – from the oil pump; 17 – oil pressure sensor; 18 – hole; 19 – piston; 20 – main bearing; 21 – crankshaft bearing, connecting rod bearing; 22 – safety valve; 23 – vertical projection; 24 – side view

Fig. 2.40. Lubrication systems of L3 engines: 1 – camshaft; 2 – cylinder head; 3 – cylinder block; 4 – oil spray nozzle valve; 5 – crankshaft; 6 – oil filter; 7 – oil filter bypass valve; 8 – oil pump; 9 – mesh oil filter; 10 – oil pan; 11 – drained oil; 12 – chain tensioner; 13 – oil cooler; 14 – oil pressure sensor; 15 – hole; 16 – piston; 17 – main bearing; 18 – crankshaft bearing, connecting rod bearing; 19 – safety valve; 20 – vertical projection; 21 – side view; 22 – balancing shaft; 23 – Oil control valve (OCV); 24 – actuator for changing valve timing; 25 – oil filter (inner Front Engine Cover)