Purpose, Function
The crankshaft converts the reciprocating movement of the piston to a rotational movement via the connecting rod.
The main bearing forms an oil film on the outer surface of the crankshaft journal to prevent wear due to sliding.
Construction
Crankshaft
The crankshaft is installed to the inside (crankcase) of the cylinder block.

The crankshaft has a key groove to match timing to the crankshaft pulley.
The crankshaft has the following parts shown in the figure.

The optimized shaft diameter ratio of the crankshaft journal and crank pin has reduced sliding resistance while maintaining rigidity.
The steel crankshaft has five bearings and eight counterweights for improved accuracy in the rotational balance.
The crankshaft journal and crank pin have been induction hardened* to bear high loads.
The crankshaft has an oil passage for supplying engine oil to the crankshaft journal and crank pin.

Main bearing
The main bearing is installed to the outer surface of the crankshaft journal.
The upper main bearing and lower main bearing are made of aluminum alloy.
The upper main bearing has an oil groove and oil hole.
Thrust force is suppressed by the thrust bearings on both sides of the No.3 journal.

Crankshaft Position (CKP) Sensor
Motor MountsFuel Injection Control System
Outline
Performs optimum fuel injection according to engine operation conditions.
The PCM determines the engine operation conditions based on the signals from
each input device and drives the fuel injectors at the optimal fuel injection
time (fuel injection amount) and the fuel ...
Positive Crankcase Ventilation (PCV) Valve Inspection
Airflow Inspection
1. Disconnect the section (A) of ventilation hose shown in the figure.
2. Start the engine and verify that vacuum is applied to the end of the disconnected
ventilation hose while the engine is idling.
If vacuum is not applied to the ventilation hose, perform the p ...
Piston, Piston Ring, Piston Pin
Purpose, Function
Piston
The piston in the cylinder of the cylinder block moves reciprocally by the
pressure received when the air-fuel mixture combusts.
Piston ring
The piston ring consists of the compression ring (top ring, second ring)
and the oil ring, and has the foll ...