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 MountsSae Standards
In accordance with new regulations, SAE (Society of Automotive Engineers)
standard names and abbreviations are now used in this manual. The table below
lists the names and abbreviations that have been used in Mazda manuals up to
now and their SAE equivalents.
...
Air Intake Actuator [Full Auto Air Conditioner]
Purpose
The air intake actuator moves the air intake door in the blower unit to switch
the air intake port.
Function
The air intake actuator drives the motor based on the signal from the climate
control unit and moves the air intake door to the FRESH or REC position.
...
Cruise Main Indicator Light (Amber)
Purpose/Function
Illuminates while the cruise control system is in standby mode to inform
the driver that the cruise control system is on standby.
Construction
Built into the instrument cluster.
Operation
Illuminates while the cruise control system is on sta ...