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 following function.
The compression ring prevents leakage of pressure in the cylinder from the piston circumference.
The oil ring clears off extra engine oil adhered to the cylinder wall.
The piston ring transmits piston heat to the cylinder wall to cool the piston.
Piston pin
The reciprocating movement of the piston is transmitted to the connecting rod by the connection of the piston pin to connecting rod.
Construction
Piston
The high-temperature strength piston is made of aluminum alloy with excellent thermal conductivity.
The piston has a cavity on the top surface. As a result, the initial combustion flame is prevented from hitting the top surface of the piston to reduce cooling loss.


The sliding resistance has been reduced by optimizing the piston skirt shape.
A weight reduction is realized by optimizing the piston shape.
With the adoption of the offset piston, piston slap is suppressed.

Piston ring
A barrel-face ring for the top ring and a taper under cut ring for the second ring have been adopted.
A three-piece oil ring consisting of a side rail and spacer have been adopted for the oil ring.
Tracking capability to the cylinder wall has been improved by thinning down the piston ring. As a result, a low-tension piston ring has been implemented without increasing the engine oil consumption, and the sliding resistance has been reduced during reciprocating movement.
Piston pin
The piston is a full-floating type.
Connecting Rod, Connecting Rod BearingHeated Oxygen Sensor (HO2 S)
Purpose/Function
Detects the oxygen concentration (theoretical air/fuel ratio) in the exhaust
gas as basic information for mainly determining the fuel injection amount and
as information for determining the deterioration of catalytic converter.
Detects the oxygen concentration ( ...
Accessory Sockets
Only use genuine Mazda accessories or the equivalent requiring no greater than
120 W (DC 12 V, 10 A).
Front
The ignition must be switched to ACC or ON.
Center, Rear
The accessory sockets can be used regardless of whether the ignition is on or
off.
CAUTION
●To prevent accessory ...
Rear Window Defroster
The rear window defroster clears frost, fog, and thin ice from the rear window.
The ignition must be switched ON.
Press the switch to turn on the rear window defroster. The rear window defroster
operates for about 15 minutes and turns off automatically.
The indicator light illuminates during op ...