Toro 303447 - Power and Exhaust Strokes

POWERstroke:thisisthestartofthesecondrevolutionof
theengine.WhilethepistonisclosetoTopDeadCenter,
thecompressedair–fuelmixtureinagasolineengineis
ignited,usuallybyasparkplug,orfuelisinjectedintothe
dieselengine,whichignitesduetotheheatgeneratedin
theairduringthecompressionstroke.Theresulting
massivepressurefromthecombustionofthecompressed
fuel‐airmixtureforcesthepistonbackdowntoward
bott omdeadcenter.
Detail
PistonmovesfromTDCtoBDC
Intakevalveclosed
Exhaustvalveclosed
Rapidburningcausesrapidriseintemperature.
Rapidriseintemperaturecausesincreasedpressure.
Pressureinducesaforceonthepiston.
Forceonpistonproducestorqueoncrankshaft.
540degreesrotation
EXHAUSTstroke:duringtheexhauststroke,thepiston
onceagainreturnstotopdeadcenterwhiletheexhaust
valveisopen.Thisactionevacuatestheburntproductsof
combustionfromthecylinderbyexpellingthespentfuel‐
airmixtureoutthroughtheexhaustvalve(s).
Detail
PistonmovingfromBDCto
TDC.
Intakevalveclosed
Exhaustvalveopen
Wastegassesareexpelledfromthecylinder.
720degreesofrotation