What is a four stroke engine

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Answered by: Anne Srinivas.

  • Jul 14th, 2006

A 4-s engine is that in which for every four revolutions of crank one power stroke is produced.  

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  • Jul 8th, 2006

A four stroke engine is that which produces mechanical power from the chemical energy available in the form of fuel.


  • Jul 10th, 2006

The four strokes means four stages of combustion including compression and expansion of the piston of the engine.

Anne Srinivas.

  • Jul 14th, 2006

A 4-s engine is that in which for every four revolutions of crank one power stroke is produced.  


  • Jul 20th, 2006

A four stroke engine is defined as that in two cycles and four strokes such that suction compression expansion and exhaust will occur to produce one power stroke is known as four stroke.

zaheer hussain

  • Jul 31st, 2006

 The 4s engine is nothing but it has two valves one is inlet and another is exhaust. the stroke will be done one by one like first suction,compression,power and exhaust, and for every four stroke there will be one power.this is four stroke engine

mithun shah

  • Aug 1st, 2006

when one  autocycle is completed in two revolutions of crankshaft the engine is known as four stroke engine.

ramanasreenivas burela

  • Aug 13th, 2006

an engine in which the different processes called(inhaling the charge,compressing it,burningit,exhausting itoutside)are performed in engine cylinder where piston travels from one dead center to another deadcenter 4 times .


  • Aug 22nd, 2006

in four stroke engine,the power is produced after the two rotation of crankshaft.


  • Sep 5th, 2006

The Working Cycle is completed by the complete two revolution of crankshaft is called as 4-stroke engine...


  • Sep 21st, 2006

it has four strokes



3.power or expanstion



  • Oct 5th, 2006

A four stroke engine is a power producing device which produces a power stroke for 4 strokes they are






  • Feb 5th, 2007

A completed operation of an engine that is Suctionstroke. compression stroke, expansion stroke and exhaust stroke is completed by the single rotaition of the crank shaft. Generally in a four stroke engine suction and compression takes at the first 180" degree of the rotation fo the crank shat and the expansion and exhasut stroke held at the remaining 180"degree of the crank rotaion. so by the complete rotation of 360"degree of a crank shaft all the four operation are completed, and hence it is called as four stroke engine


  • Feb 18th, 2007

in a 4 stroke engine, there occurs 2 revolutions or 4 strokes like suction expansion compression and exhaust . we get 1 power stroke per cycle() . piston reciprocates 4 times from tdc to bdc .


  • Feb 23rd, 2007

four stroke engine work on otto cycle.in this engine four process are done.1.suction2.compression3.power4.exhaust.at the time of 1st stroke fuel will enter in to cylinder.entered fuel compressed by the piston from bottom dead center to top dead center.at tdc spark plug ignited to make power stroke to movw piston from tdc to bdc.at the time of exhaust stroke waste air move out by moving piston from bdc to tdc.


  • Jul 31st, 2007

4-stroke engine can be defined as a type of engine by which we get a power stroke in every two revolutions of the crank shaft.
while in 2-stroke, we get a power stroke in each revolutions of the crank shaft.

ashwini pratap singh

  • Oct 18th, 2007

Four stroks means sunction, compression, expension, exaust in one cycle.

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In case of four stroke engine their are four event
1. Suction
2. Compression
3. Power
4. Exhaust

This four event are completed in within four moment of piston and one power stroke is obtain two(2) Revolution of crank shaft, i.e=(720degree)  hence it is called  as Four stroke engine.

2. Four stroke engine has less pick-up but torque is high.
3. Four stroke engine are available at two form 1.  Petrol 2. Diesel 
4. In case of Four stroke petrol engine there are  2 valves are used for suction & exhaust.
5. But in case of Four stroke diesel engine there are port are used  for suction & exhaust.


  • Aug 20th, 2010

Four stroke engine is an engine in which 1 cycle=4 rotations or strokes of crank.
The combustion process takes place in 4 stages/parts/strokes.
1st stage-Suction
2nd stage-compression
3rd stage-Combustion & expansion
4th stage-exhaust

4 stroke engines are more fuel efficient as compared to 2 stroke engines but the thermal efficiency of 2 stroke engine is greater than that of 4 stroke engines.

Both diesel & petrol engines are now-a-days available in 4 stroke type.
Power produced per cycle by a 4 stroke engine is lesser than that of 2 stroke engine.


  • Jul 16th, 2011

which fuel is burned with in the engine proper stroke of 4stroke engine




4.power stroke

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  • Jul 17th, 2011

A 4 stroke engine works under suction,compression,power and exhaust strokes.here the crank shaft completes 2 revolutions to produce one power stroke.

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rajat singh shishodia

  • Jan 22nd, 2016

4 stoke engine firing order is 1-3-4-2...... 4 stoke engine is when piston moves from TDS to BDS then suction stroke after that when it goes from BDS to TDS then air is compressed and fuel is inject after which blast occur and piston moves from TDS to BDS having increases in temp almost 2500 degree Celsius which is known as power stroke and after that last it moves from BDS to TDS and energy is exhaust means exhaust stroke.

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  • Jan 31st, 2016

A four-stroke engine (also known as four cycle) is an internal combustion (IC) engine in which the piston completes four separate strokes while turning a crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either direction.

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  • Feb 22nd, 2017

Four stroke engine engine consists of four strokes namely:
Suction Stroke
Compression Stroke
Power Stroke and
Exhaust Stroke

For every four strokes there are two revolutions of crank and one power stroke is produced.

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  • Sep 9th, 2017

There are four stroke in petrol engine

When the engine starts, the piston descends to the cylinders bottom from the top. Thus, the pressure inside the cylinder reduces. Simultaneously the intake valve opens and the air-fuel mixture enters the cylinder.

In compression stroke both the valves are closed and charge is compressed as the piston moves from bdc to tdc. As a result of compression, the pressure and temperature of charge increases to high value.

Very shortly when the piston reaches TDC during the compression stroke the air fuel mixture is ignited by the spark plug. It suddenly increases the pressure and temperature of the product of combustion.

Due to the rise in pressure the piston is moved down with great force and hot gases expand. Thus, work is done on the piston by the flue gases and some of the heat is converted into mechanical work during this process

As piston moves from BDC to TDC, the exhaust valve opens and piston pushes out the product of combustion from the engine cylinder to atmosphere. This complete the cycle and engine cylinder is again ready to suck the charge.

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  • Oct 6th, 2017

Piston moves from top dead centre to bottom dead centre is known as a stroke its take half revolution of crank shaft. In a four stroke engine we get the energy on power stroke. Its complete two revolutions of crank shaft. The four strokes are suction, compression, power, exhaust.

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  • Jan 26th, 2018

Four stroke means suction stroke, compression stroke, ignition stroke, exhaust stroke of an engine.

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