Working of four stroke cycle in petrol engine.
(i) Induction stroke
- Piston moves downwards creating a partial vacuum on the upper part of the cylinder.
-The partial vacuum causes the inlet valve to open.
- The open inlet valve sucks in fuel and air into the cylinder.
- The exhaust valve remains closed.
(ii) Compression stroke
- The inlet and exhaust valve are closed.
- The piston moves up the cylinder.
-The air fuel mixture is compressed in the upper part of the cylinder.
(iii) Power stroke
-The piston reaches the upper most portion of the cylinder.
- At this point the air fuel mixture is fully compressed.
- The spark plug produces a spark igniting the fuel air mixture.
- The ignited mixture expands, generating pressure that forces the piston downwards thus generating power.
- The inlet and outlet valve remain closed.
(iv) Exhaust stroke
- The exhaust valve opens the inlet valve remains closed.
- The piston moves up the cylinder or forces out the exhaust gases.
john3 answered the question on December 15, 2017 at 14:38
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