Describe the working of PCV System.

Describe the working of PCV System.
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Answer :

Working of PCV system: 

During normal compression stroke, a small amount of gases in the combustion chamber escapes past the piston. Approximately 70 % of these ‘blow-by’ gases are unburned fuel (HC) that can dilute and contaminate the engine oil, cause corrosion to critical parts, and contribute to sludge build up. At higher engine speeds, blow-by gases increase crankcase pressure that can cause oil leakage from sealed engine surfaces. The purpose of PCV system is to remove these harmful gases from the crankcase before damage occurs and combine them with the engine’s normal incoming air: fuel mixture. PCV system uses a variable flow PCV valve accurately matches ventilation flow with blow-by production characteristics. By accurately matching these two factors, crankcase ventilation performance is optimized, while engine performance and drivability remains unaffected. 

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