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Crankcase Ventilation System



CRANKCASE VENTILATION SYSTEM DESCRIPTION

The compressed combustion gas which escapes past the piston rings into the crankcase is known as blow-by gas. Blow-by gas contains large amounts of carbon monoxide (CO) and hydocarbon (HC). The positive crankcase ventilation (PCV) system prevents the blow-by gas from being emitted into the atmosphere. The PCV system routes the crankcase blow-by gas back into the intake system where the blow-by gas becomes part of the combustion process.

Results Of Incorrect Operation
A plugged oil separator or hose may cause any of the following conditions:
- A rough engine idle
- Engine stalling or low engine idle speed
- High engine crankcase pressure
- Engine oil leaks
- Engine oil in the air cleaner
- Oil sludge in the engine
- Engine oil consumption
- Excessive exhaust emissions

A faulty separator or hose may cause any of the following conditions:
- A rough engine idle
- Engine stalling
- High engine idle speed
- Incorrect engine crankcase pressure
- Excessive exhaust emissions
- Engine oil consumption