What is the Vent Oil Seperator all about?

An internal combustion engine runs on a series of controlled explosions. During this process, gases are created. While most of those gases will eventually make their way from the combustion chamber through the exhaust manifold and out the muffler, some pass the pistons into the crankcase. The latter is called “blow-by”, and it can be very damaging to an engine. It creates additional pressure within the crankcase that damages seals and gaskets. To combat this deleterious effect, a ventilation system is used.

These systems require several different components in order to operate, including the positive crankcase ventilation (PCV) valve and the vent oil separator hose. The vent oil separator hose is responsible for capturing and collecting oil droplets that invariably accompany those spent gases and ensuring they are not released into the combustion chamber. The gases are then re-burned for emissions control. If your vent oil separator is plugged, excess pressure can build up inside the crankcase and blow out a seal, causing an oil leak. Excess oil in the vent oil separator can also enter the combustion chamber, causing a misfire and rough run with blue, oily exhaust.

Keep in mind:

• The vent oil separator hose is susceptible to clogging, particularly during cold weather.
• The vent oil separator hose is part of the crankcase ventilation system. If you’re experiencing related problems, have the entire system diagnosed.

How it's done:

• The faulty vent oil separator is located and identified
• The intake is removed and the vent oil separator is removed
• The new vent oil separator is installed and the intake is installed
• The engine is started and idled, then the new vent oil separator is checked for leaks
• The vehicle is road tested and checked for proper operation

Our recommendation:

The vent oil separator doesn’t have a set maintenance schedule. If you are having symptoms related to the vent oil separator, have one of our expert mechanics diagnose the crankcase ventilation system on your vehicle and repair it as necessary.

What common symptoms indicate you may need to replace the Vent Oil Seperator?

• Oil is present in the PCV valve
• Blue smoke from the exhaust
• Engine runs rough with a check engine light on

How important is this service?

The crankcase ventilation system is a vital part of your emissions control system and can adversely affect engine operation if it is not maintained properly.