What is a PCV valve and how to check it?

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Anonymous

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What ist he function of the PCV valve and how can you check if it is working correctly or needs to be replaced?
 
As the name suggests it’s a pollution control valve (PCV) and it consist of a weight in a potted valve that is lifted by intake vacuum allowing crankcase gasses to be drawn off. To check one first remove it from the vacuum hose and valve cover, put it between your thumb and index finger and shake it. It should rattle. If not it may be gummed up so soak it in gasoline, while submerged pick it up between your thumb and index finger and shake it again, drain and repeat. If this doesn’t return the PCV to working condition, complete with rattle, you should replace it.
 
Given the price of a new valve? Why check it. Just go buy a new one. They should be replaced periodically anyway.

Pre-Crankcase Ventilator
Positive Crankcase Ventilator

Pulls blow-by gas out of the crankcase.

I was driving down the interstate a couple of years ago in my old truck. Piston pin slipped and wore a groove into the cylinder wall. Blow by was so severe that it blew the oil pan gasket. Draft tube was not enough.

PCV valve is necessary.
 
Positive Crankcase Ventilator

Any way to remove or update this? I hate the way it looks in my engine bay. Currently, I have no PCV in my valve cover.
 
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