If you ever cut open a PCV valve
02-03-2016, 12:15 PM
#41
Registered
So what exactly is the difference between running real pcvs to the intake and just hoses to the flame arrestor? I can see how pcvs have a strong vacuum actually sucking fumes out of the engine. What do the flame arrestor ones do? Just suck in what the engines push out? Doesn't seem like there's much sense to them.
Its positive crankcase ventilation. I've got no scientific research on this. Just my humble opinion. I think the PCV that is hooked to the base of a carb is much better then the vent to the F/A.. In a PCV system, with a vented oil filler cap it actually drawing air in the oil fill and through the motor creating a vacuum sucking up the fumes. The vent to the F/A system usually uses a non-vented oil fill and the vent to the F/A just pulls enough draw if fumes come out of the motor it will suck them through the F/A and into the motor to be burned.
Maybe you want the fumes to stay inside a boat motor and is why they use a vent system, I don't know. I personally like that the PCV is drawing new air through motor. Also I like that it don't suck blow by through my F/A. Another thing (again just my thinking) but with a slight PCV vacuum on the motor may prevent oil leaks.
