That’s the breather mounted on the valve cover. Don’t know if that was considered a pcv system or not. In the 50s, they just had a pipe connected to it exhausting to the open air. When the mesh inside got too oil filled, mechanics would just burn the oil off.
So it’s like a vent for the crank-case/valve cover area? No path for fresh air to flow through, but it just vents out. Seems like that would work pretty good up to 100 K miles or so. Maybe why cars of that era’s odometers only had 5 digits.
That 70s part had to be connected to the intake, not just a vent.
It was/is part of the PCV system.
Green circle= breather w/filter element, not screen, connected to air filter housing. Allows somewhat filtered air into crankcase via pass. side valve cover.
Yellow circle= PCV valve w/vacuum hose to carburetor to draw air out via driver side valve cover.
Interesting. What do you mean by air going into crankcase is “somewhat filtered”? Is it filtered by the engine air filter? Does the PCV valve attach to that hose & stick into a grommet in the driver’s side valve cover?
The filter element isn’t much.
Yes, if you blow up that pic you can just see the Valve but here’s a better picture, different engine same concept.
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That sure looks like a pcv valve on the second picture but I just don’t remember what was on my 74 olds. Our 58 just vented to the ground, so big differences in what happened over ten plus years.
Your Ford should be the same design, PCV valve on the right valve cover and the breather on the left. Remove the air cleaner lid and you should see the breather filter.
The breather hose is connected to the oil cap.
I remember replacing a fair number of those Ford filters, but not the GM ones while working at a garage in the ‘70s. Maybe because the Ford one was immediately visible when you took off the air filter cover, and was typically pretty oily. The GM was ‘out of sight out of mind’.
My old cars just had a tube going from the valve gallery or crankcase to the air intake filter housing.
That tube was for intake air to the crankcase. There had to be a second tube from the engine to the intake system.
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