Breather to air cleaner

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Ohio66Cuda

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I was thinking of changing current air cleaner to something newer (chromed?). What to do with the connection to the air breather on the valve cover?

Do I need that connection?

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Most aftermarket air cleaners have a knockout provision on the base to have a breather hose hook up.
 
That only supplies air* to the PCV breather. you can run a hose to the base of the new cleaner with a 90 fitting or install a breather with a filter on it. (* edited) It more likely supplies the low pressure air cleaner environment crankcase vapors to re-burn through the air filter. Evicence would be a possible discoloration on your element at that spot.
 
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pishta said:
That only supplies filtered air to the PCV breather. you can run a hose to the base of the new cleaner with a 90 fitting or install a breather with a filter on it.
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I like the filtered breather if you are going non stock.

where the OEM hose attached to the OEM filter housing is actually outside the air filter, it's not filtered ( never understood why the OEM would pull air into the crankcase tgatbhad no filter. My 67 dart 273 is the same way
 
Dana67Dart said:
never understood why the OEM would pull air into the crankcase tgatbhad no filter
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what I always suspected was that it was to ensure that crankcase gases would get pulled into the intake when the pcv valve was closed at idle or off throttle. Maybe this isn't right, but it seems to be a pollution control device. My mom's california 1964 ford has that tube, but the 49 state cars don't.
 
remytherat said:
seems to be a pollution control device
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I believe it is more that then anything else.

Earlier engines just had breathers.

To my mind if you pull a vacume to the PVC valve the gasses go into the intake.

The air to keep the crank case from pulling a strong vacume and sucking oil etc down from around the rings comes from the other breather.

The air that goes into that breather IMHO should be filtered so fine dust does not enter the crankcase under vacume that would open the PVC
 
The early breather cap does have an element inside but its nothing more than fiberglass mesh. Small particles can pass through it. With enough heat and age the fiberglass can crumble to become the small whisker like debris/particles in the engine. Todays paper air filters and foam crankcase filters can dry rot, crumble and contaminate an engine too. Another plus for the electric motors?
 
Any way you look at it, it's EPA pollution mandated B.S. & not well thought out to begin with, just like most pollution control stuff on older cars. It ends up being worse than the cure.
 
Dana67Dart said:
I like the filtered breather if you are going non stock.

where the OEM hose attached to the OEM filter housing is actually outside the air filter, it's not filtered ( never understood why the OEM would pull air into the crankcase tgatbhad no filter. My 67 dart 273 is the same way
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Good catch, My Mazda has a fiber filter where that hose is and its discolored so maybe its more of a vent FROM the valve cover to draw in crankcase fumes through the round air cleaner element to burn? There is always a lower pressure within the air cleaner so drawing in gasses makes sense, and there is almost always positive crankcase pressure from blowby. These systems evolved from year to year from a wide open hanging draft tube, to the PCV valve sucking on a cross ventilated rocker cover to todays completely closed filtered systems. If you buy a Mr Gasket Chrome air cleaner you get a knockout inside the filter element footprint.
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I took the stock filtered cap and cleaned it up real purty then added an aftermarket filter. This keeps the blow-by oil to a minimum. The low vacuum blow-back fumes are not too bad. The filter uses a screw clamp, match the o.d. of the cap and slide the filter on.

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Ohio66Cuda said:
I was thinking of changing current air cleaner to something newer (chromed?). What to do with the connection to the air breather on the valve cover?

Do I need that connection?

View attachment 1716123451
Click to expand...

You don’t need that connection, you can use a breather that doesn’t have a hose outlet in its place.

When there is high crankcase pressure the fumes will pour out of the breather onto the valve cover instead of getting sucked up by the air intake, that’s the only difference.
 
Dana67Dart said:
I believe it is more that then anything else.

Earlier engines just had breathers.

To my mind if you pull a vacume to the PVC valve the gasses go into the intake.

The air to keep the crank case from pulling a strong vacume and sucking oil etc down from around the rings comes from the other breather.

The air that goes into that breather IMHO should be filtered so fine dust does not enter the crankcase under vacume that would open the PVC
Click to expand...
From what I can gather from the posts the breather has to be there but the filtering is questionable. I'll have to pull it off and inspect the condition.
 
I have seen fords that had an oiled steel wool like material in the breather
 
Yes, you need that connection because it provides clean filtered air as the inlet for the PCV system. Post #10 shows a nice, neat alternative. Since the PCV system also aids in ring seal, it's "MORE" then just emissions equipment.
 
The PCV system definitely needs a filtered breather, but that hose doesn’t provide filtered air, the filter within the breather itself filters the air. That hose is connected outside of the carburetor air filter.

As far as I can see running a hose from the breather to the air filter directs excess blow-by directly to the air cleaner instead of to the engine compartment.

Without that hose you’ll have some oil on your valve cover, not a big deal.
 
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