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440x6 air cleaner and PCV

Jeff Erwin

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I finally put a PCV valve on my 440 6-pack and noticed something odd. I have the air cleaner where the orange top seals around the oval filter but leaves a gap so you can actually see the air cleaner. I noticed that the port from the passenger-side valve cover to the air cleaner that is pulling air for the venting of the engine is outside the air cleaner. I always thought it was supposed to be drawing air from the inside of the air cleaner. I know it's pulling a lot of air as I can see a faint smoky mist coming from the middle of the filter into the opening at the bottom of the air cleaner base.

The arrow in the pic is pointing to the opening on the outside of the filter that is leading to the intake port for the crankcase ventilation.

Is all this normal? It's been a long time since I've fussed with PCV stuff. Does it matter if the air being drawn in is just fresh air or should it be air from the inside of the filter?

IMG_5836.JPG
 
I think that that connection is to drain the water from the air cleaner base. It should only have a hose that’s about 4-6” long.
 
Your hose connection is correct. There is no water drain in the base.
 
Your hose connection is correct. There is no water drain in the base.

this ^^^^
and the vent hose connection works on the principal of vacuum somewhat by the air passing through the filter going across the hose connection opening. This comes off the breather on the valve cover. the PCV off the other valve cover and connects to the center carb
 
The hose pipe on the air cleaner goes to the valve cover breather NOT the pcv valve


Pcv valve connects to a port on the base of the center carb...pass side
 
The hose pipe on the air cleaner goes to the valve cover breather NOT the pcv valve


Pcv valve connects to a port on the base of the center carb...pass side

I got all of this. The opening at the base of the air cleaner connects by hose to the port at the top of the valve cover on the passenger side. On the other side the port at the top of the valve cover connects to the manifold vacuum source at the base of the center carb. The vacuum draws from the driver side valve cover through the PCV valve which pulls air from the engine, Said air comes from the passenger side from the hole at the base of the air cleaner. Got it, all correct.

My question was whether it's 'normal' for the air to be drawn from the outside of the air cleaner as my setup has it or should that air source be inside the air cleaner.
 
It is normal on the non fresh air six pack cleaners.
Shaker cars also run the breather hose to the back of the air cleaner base. I also have a 71 road runner with air grabber and the breather is routed to the same port on the base.
 
I got all of this. The opening at the base of the air cleaner connects by hose to the port at the top of the valve cover on the passenger side. On the other side the port at the top of the valve cover connects to the manifold vacuum source at the base of the center carb. The vacuum draws from the driver side valve cover through the PCV valve which pulls air from the engine, Said air comes from the passenger side from the hole at the base of the air cleaner. Got it, all correct.

My question was whether it's 'normal' for the air to be drawn from the outside of the air cleaner as my setup has it or should that air source be inside the air cleaner.


Yes
 
It's normal even on a double snorkel cleaner, they all draw from outside the filter.... if they were hooked up inside between filter and carb throat you'd be in a low pressure area and both the breather and PCV would try to suck air out of the engine.
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I think it is outside the air cleaner to guard against a carb backfire as the filter will diffuse the flame, the pcv has a check valve for the same purpose.
 
Your air inlet is the correct position - BUT.
The PCV inlet air is filtered - stock the air inlet breather cap is packed with a thick felt type material.
If your cap is open you will get a lot of crap drawn in to the engine and the oil will get dirty.
I add a little pod filter to the end of the inlet tube. They are about $15 I think they are made by Sumitomo or something like that. The rice burner guys use them.
 
I will check the breather cap, good advice.

440 6-pack <> rice burner
lol check your math
 
I agree with #11's assessment. The hose connects from the valve cover breather to the nipple on the air filter base with a short length of hose. At zero manifold vacuum, the crank case fumes will be directed to the air cleaner base and presumably (hopefully) will be injested thru the filter, preventing these evil gremlins from being discharged to the atmosphere.....
 
preventing these evil gremlins from being discharged to the atmosphere.....
Yep and burned and out the exhaust pipe instead! Like GM's air pump blowing into the exhaust manifolds, "watering down" the PPM of the exhaust... :realcrazy:
 
Yep and burned and out the exhaust pipe instead! Like GM's air pump blowing into the exhaust manifolds, "watering down" the PPM of the exhaust... :realcrazy:

I agree.....personally, the entire idea of injecting air into the exhaust gas, was not as GM advertised, BUT a ruse. GM called it the Auto-Thermac. It was claimed to "burn" the hydrocarbons but I believe, merely diluted the HC and CO to a tolerable value, since the bulk of the injected air was nitrogen, which is basically inert, and does nothing. Just my opinion of course....
BOB RENTON
 
Actually Ford and Mopar also used air pumps on some years to help clean up emission's. But on the closed PCV system like the pic posted on #11 the reason they did that was so at wide open throttle when vacuum is about zero instead of crankcase fumes pushing out the valve cover with the open breather the fumes will go back into the air cleaner and still get pulled into the eng and burnt when vacuum is to low to pull the fumes through the PCV valve. Just part of the emission updates over the years and as was said most of the breathers all have a filter type system in them to filter the air the pcv system is pulling into the eng. And as said yours looks right. Ron
 
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