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Old 05-19-2023, 11:58 AM   #1
1911a1
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will this PCV work

The Mr Gasket push in breather goes in the opposite valve cover.
My friend has some that are more of a little open cylinder filter push in breather I could substitute.

anyhow thoughts on this set up.



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Old 05-19-2023, 01:23 PM   #2
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Re: will this PCV work

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Old 05-19-2023, 01:33 PM   #3
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Re: will this PCV work

not sure what actual PCV valve you have, but otherwise the plumbing will work.

With that said I have read, due to rotation of engine, the PCV should be PS and breather DS. You could just flip the VC to other sides if you wanted to have it plumed that way if the VC holes are specific to PCV and breather size ports
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Old 05-19-2023, 01:35 PM   #4
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Re: will this PCV work

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not sure what actual PCV valve you have, but otherwise the plumbing will work.

With that said I have read, due to rotation of engine, the PCV should be PS and breather DS. You could just flip the VC to other sides if you wanted to have it plumed that way if the VC holes are specific to PCV and breather size ports
Thanks for the info!
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Old 05-19-2023, 01:35 PM   #5
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Re: will this PCV work

The idea of a PCV system is to prevent (or help control) crankcase vapors.. Fresh air enters through the vented cap on the valve cover opposite the PCV valve. The vapors pass through the valve and into the intake manifold with the incoming fuel/air charge. The vapors are burned along with the fuel. This incoming air must be filtered so as to not introduce dirt and other unwanted debris. I don't know what the other "little open cylinder thing" you're talking about, but the filter you have in your hand will do just fine provided it fits the valve nice and tight.
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Old 05-19-2023, 01:54 PM   #6
ghackett1
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Re: will this PCV work

The setup you propose will work, but the cleaner way to do it is to return the spent gases through the air cleaner and back through the engine if possible. Many aftermarket air cleaners have an attachment that can be attached under the air cleaner base itself, sometimes those are included in the box with the unit or available as an option. The proposed set up will work as stated but will also create a bit of a mess over time if not regularly cleaned as the gasses will release into the engine compartment around the top of the valve cover.
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Old 05-19-2023, 01:55 PM   #7
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Re: will this PCV work

Likely like this rusty.


https://www.amazon.ca/62-1600RD-Vent...44790121&psc=1
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Old 05-19-2023, 01:58 PM   #8
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Re: will this PCV work

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Originally Posted by ghackett1 View Post
The setup you propose will work, but the cleaner way to do it is to return the spent gases through the air cleaner and back through the engine if possible. Many aftermarket air cleaners have an attachment that can be attached under the air cleaner base itself, sometimes those are included in the box with the unit or available as an option. The proposed set up will work as stated but will also create a bit of a mess over time if not regularly cleaned as the gasses will release into the engine compartment around the top of the valve cover.


Here is a pic of what I was suggesting by returning back into the engine.
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Old 05-19-2023, 03:15 PM   #9
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Re: will this PCV work

The correct PCV itself is important so it does not allow too much crankcase pressure to build compromising either engine seals or causing oil consumption.

The way I have my PCV plumbed is the "breather" hose goes into air cleaner base, not the PCV draw hose. IMHO you do not want to have the draw (PCV) hose going into carb unfiltered as that just adds crud inside carb. Plumbing it to base of carb it does not go "through" it but instead directly into intake manifold.

A stand alone "breather" in VC like OP has is perfectly fine vs using the air cleaner base and IMHO what I do on V8. My L6 though I have the breather plumbed to base of air cleaner as otherwise a VC breather for my 6 cyl would be sideways and weep some oil out onto exhaust manifold
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Old 05-20-2023, 06:51 AM   #10
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Re: will this PCV work

The PCV system recirculates expelled air & fuel gases that has escaped past the rings into the crankcase and is unavoidable. The smaller hose is attached to a pcv valve inserted through a grommet on top of a baffled valve cover hole on the drivers side. This smaller hose is then routed from the pcv valve to a pcv port located at the base of the carb. THEN from there a 2nd larger pcv hose is attached using another grommet and some type of fitting into the top of the passenger side valve cover baffled hole and out, this 2nd hose is attached from the valve cover to the base or side of the air cleaner which completes and allows the correct circulation of pcv system. These spent gases should travel through a spark arrestor before exiting into the carb.

You can also install into the valve cover push in filtered breathers as typically seen on modified engines.

Last edited by ghackett1; 05-20-2023 at 07:44 AM.
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Old 05-20-2023, 10:06 AM   #11
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Re: will this PCV work

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Originally Posted by ghackett1 View Post
The PCV system recirculates expelled air & fuel gases that has escaped past the rings into the crankcase and is unavoidable. The smaller hose is attached to a pcv valve inserted through a grommet on top of a baffled valve cover hole on the drivers side. This smaller hose is then routed from the pcv valve to a pcv port located at the base of the carb. THEN from there a 2nd larger pcv hose is attached using another grommet and some type of fitting into the top of the passenger side valve cover baffled hole and out, this 2nd hose is attached from the valve cover to the base or side of the air cleaner which completes and allows the correct circulation of pcv system. These spent gases should travel through a spark arrestor before exiting into the carb.

You can also install into the valve cover push in filtered breathers as typically seen on modified engines.
You don't understand how a PCV system works. The connection from the air cleaner to one valve cover is for filtered air into the crankcase. This air and whatever vapors and blowby gases are drawn through the PCV by the manifold vacuum from the hose running to the base of the carburetor. Crankcase gases are never intended to be drawn through the carb, and in fact this only happens on an engine with excessive blowby.
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Old 05-20-2023, 10:18 AM   #12
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Re: will this PCV work

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Old 05-20-2023, 11:21 AM   #13
ghackett1
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Re: will this PCV work

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You don't understand how a PCV system works. The connection from the air cleaner to one valve cover is for filtered air into the crankcase. This air and whatever vapors and blowby gases are drawn through the PCV by the manifold vacuum from the hose running to the base of the carburetor. Crankcase gases are never intended to be drawn through the carb, and in fact this only happens on an engine with excessive blowby.
Chris I stand corrected and per your post I did some research I think I have a better handle on the function of the system now. Makes sense. Thx
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Old 05-20-2023, 10:05 PM   #14
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Re: will this PCV work

>>Crankcase gases are never intended to be drawn through the carb, and in fact this only happens on an engine with excessive blowby.<<

During WOT (wide open throttle) manifold vacuum is at a minimum and at the same time, blow-by is at its maximum. During this event, pressure above the carb, as to say, between the mouth of the carb and the air cleaner, will be low and the increased pressure in the crankcase, will cause crankcase fumes to travel into the air cleaner and through the carb.

During idle and cruise, the high manifold vacuum pulls the filtered air from the air cleaner, into the crankcase, out of the crankcase, through the PCV Valve, then into the intake manifold.
Not all carbs have a vacuum port for the PVC System. Sometimes a vacuum port in the intake manifold is provided for the PCV System.

When you have a valve cover breather, you have what is called an OPEN PCV System. During WOT, crankcase fumes are expelled out into the atmosphere.
A CLOSED PCV System is fully contained and does not expel crankcase pollutants out into the atmosphere.
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Old 05-20-2023, 10:21 PM   #15
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Re: will this PCV work

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Got one on my DD! Excellent piece!
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Old 05-21-2023, 06:42 AM   #16
ghackett1
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Re: will this PCV work

Quote:
Originally Posted by RichardJ View Post
>>Crankcase gases are never intended to be drawn through the carb, and in fact this only happens on an engine with excessive blowby.<<

During WOT (wide open throttle) manifold vacuum is at a minimum and at the same time, blow-by is at its maximum. During this event, pressure above the carb, as to say, between the mouth of the carb and the air cleaner, will be low and the increased pressure in the crankcase, will cause crankcase fumes to travel into the air cleaner and through the carb.

During idle and cruise, the high manifold vacuum pulls the filtered air from the air cleaner, into the crankcase, out of the crankcase, through the PCV Valve, then into the intake manifold.
Not all carbs have a vacuum port for the PVC System. Sometimes a vacuum port in the intake manifold is provided for the PCV System.

When you have a valve cover breather, you have what is called an OPEN PCV System. During WOT, crankcase fumes are expelled out into the atmosphere.
A CLOSED PCV System is fully contained and does not expel crankcase pollutants out into the atmosphere.
I found this to be helpful, it seems to be what is being described in a closed PCV system.
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