PCV Oil Catch Can, see what your engine is burning!

[drdd]

the manufacturer's packaging states that the Average Air Flow (based on 100 psi inlet pressure with 5 psi drop) is 24.8 SCFM. It is a 5 Micron filter (meaning it's designed to filter particles of 5 microns or bigger) and the body material is zinc.

I do not know what the SCFM is for our PVC systems. how can it be measured?

can psi be converted to SCFM or ACFM ?

Originally Posted by JoulesWinfield

If anyone is actually interested in finding out the possible impact of the filter being clogged.
We need to find out the actual SCFM for the PCV.
If anyone knows that we can get the SCFM for the coelesing filter and determine a percentage of plugging that is acceptable.

The fact is that when you are using a filter of any kind particles of debris are trapped in the filter, especially when you are using an oiled filter.
Not just to disagree with LT but I would like to know what the flow is through the PCV before I put anything in front of it.

[drdd]

I completely understand you hesitations, however, since the filter is a dense, zinc (most likely embedded in carbon) filter (similar to your Brita water filter), it will more likely reduce performance in filtering ability, rather than clog. In other words, that nasty oil vapor schtuff will flow through faster, rather than slower (clog). Also, the o-ring seal will probably loose its efficiency before the filter fails.

thoughts?

Originally Posted by Brian R.

I was not referring to the oil in the trap, I was referring to the filter, obviously. I don't buy the assumption that it will never clog.

[Brian R.]

5-micron filter? Reminds me of the old bronze or metallic filters we used to use in the carburetor's gas inlet (Quadrajet? Holley?).

I wish I had one in my hands - However, all I know is that filters clog. It is only a matter of how fast. This is a filter that is being used for a purpose that it was not designed for in a system that was not designed for a filter - Also the system that if flow is restricted, crankcase (oil) contamination increases.

I am much too cautious to do this type of mod without having some way to test if the filter is clogging. Maybe replacing the entire unit (if that's what it takes) every 10k or so for peace of mind. Maybe back-flushing the filter with solvent periodically would be enough. I know that the old gasoline filters I mentioned above could not be cleaned by back-flushing. You had to throw them out once you got fuel starvation.

Maybe nothing is ever needed to keep it free-flowing. You guys will find out.

[drdd]

yeah, I agree with most of what you're saying ...

the proof may lie in the PCV SCFM rating ...

I would disagree on the point that the filter is being used for a purpose that it was not designed for ...

the manufacturer's description says that it is "... a general purpose filter [that] is designed to remove most liquid and solid particles from the air supply."

it seems to be doing that satisfactorily ...


at the risk of sounding too "unscientific" ... do not all filters clog or otherwise lose their effeciency? of course they do. Is an engine DESIGNED to run on a perfectly clean, brand-new air filter? what if that air-filter is slowly clogging? after 50 miles? after 100 miles?

what about oil? is a system DESIGNED to run on a brand-new filter? should we be sceptical of that system after 50 miles? after 100 miles?

hmmm ... our air intakes were not DESIGNED with a CAI, "cone-type", 360 degree filter in mind ...

more ideas!! keep 'em coming!!

anyone on SCFM ???????????????????????

would the SCFM of (a particular make/year) a PCV system be the "proof" ???

Originally Posted by Brian R.

5-micron filter? Reminds me of the old bronze or metallic filters we used to use in the carburetor's gas inlet (Quadrajet? Holley?).

I wish I had one in my hands - However, all I know is that filters clog. It is only a matter of how fast. This is a filter that is being used for a purpose that it was not designed for in a system that was not designed for a filter - Also the system that if flow is restricted, crankcase (oil) contamination increases.

I am much too cautious to do this type of mod without having some way to test if the filter is clogging. Maybe replacing the entire unit (if that's what it takes) every 10k or so for peace of mind. Maybe back-flushing the filter with solvent periodically would be enough. I know that the old gasoline filters I mentioned above could not be cleaned by back-flushing. You had to throw them out once you got fuel starvation.

Maybe nothing is ever needed to keep it free-flowing. You guys will find out.

[Brian R.]

Originally Posted by drdd

I would disagree on the point that the filter is being used for a purpose that it was not designed for ...

the manufacturer's description says that it is "... a general purpose filter [that] is designed to remove most liquid and solid particles from the air supply."

it seems to be doing that satisfactorily ...

I would identify a general purpose filter as one not specifically designed for any particular application (purpose is the wrong word). It obviously functions in a high-pressure system ok (compressed air), but I was specifically referring to its use as a filter in the PCV system.

Originally Posted by drdd

at the risk of sounding too "unscientific" ... do not all filters clog or otherwise lose their effeciency? of course they do. Is an engine DESIGNED to run on a perfectly clean, brand-new air filter? what if that air-filter is slowly clogging? after 50 miles? after 100 miles?

what about oil? is a system DESIGNED to run on a brand-new filter? should we be sceptical of that system after 50 miles? after 100 miles?

I believe they design engines to run on many restrictions of air and oil filters so that there is no significant problem with using them within recommended change intervals (and beyond). Neither of them is a good analogy to this filter.

Originally Posted by drdd

hmmm ... our air intakes were not DESIGNED with a CAI, "cone-type", 360 degree filter in mind ...

more ideas!! keep 'em coming!!

anyone on SCFM ???????????????????????

would the SCFM of (a particular make/year) a PCV system be the "proof" ???

Let's not get too carried away here...

[ZL1power69]

Originally Posted by Brian R.

I was not referring to the oil in the trap, I was referring to the filter, obviously. I don't buy the assumption that it will never clog.

i check both the oil level and the filter. I have not had a problem yet with the filter cloging.

[JoulesWinfield]

I was just thinkin that a 5 micron filter designed for 100psi pressure used in a system that is generating probably like 12inHg might be some cause for concern. Like Brian said this system was not designed to utilize a filter.

While BlazerLT has a great mod here, and I applaud his efforts and innovation, I am a little concerned about the flow restriction in a vacuum system.
What is going to happen if that vacuum level is doubled and flow is cut in half?

See, when dealing with vacuum vs compressed air you have totally different variables.

Typically when you restrict air flow in a pressurized system all you get is less flow. When you restrict flow in a vacuum system you could get increased levels of vacuum as well as reduced flow. Dependant on where the restriction is in the system. So the real question is what is going to happen as a result? Otherwise what do "I" need to do to avoid any restriction? Then I dont need to be concerned with the side effects.

I intend on trying this out once I can convince myself that I can do it without any potential damage.

[herkyhawki]

Originally Posted by drdd

the manufacturer's packaging states that the Average Air Flow (based on 100 psi inlet pressure with 5 psi drop) is 24.8 SCFM. It is a 5 Micron filter (meaning it's designed to filter particles of 5 microns or bigger) and the body material is zinc.

I do not know what the SCFM is for our PVC systems. how can it be measured?

can psi be converted to SCFM or ACFM ?

PSI is a measure of pressure. ACFM and SCFM are measurements of flow. There is no"conversion" factor to equate pressure to flow.
The PCV flow rate of a seasoned 4.3L is in the range of 8-10 ACFM (approx 6-8 SCFM).

24.8 SCFM( at 100 psi) = 3.2 ACFM. If this filter really has 5 psi pressure drop at 3.2 ACFM then it is too restrictive for use as described in this thread.
Those who leave this filter installed can do a reality check by monitoring the oil deposits in the PCV inlet breather line (fresh air inlet hose from air filter to valve cover) and deposits on the throttle butterfly. As flow is restricted in the PCV valve line, blowby will be forced to flow out the inlet and will then be mixed with intake air.
Use a Q-TIP to swab the inside of the inlet breather line. Oily residue would only be there if you are flowing backwards.

[BlazerLT]

Originally Posted by Brian R.

5-micron filter? Reminds me of the old bronze or metallic filters we used to use in the carburetor's gas inlet (Quadrajet? Holley?).

I wish I had one in my hands - However, all I know is that filters clog. It is only a matter of how fast. This is a filter that is being used for a purpose that it was not designed for in a system that was not designed for a filter - Also the system that if flow is restricted, crankcase (oil) contamination increases.

I am much too cautious to do this type of mod without having some way to test if the filter is clogging. Maybe replacing the entire unit (if that's what it takes) every 10k or so for peace of mind. Maybe back-flushing the filter with solvent periodically would be enough. I know that the old gasoline filters I mentioned above could not be cleaned by back-flushing. You had to throw them out once you got fuel starvation.

Maybe nothing is ever needed to keep it free-flowing. You guys will find out.

Brian,

The filter will not clog. There is no way this rigid filter type material will clog with a liquid.

The filter is not like you standard filter and you should go and actually look at these filters before you state they will clog. I have mine here and I KNOW it won't clog.

We aren't dealing with solids here, only GAS, and LIQUIDS.

[Brian R.]

Originally Posted by BlazerLT

Brian,

The filter will not clog. There is no way this rigid filter type material will clog with a liquid.

The filter is not like you standard filter and you should go and actually look at these filters before you state they will clog. I have mine here and I KNOW it won't clog.

We aren't dealing with solids here, only GAS, and LIQUIDS.

If there are no solids in your crankcase, why use an oil filter? The crank puts liquid oil from the sump into the air above the crankcase as a mist containing everything that is in the crankcase, including oil and the solids that you need an oil filter for. This mist is part of what you are sucking up in the PCV system. That is where the solids I am talking about are coming from. There may not be much, but you will never get me to believe they don't exist.

@ZL1power69: I don't expect you will have trouble with the filter element after a week or two of use. I'm talking about years and 10s of thousands of miles from now.

Really - You guys may have a fool-proof system for trapping PCV emissions. I am not going to argue about it further because it's only a possibility I'm raising and I have nothing to back up my concerns except what I envision under worse-case usage. I don't think there is anything further that I can add to this discussion.

True experts are constantly being surprised when they see that something totally unexpected happened in a system they have studied for years and thought they knew everything there is to know about that system. You are only fooling yourselves if you think you "know" something, even in a simple system. I am humble enough to know that I don't "know" everything about much of anything of complexity.

Keep an eye on that trap and Good Luck. It's probably bullet-proof as LT says.

[BlazerLT]

Originally Posted by Brian R.

If there are no solids in your crankcase, why use an oil filter? The crank puts liquid oil from the sump into the air above the crankcase as a mist containing everything that is in the crankcase, including oil and the solids that you need an oil filter for. This mist is part of what you are sucking up in the PCV system. That is where the solids I am talking about are coming from. There may not be much, but you will never get me to believe they don't exist.

Comon Brian, comparing this system to your oil filter system is not warranted and is unfounded. Solids don't flow up out of the valve cover.

You are really turning this thread negative.

The PCV system recycles gases and fuel and oil vapor, not solids.

If you had solid flying around you valve cover and in your intake wouldn't your whole intake be full of sand after 100,000 miles?

Cleaning the filter every oil change probably wouldn't hurt but really this arguement has gone to far.

Let's drop it and move onto discussing everyone's experience with the mod instead of constantly negatively talking about all the "possible" worse case scenarios.

Hell, even changing your air filter can be just as damaging as this mod.

[herkyhawki]

Originally Posted by BlazerLT

Solids don't flow up out of the valve cover.
The PCV system recycles gases and fuel and oil vapor, not solids.
If you had solid flying around you valve cover and in your intake wouldn't your whole intake be full of sand after 100,000 miles?

The gas flowing within your crankcase and flowing out through PCV does contain solids. Proof of this is the grimy deposits that form inside the engine, inside the valve covers and inside the intake plenum. These deposits contain millions of solid particles.
If your engine did not have these solids deposited throughout, then what were you getting rid of with your AutoRX snake oil??

[TonyMazz]

Originally Posted by herkyhawki

The gas flowing within your crankcase and flowing out through PCV does contain solids. Proof of this is the grimy deposits that form inside the engine, inside the valve covers and inside the intake plenum. These deposits contain millions of solid particles.
If your engine did not have these solids deposited throughout, then what were you getting rid of with your AutoRX snake oil??

[Brian R.]

Originally Posted by BlazerLT

Comon Brian, comparing this system to your oil filter system is not warranted and is unfounded. Solids don't flow up out of the valve cover.

It is a valid comparison. Both are exposed to the crankcase contents. They are both involved in getting rid of unwanted contaminants in the oil. Both are filters.

There are solids in the crankcase mist - and I'm not talking about sand. Don't be ridiculous.

I am trying, apparently in vain, to drop this subject by agreeing to disagree - let it alone. Let people make their own decisions. I am willing to drop this, but do not think you will get me to agree with you or to allow you to make such illogical statements without challenge, such as using issues like sand in the valve covers and changing air filters. Exagerations and poor analogies will get you nowhere. It is only an insult to me to see you make such statements, obviously without thinking about what I am saying.

[BlazerLT]

Originally Posted by herkyhawki

The gas flowing within your crankcase and flowing out through PCV does contain solids. Proof of this is the grimy deposits that form inside the engine, inside the valve covers and inside the intake plenum. These deposits contain millions of solid particles.
If your engine did not have these solids deposited throughout, then what were you getting rid of with your AutoRX snake oil??

Just looked at my filter will over 1000 miles on it.

Nope, none of these supposed solid plugging it up.

Why are people hypothetically arguing their point when they don't even have it installed or oven looked at the filter. Ask all the guys that have installed it and see if this filter is clogging up with this phantom solids that everyone is bringing up, yet doesn't seem to be in the filter I have?

And thanks for the Snake oil remark cheapshot.