The "Catch Can" Explained!

[RJT-SS]

Thanks!

[rdblan2]

Uhhhh...I bought the dual valve for my whipple after exchanging a few messages with you. Please tell me that's not the wrong one.

[SC2150]

Nope. The dual valve is great, not needed for average driver, but if you drive aggressively use the dual/ Just adds redundancy as far as evac source.

[rdblan2]

Originally Posted by SC2150

Nope. The dual valve is great, not needed for average driver, but if you drive aggressively use the dual/ Just adds redundancy as far as evac source.

Excellent!

[SC2150]

http://www.aa1car.com/library/what_i..._injection.htm

Read for explanation of DI engines and an accurate diagram showing its operation to undersatnd why this has become such an issue.

[Cheetoh]

I purchased a Duel Valve Catch can, but decided to just go with the single valve and block off the other fitting. Do i still use the hose with the checkvalve in it, or go for one without a check valve?

[air1kdf]

Originally Posted by Cheetoh

I purchased a Duel Valve Catch can, but decided to just go with the single valve and block off the other fitting. Do i still use the hose with the checkvalve in it, or go for one without a check valve?

Use the side with the valve

[SC2150]

Yes. Just make sure flow goes away from the can outlet to the IM. center is always the inlet.

[cbass]

Originally Posted by Oldag

Have to disagree here. Breather caps were all that was available until around 1970 or so (give or take a few years). PCV systems have not been on cars since day one. The statement of substantially accelerated wear is not substantiated.

Letting the fumes go to atmosphere will not accelerate wear as opposed to leaving the PCV system in place. And as has been pointed out, not recycling those fumes into the intake has advantages.

The average car will not see a benefit between pulling a mild vacuum and venting to atmosphere.

Will disconnecting the PCV cause error codes? I do not know. This could be a complication.

I still don't understand how it would lead to more rapid wear either. I think what you are saying is because there is no vacuum there is no way to pull out the combustion bi-products and they remain in the crankcase which leads to wear.

Is the correct? If so, then wouldn't an oil analysis identify unburnt fuel and water?

Also, if carbon particles accumulate, then wouldn't a vacuum to scavenge them trade bottom end wear for top end wear?

[SC2150]

Yes. There must be constant evacuation taking place while the damaging combustion byproducts are still in a suspended or gaseous state.

Oil analysis is an excellent way to see whats happening.

[cbass]

Originally Posted by SC2150

Yes. There must be constant evacuation taking place while the damaging combustion byproducts are still in a suspended or gaseous state.

Oil analysis is an excellent way to see whats happening.

So the first part I understand. If evacuation doesn't happen, then the crankcase will develop corrosive deposits.

However, I have seen engines that vent to atmosphere that have shown zero problems on an oil analysis report when it comes to water %, fuel %, and Insoluables %

If what you say it true, the shouldn't that show up on the oil analysis? If so, why doesn't it show up on the oil analysis? Is it dependent on engine design?

The other thing is putting those gasses back into the intake has it's own disadvantages. The catch can may solve the problem of separating the oil out, but the gasses going back in are taking the place of fresh air.

[SC2150]

Now let me clarify this is not attacking you as only you and the other party your talking to know the truth. And, this is such an inexpensive mod to do correctly, why would anyone want to take the chance and not protect their investment the best way possible?

I would argue with all the years of doing oil analysis that your mistaken on this, and there is white paper after white paper on this from engineers and engine builders doing the oil analysis's as well (I would go out on a limb and suspect someone is feeding you this inaccurate info and you are just repeating what they are telling you so not attacking you, your source is BS'ing).

I have been building race and performance engines for over 38 years, doing super charging and turbo charging of all types since the mid 1970's, and have owned, raced, managed, sponsored professional drag teams for ages in both NHRA & IHRA in multiple classes, with years of Divisional, National, and World Championships through this time as well and oil analysis, proper crankcase evacuation, and durability keep us in the winners circle so I am not just pushing a product or arguing for arguments sake, this is actual experaince....and most likely, whoever is feeding you this inaccurate info was not even born yet when we were racing and building engines...and is a competitor not playing fair.

Read (long) from the aircraft engeering side (where the pilot/passengers life is dependant upon proper crankcase evac to keep engine sound:
http://www.skydynamics.com/Informati...11_Pg12-19.pdf

Another engineers standpoint: (many of these deal with off road use)

http://forum.diyefi.org/viewtopic.php?f=24&t=357

http://www.enginebasics.com/Engine%2...ntilation.html

Very technical Patent data and reference material:
http://www.google.com/patents/EP1169554B1?cl=en

A basic on what is seen in oil analysis:
http://www.kleenoilusa.com/index.php...alysis-reports

But where do these damaging compounds come from?

A clogged or defective PCV valve can contribute to sludge formation. If this valve does not operate properly, harmful exhaust gases remain in the crankcase.
These gases, which contain water, acids, soot, etc., promote sludge. Excessive amount of fuel due to leaky fuel injectors, malfunctioning choke mechanism or failed oxygen sensor can also contribute to sludge formation.

Maintain your vehicle in good operating condition. Check fluid levels, filters, belts and hoses periodically.
Make sure your car is well tuned.
Most light duty vehicles sold in USA after 1996 when OBD-II regulations went into effect, no longer require any "normal" tune-ups.
However when you check engine (MIL) light comes on and stays on, have your vehicle checked by a professional mechanic with proper computer diagnostic tool.
(That is the computer gizmo that connects to the OBD-II port in your vehicle).
The MIL (Malfunction Indicator Light) also known as "Engine Check Light" does not necessarily indicate any engine problems, it is designed only to indicate any failure that results in excessive tailpipe and/or evaporative emissions from your vehicle, however and efficient combustion produces far fewer harmful acids, soot, unburned fuel than a poorly or rough running engine.

I can go on and on, but the point is, yes, plenty run with inadequate carnkcase evacuation and "see" no obvious over night damage" so the assumption is generally
"all is fine".

I am sharing a lifetime of experiance and first hand knowledge. I invite you if ever in the area to stop in a tour the facility and see all this forst hand up close and personal to see it first hand. No bull, no political games, no assumptions.

[cbass]

Now let me clarify this is not attacking you as only you and the other party your talking to know the truth. And, this is such an inexpensive mod to do correctly, why would anyone want to take the chance and not protect their investment the best way possible?

I would argue with all the years of doing oil analysis that your mistaken on this, and there is white paper after white paper on this from engineers and engine builders doing the oil analysis's as well (I would go out on a limb and suspect someone is feeding you this inaccurate info and you are just repeating what they are telling you so not attacking you, your source is BS'ing).

No offense taken. I am just looking to have a discussion about this. You have invested a lot of time into this and you are sharing your technical knowledge and with me being curious by nature I am taking the opportunity to pick your brain and try to understand.

The person BS'ing me is well me. These are my own oil analysis results although on a different engine than a V8.

Like I have said before I am curious by nature and like to tinker with engines. However, I am someone that needs measurable results to prove something is correct or not.

For example, K&N oiled filters compared to paper filters. There have been several experiments and large debates that more flow = less filtration = more dirty air = more wear. There have been many articles and results published that K&N filters do not filter as well as paper and therefore can lead to more rapid wear on the engine.

Since I run a K&N filter I obviously was concerned. I figured if their theory was correct, then on the oil analysis poor filtration would show up as silicon content. I have done oil analysis several times and never has silicon been high with a K&N filter so I continue to use it. My reasoning is if it was true, then why wouldn't it show up in a UOA report?

The same is true for an open breather. I understand the importance of purging the cases and I have seen the results of poor breathing and the sludge and water that has built up in the cases.

At the same time I run an open breather into essentially what you call a beer can catch can. Since the catch can is not effective like a RX can I chose not to connect it back into the intake and ingest oil. However, again I have never seen anything show up on the oil analysis that would indicate this is a problem. Maybe because my setup has a draft tube at the bottom of the can and is in the slip stream?

My only question was if my approach was not working, then shouldn't it show up in UOA? I don't run a RX catch can in that application because you don't make one

[Apex Motorsports]

Originally Posted by cbass

I don't run a RX catch can in that application because you don't make one

I bet Tracy can fix that.