[Elite Engineering]

With all the talk about Catch Cans, we thought it would be a good idea to combine the information into a smaller thread here. We'll continue to edit and add additional information and answer any questions we can.


To better understand the purpose of a good quality PCV Oil Catch Can and why they are important, we need to first understand the purpose of your Stock PCV System:

The PCV (Positive Crankcase Ventilation) system on your engine is designed to regulate and remove fumes from the engine crankcase, and to alleviate crankcase pressure which could cause oil leaks or seal damage. It’s a way for gases to escape in a controlled manner from the crankcase of an internal combustion engine.

During normal operation of an internal combustion engine, there’s a compressed air and fuel mixture inside the combustion chamber that is ignited and as a result, forces the piston down. A small amount of that ignited mixture leaks past the piston rings and ends up in the crankcase.

This leakage is often referred to as “blow-by” (leakage past the piston rings), as well as oil mist. Some of the oil mist and other products settle along the engine intake and over time form a “gunk.” The oil catch can collects the oil mist and condenses the fuel vapors while allowing “cleaner” gases to be passed back into the intake.

If these contaminates are kept inside the combustion chamber, they will eventually make their way into the oil inside the crankcase and cause oil contamination and dilution or make their way back into the intake manifold.

This problem has been documented in many automotive magazines, Car & Driver had an article covering this topic (Carbon Deposits with Direct Injection) There are hundreds of images on the Internet of Carbon Build up on Intake Valves:

http://www.gm-trucks...-can/?p=1608015



The purpose of a proper oil separating Catch Can is to route these gasses through a baffle system that provides the most contact possible with the outer surface resulting in the oil being trapped and removed from the other gasses that do continue on through the intake and are burnt and consumed. Typically the trapped oil is captured in the bottom of the Catch Can.





If you do your homework, you’ll find a lot of good Catch Cans on the market. You will also find a lot of products that claim to be Catch Cans but have no internal design or baffling to create the optimum amount of pressure drop to pull the oil out of the vapor.
Many Catch Cans on the market are just comprised of an empty container with 2 ports. While that simple design may trap a few oil droplets, a well-engineered Catch Can is designed to condense the oil vapor and trap the oil inside the container.
As I said, there are a lot on the market, go with a company you can trust.
Attached Thumbnails

• 
• 

[MIAMI2SSRS]

Thank you for sharing the knowledge and info. Maybe a stupid question and my apologies if it is. It seems this would be a good thing to install in the cars and I would like to have one but is there any chance this would affect the warranty in any way shape or form?

Thanks.

[Richard0nee]

Originally Posted by MIAMI2SSRS

Thank you for sharing the knowledge and info. Maybe a stupid question and my apologies if it is. It seems this would be a good thing to install in the cars and I would like to have one but is there any chance this would affect the warranty in any way shape or form?

Thanks.

Wondering the same thing. I know for turbo cars it's critical and it can be the same for direct injection vehicles.

Spoke to the dealer regarding the catch can and his replay was... "What's a catch can?"

[MIAMI2SSRS]

Originally Posted by Richard0nee

Wondering the same thing. I know for turbo cars it's critical and it can be the same for direct injection vehicles.

Spoke to the dealer regarding the catch can and his replay was... "What's a catch can?"

That is funny. Sad but funny.

[bigdonut]

Alright, why don't engineers add them? If they want to "prolong" the life of their engine, seems like they would engineer and install a catch can—an easily sub-100 dollar upgrade. Do companies like Mercedes Benz use catch cans on their V12 biturbo engines? By all means, they have the capital to do so.

[BAMF]

This was very well written. Thank you for posting this. I too am now very interested in getting one, after doing a bit more research.

[dragonZ28]

Originally Posted by bigdonut

Alright, why don't engineers add them? If they want to "prolong" the life of their engine, seems like they would engineer and install a catch can—an easily sub-100 dollar upgrade. Do companies like Mercedes Benz use catch cans on their V12 biturbo engines? By all means, they have the capital to do so.

No manufacturer wants to place a maintenance device in the hands of the user. This would dissuade some purchasers that simply were perplexed. But, make no mistake. A catch can is an absolute must for a direct injection engine. I recommend it 100%. There are no tricks to the product to give you false results. The oil/fuel/gunk they catch would otherwise go into the intake tract and foul your heads and intake valves.

[BAMF]

Originally Posted by dragonZ28

No manufacturer wants to place a maintenance device in the hands of the user. This would dissuade some purchasers that simply were perplexed. But, make no mistake. A catch can is an absolute must for a direct injection engine. I recommend it 100%. There are no tricks to the product to give you false results. The oil/fuel/gunk they catch would otherwise go into the intake tract and foul your heads and intake valves.

Does it void the warranty? If so, what is the reasoning for that?

[thescreensavers]

If you look at other cars that are DI such as the early Audi/VW engines we keep seeing pictures of a catch can did not solve the issues at all. Some oils do a bit better then others, looking at low NOACK% ..etc. Also Horrible carbon issues have not been proven to be an issue on the new LT1 engine and GM already installed a "catch can" on the Camaros LT1 which automatically drains into the oil sump.

TLDR: you will add another item to worry about to drain..etc and the valves will probably still get gummed up if its an issue.

You can also reduce deposits by doing an "Italian Tune up" these pictures shown are most likely from consumers who "never get above 3k"

[bigdonut]

Originally Posted by dragonZ28

No manufacturer wants to place a maintenance device in the hands of the user. This would dissuade some purchasers that simply were perplexed. But, make no mistake. A catch can is an absolute must for a direct injection engine. I recommend it 100%. There are no tricks to the product to give you false results. The oil/fuel/gunk they catch would otherwise go into the intake tract and foul your heads and intake valves.

One could argue that an air filter is a maintenance device, or even an oil filter. Manufacturers are comfortable giving us oil filters, so why wouldn't they give us a catch can?

How can we quantify the benefits of a catch can?

[pete1077]

Originally Posted by dragonZ28

No manufacturer wants to place a maintenance device in the hands of the user. This would dissuade some purchasers that simply were perplexed. But, make no mistake. A catch can is an absolute must for a direct injection engine. I recommend it 100%. There are no tricks to the product to give you false results. The oil/fuel/gunk they catch would otherwise go into the intake tract and foul your heads and intake valves.

Exactly! Some people have trouble remembering to change their oil. Imagine the general public (non car enthusiasts) needing to remember to periodically empty a catch can?

I also think another reason manufacturers don't install OEM catch cans is the carbon deposits build up very slowly and there is a good chance, there wouldn't be any noticeable issues until long after the power train warranty expires.

[Elite Engineering]

Originally Posted by MIAMI2SSRS

is there any chance this would affect the warranty in any way shape or form?

Thanks.

The short answer is, absolutely not.

Now are there some dealers out there that will try to point to the installation of a Catch Can as a means to deny a warranty? Probably so, but legally it will not void your warranty.

Here's some good information from another source:

Despite all the bad information out there, it is pretty cut and dry because there is federal law on the matter. The Magnuson-Moss Warranty Act (15 U.S.C. 2302(C)) regulates warranties and protects the consumer. This legislation was enacted in 1975 in response to widespread deceptive warranty practices in many industries. Here is how SEMA summarizes things:

The essence of the law concerning aftermarket auto parts is that a vehicle manufacturer may not condition a written or implied warranty on the consumers using parts or services which are identified by brand, trade, or corporate name (such as the vehicle maker's brand) unless the parts or service are provided free of charge. The law means that the use of an aftermarket part alone is not cause for denying the warranty. However, the law's protection does not extend to aftermarket parts in situations where such parts actually caused the damage being claimed under the warranty. Further, consumers are advised to be aware of any specific terms or conditions stated in the warranty which may result in its being voided. The law states in relevant part: No warrantor of a consumer product may condition his written or implied warranty of such product on the consumers using, in connection with such product, any article or service (other than article or service provided without charge under the terms of the warranty) which is identified by brand, trade or corporate name... (15 U.S.C. 2302(C)).

So in short, this means a service department or automotive manufacturer can not void your warranty simply because you have installed aftermarket parts or have modified your vehicle. They can, however, deny a warranty claim if they can prove the issue in question was a direct result of the installed part or modification. Unfortunately, plenty of people have stories of going to a dealership service department with a warranty issue and being denied because they have modified their vehicle. There are definitely shady service departments out there who will try to get over on their customers if they can, but this is illegal and it is up to the customer to know the law and stand up.


Here is an example of what can not be denied:

You install a supercharger in your vehicle and a month later your drivers side window stops working. The supercharger has no impact on your electric window motor, therefore, the repair should be covered.


Here is and example of what could be denied:

You install a supercharger in your vehicle and a month later your clutch is toast. The additional power created by a supercharger can easily overpower a stock clutch and lead to the repair not being covered under warranty.

[MIAMI2SSRS]

Thank you for the follow up. I appreciate it.

[6spdhyperblue]

Originally Posted by Elite Engineering

This problem has been documented in many automotive magazines, Car & Driver had an article covering this topic (Carbon Deposits with Direct Injection) There are hundreds of images on the Internet of Carbon Build up on Intake Valves:

http://www.gm-trucks...-can/?p=1608015

is this a picture of a genv GM engine? im thinking not

hundreds of images and not one of a gen v engine? these engines have been on the road since Q2 2013...