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This is a catch can from a Base C7 with only 300 miles since installed. Please understand that this oil would've ended up on the valves if it wasn't caught in this Catch can causing caking on the valves. Direct injection is really great, but gas won't wash the valves off when oil from the PVC allows oil to enter the intake.
This has been talked about before, but I think it is important to address this situation again. Yes, the catch can is very necessary.
Capt Bob

 

WOuld the installation of a catch can affect the warranty in any way?

 

Only if it screws something up.....I mounted one and was getting about 1/4 tsp per month the way I drive, took it off and sold it. Don't need the clutter and don't believe that chev "forgot it" based on an article written by a GM'ER to mike @ Criswell:

I was the one that contacted someone from the Stingray Consultant team from GM...Here is what he wrote back on this matter.

"The Stingray was evaluated with over one million development miles on 200 captured test fleet cars. There are tens of thousands of direct injection vehicles on the road from General Motors alone. During the evaluation hundreds of engines were literally torn down in to part piles and evaluated. There are hundreds of thousands of LSx family of motors (where part of this catch can hype started) on the roads and the many of these motors are running well past 250,000 miles without a catch can.

The cars have a 100,000 mile powertrain warranty and that includes mechanical failure of the engine. Trust me when I tell you that there are not reams of data (not even pages of data) on cars coming up lame because of oil at the MAF. It just isn't the problem that the "internet" makes it out to be. When you ask a GM Powertrain engineer about a catch can the reply is that the only thing you get is added weight.

In looking at the extra effort and added cost that went in to the Stingray, do you really believe for one second that if a $20.00 part attached to the engine would improve reliability, limit warranty claims and replacement costs, that GM wouldn't have put it on if it was necessary as part of their evaluation?

Every single GM engineer that I have spoken with told me in one form or another that a catch can is predominately a "gimmick" device created by tuners looking to make a few extra bucks on their engine modifications.

As a by-product of the PCV system, excess oil vapor is recycled to prevent it from leaching out in to the environment. It will condense back in to liquid if the temperature and environmental conditions are right. A catch can is an oil separator device. It allows the heavier oil in liquid to condense in the bottom of the can and only pass the air (gases) back. This is basically the same thing that is happening at the front of the MAF where most of the oil can be found.

The theory is that this oil in the intake system will collect on the valves and in the cylinders and cause excess carbon deposits. The catch can will reduce (not eliminate) oil pooling in the MAF.

Where the plan breaks down is that there aren't thousands of cars detonating because of the oil. As I told you on the phone, This isn't new. The engines are designed to deal with a quantity of oil mist presented via the intake.

You asked what I should tell the customer, my answer is I'm not sure because I don't know what his question is. If the question is is this normal? The answer is yes. If the question is should I put a catch can on? The answer is what ever makes you feel better. If the question is do I need a catch can? The answer is a resounding no. If the reply is that they saw it on the internet, apologize politely and tell them virtually every thread about it has started with a vendor selling a product or a consumer that was fooled by the hype and trying to make themselves feel better about their purchase by getting others to agree with them.

If he has concerns about his condition he should take the car to his dealer for evaluation.

Here is my standard response to the dozens of emails I get each year with a link to a thread like you posted (and often, that very same thread).

Simply stated, absolutely not on the catch can. It simply isn’t warranted for any street driven car. We can talk in more detail about it tomorrow and Dan will appreciate it as I’ve all ready had this conversation with him as well. Since the advent of the PCV system, cars have released some oil in places where it wouldn’t normally have gone in a fully sealed system. It ends up in vapor which condenses back in to liquid form in the intake path. As a result of that, the system is designed to ingest and subsequently digest some extra oil. Higher revving produces more oil and repeated higher revving (drag racer, track duty car, etc.) would be in the realm of uses that I might consider adding the can. Daily driving, occasional back road romp or stop light to stop light burst, not so much.

With all of that said, they won’t hurt anything. For those that don’t want to take my word for it, can feel comfortable adding it but it won’t make an appreciable difference in the life of the motor or the efficiency of the system.
If you dig deep enough in to forum information about catch cans, all roads generally lead back to a performance tuner, aftermarket part supplier or fabricator who has a vested interest in selling catch cans." Stingray Consultant


Mike Furman ~
"Be kinder than necessary, for everyone you meet is fighting some kind of battle"

 

Can't argue with logic presented by Glen e thread.

 

I firmly disagree, the only reason General Motors doesn't put on a catch is because of the EPA. There is plenty of evidence that if oil gets on the valves of the direct injection engine it will cause problems.
You can lead a horse to water.

 

I get that much after every (50 miles) drive and I drive normally on the freeway. It may not be "needed", but for me, and after seeing this oil and where it would of been going, I find reassurance in knowing that I have a
(by RX) catch can. Btw, it added approximately 3 lbs of "extra" weight.

 

This is one of those hot-button issues that may be more a matter of faith than science at this point. The fact that a catch can catches a little oil is meaningless .. oil vapors have been fed back into the combustion chamber for many years. There's no doubt that this happens. The only question is whether, in a direct-injection engine used for 'normal' driving, there will be sufficient buildup and coking on the intake valves to cause a problem, in the absence of the gas vapors that typically clean those valves in non-DI engines.

I don't know yet whether I'll install one or not. I think I'll have to drive the car (which hasn't even been delivered yet) for a while and see what the intake looks like after a couple of thousand miles.

But the whole situation has made me wonder whether the intake valve itself is becoming obsolete. In these engines all it does is let in air .. and requires the entire cam lobe-lifter-rocker-valve train to do so. Makes me wonder why we can't directly inject air as well as fuel, and get rid of the whole intake valve system ..

 

Yup I agree, there have indeed many so many threads about these catch cans yet we haven't seen anyone pull the intake after x thousands of miles to validate any issues. You'd think by now someone would have pulled, took a look and snapped a picture. Hopefully someone will soon. In the meanwhile, I'm on the fence with installing one. It's not the money, just the clutter as Glen mentioned. If it's not needed, I'm not adding it. But sure would love a peek into a seasoned intake to verify! Jerry hurry up and get your car, put some miles on her and snap a pic!!

 

I agree with wait and see if there is a problem. Right now it is pure speculation with a lot of fuel thrown in the discussion by one trying to sell product without at lot of proof for the LT1.

I ordered one from Elite, and the next day cancelled the order. I am still on the fence and caught my balance once already.

 

You snooze you loose. Even if a problem would be covered under warrantee I don't want my engine torn down. For $150 I think it is cheap insurance and sure won't hurt anything.

 

I don't believe it's either needed or warranted. I'll pass.

 

The reality check problem I’ve always had with catch cans is that as far as I know, not a single car maker in the whole world uses them, not even the ultra high performance and price guys like Ferrari. They aren’t even used on diesels, all of which are direct injection, which kind of knocks out the C7 DI worry. So do I go with the unanimous vote of all the powertrain design engineers of all the world’s car makers, or the postings of some internet engineers and catch can salesmen. Hmmmm. Doesn’t seem like a tough choice. Yes, they catch a bit of oil, but the “nobody uses them” evidence strongly suggests that essentially the oil they catch would have blown past the valves and burned harmlessly in the cylinders, as indicated in the lengthy post by the GM guy. Remember, oil has a higher concentration of detergent than gas, so it’s not as though going to DI in the C7 eliminates all cleaning capability. And the comment about no catch cans because of the EPA??? Huh??? Cleaner engines give lower emissions, so if catch cans really meant cleaner engines, EPA would not only allow them, they’d require them. Having said all that, if you're a catch can fan and using them makes you feel better, fine, go for it. As several have said, they can't hurt anything. I'm not trying to throw rocks at anyone. I'm simply saying catch cans don't meet my own personal reality check criteria.

 

LDB great points. Plus DI engines been around awhile so I don't see the need to drink the Kool Aide and waste my money.
My thoughts. GM has a engine warrantee that will cover any damage on the car. For me it will be sold long before the warrantee is up so it's not my problem.

 

Besides it's fun spending money on our toys!

 

I don't know enough to choose a side in this debate. But I have a few observations.

1. To a degree, everything is linked. Change something in a system and it will have an affect somewhere else. Perhaps a catch can would cause issues in something else that has prevented GM or other manufacturers from using it.

2. I think a compelling reason for manufacturers to not use them is that it would be something owners would have to maintain very regularly, and that goes against the trend of making everything maintenance free.

3. Adding onto #2, they'd have to explain to their customers why their engines are blowing this oil out and they need to dump it (and where can you dump oil safely and easily?). That would be some pretty tricky PR to say the least, and I believe one of the biggest reasons no OEM uses them.

4. The engineer's comment that "do you really believe for one second that if a $20.00 part attached to the engine would improve reliability, limit warranty claims and replacement costs, that GM wouldn't have put it on if it was necessary as part of their evaluation? ... well, yes. How much was that ignition switch part that's caused millions of recalls? Even pennies in cost are huge for auto manufacturers, so I can definitely see GM doing a cost/benefit analysis here and deciding the cost is too much (assuming that was the only issue).

5. GM's 3.6 V6 has been DI for 4 or 5 years now, has anyone heard of valve issues? I haven't, but I haven't been looking either

6. Since the new pickups have a similar DI V8, and since they sell shitloads more of them and they get driven tonnes of more miles than a Vette, I suspect they'll be the canary in the coalmine to see if there's going to be any issues.

 

First and foremost who can say for sure that that article was actually written by someone in GM? I find it hard to believe that article came from GM.



Secondly GM does have catch can on LS3 Camaro 1LE clean side oem if I remember correctly.

Lastly do some research on cleaning your top end and that process I will stick with the old cheap catch can....huh never seen good one for 20 bucks.

 

seen dozens of threads in ls3 and lfx engines .....camaro forums where people have documented the oil deposit issues. They are DI engines too.

 

not your problem until after 100k?

 

Different situation. With the ignition switches, I think the “guys in gray suits” just figured it would go away. With something like a catch can that allegedly would reduce maintenance costs, that would strictly be a bean-counting, cost/benefit analysis. Cost, say $30 per car. Will it save $30 per car in warranty costs? Yes/no. They, and their counterparts at every single other car maker in the world, concluded no. To my mind, that’s a powerful statement that value of catch cans in terms of lower warranty claims to the car maker is very clearly and obviously less than $30 per car. If there was even the slightest doubt, then at least some makers would use them. The fact that none do shouts loudly to the heavens that there is absolutely not the slightest doubt whatever.

And as far as the comment by someone else that they are not really that cheap, I’m not talking about cost of installing one after the fact. I’m talking about cost if installed in all cars on the assembly line. It’s a couple of hoses and a small vessel. $30 is generous. Actual cost would probably be more like $10 or $20.

 

As LDB correctly pointed out GM didn't just invent the DI engine. The new GM engines aren't the canary. Diesels have been DI forever, and they don't have catch cans, and they don't have the problems the internet engineers keep yelling The Sky Is Falling about.

It's kinda like the internet oil engineers that say you must change your oil a lot more frequently than the DIC says. It can't hurt, except to your wallet. I'll spend my money on things that matter. YMMV.