When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The difficulty with the Elite Engineering post, as well as with others I’ve seen, is that while they document that deposits can form, they do not document the cause/effect link that the problem came from PCV, nor do they document whether a catch can would reduce or eliminate the problem. Other things could be causing the problem, from dry sump reservoir burps, to poorly designed injector timing and/or patterns that get some gas on the valves before they close, to poorly designed EGR systems, to damaged rings with resulting very high blowby rates. And even if it is the PCV system, are we to believe that the catch can removes all the potential bad actors from PCV vapors? I concede that neither I nor anyone else has all the answers. But a whole lot of very bright people with a whole lot of car companies have doubtlessly spent a whole lot of time looking at this issue, and there is still the huge reality check issue that even though they would be very cheap to install on the assembly line, none of them have chosen to install catch cans. So until or unless I see intake valve pictures of two engines driven under the same conditions (or better yet from an engine test cell where we know they are identical conditions) one engine with and one without a catch can, with the catch can engine substantially cleaner, I’ll remain skeptical.
Very good post, you make a lot of sense. The way I see it whatever is causing the problem is a problem. Installing a catch can won't hurt anything. Then again it might not help either
Very good post, you make a lot of sense. The way I see it whatever is causing the problem is a problem. Installing a catch can won't hurt anything. Then again it might not help either
Nothing wrong with your logic either. The catch can risks mentioned in posts 26&27 seem pretty small, so I agree the “can’t hurt” assumption is pretty safe. As long as you go into it with the understanding that while they are proven to catch some oil, they are not proven to reduce intake valve fouling, and you are thus doing it on the basis of “can’t hurt, might help”, I’m cool.
so then what do you do with the crankcase gasses? best option is vacuum pump. next best is vent to atmosphere (like the lmr setup).
Venting to the atmosphere is not only illegal, it is irresponsible. If they are not burned, crankcase vapors represent the single biggest source of pollution from cars. We all have to breathe the air, and the attitude that one car doesn’t matter kind of reminds me of the folks that think they are so important that they can park in fire zones or handicapped spots. As far as a vacuum pump, it’s not clear where you are suggesting it pump to. Is there some sort of system that burns or somehow traps the crankcase emissions without sending them to the engine intake? If not, the former comments apply.
Venting to the atmosphere is not only illegal, it is irresponsible. If they are not burned, crankcase vapors represent the single biggest source of pollution from cars. We all have to breathe the air, and the attitude that one car doesn’t matter kind of reminds me of the folks that think they are so important that they can park in fire zones or handicapped spots. As far as a vacuum pump, it’s not clear where you are suggesting it pump to. Is there some sort of system that burns or somehow traps the crankcase emissions without sending them to the engine intake? If not, the former comments apply.
you have to be kidding me. where did you move to texas from? California? you have people removing catalytic converters, replacing cam shafts, speeding, racing, burning rubber, spilling race gas, creating noise pollution and so of and so forth and you want to tell me that you have concerns with an open crankcase breather??? go back home.
with that said, if you don't want to vent to atmosphere, then don't. all I am saying then, is that there is no solution for you. let your engine drink it's oil mist and have a wonderful day. your catch can isn't helping.
You make good sense. However, I don't see an ignition switch, but rather a push button, to start the vehicle.
My point is that GM may be aware of an oil deposit build up, and that it will take thousands of miles for it to be a "issue". I have seen many valves from direct injection engines caked with burned oil deposits. These engines had 150K to 250k miles of use. I don't believe the sky is falling,
but I feel more at ease.
Heck, my 2008 Z06 had 16 lifters, a new camshaft
(at 26,000 miles) steering rack, A/C pump, 3 seat motors replaced and I hated to trade it for my C7.
That's about how I feel.
Not saying the valve coking with DI is not real, but it would seem if it's as detrimental as some say and nothing is being done about it on a large Manufacturing scale, then maybe, just maybe ...
nothing can be done about it and it is what it is.
Like someone else pointed out, sure the catch can traps some of the oil, but is it actually solving anything or is it just a band aid.
I don't know
Porsche has used air oil separators on the 911, Cayman and Boxter for several years.
It seems that in this case, I’m guilty of doing what I sometimes tease others for doing, namely, taking statements on faith without having direct personal knowledge. A very quick look confirms that Porsche indeed uses them. I also saw in that quick look that Subaru may too, though in their case, it isn’t clear from my quick look whether they are factory installed or a common aftermarket item for that make. Both Subaru and Porsche have flat engines, which would logically have a bigger oil mist problem because their engines don’t have much vertical separation room inside the engine. But given that I missed the fact that at least Porsche and maybe Subaru factory install them, I can’t rule out the possibility that a few others do too. So I ought to add an “almost” to my “nobody uses them” statements.
you have to be kidding me. where did you move to texas from? California? you have people removing catalytic converters, replacing cam shafts, speeding, racing, burning rubber, spilling race gas, creating noise pollution and so of and so forth and you want to tell me that you have concerns with an open crankcase breather??? go back home.
with that said, if you don't want to vent to atmosphere, then don't. all I am saying then, is that there is no solution for you. let your engine drink it's oil mist and have a wonderful day. your catch can isn't helping.
Moved to Texas from Tennessee. The fact is, if you pull the cats and disable PCV, your car emits as much pollution as at least 50, and probably more like 100 properly controlled cars. Cities the size of Houston have thousands of people who are every bit as much car enthusiasts as you are. I’m one of them. If only 1500 of those enthusiasts pulled their cats and disabled their PCV’s, it would be like adding the emissions from 100,000 cars to the city’s already smoggy air. That’s why it’s illegal to remove or disable that stuff. In my opinion, a responsible enthusiast figures out ways to gain performance without generating the pollution of 50-100 cars. The EPA isn’t perfect, any more than any human endeavor is perfect. But it’s the only thing standing between us and mind-numbing pollution like you see in China. Oh, and on your last sentence, you might want to be more careful in the future about formulating your insults. I’ve been arguing against catch cans, not for them, so we apparently agree that they aren’t likely to make much difference.
Moved to Texas from Tennessee. The fact is, if you pull the cats and disable PCV, your car emits as much pollution as at least 50, and probably more like 100 properly controlled cars. Cities the size of Houston have thousands of people who are every bit as much car enthusiasts as you are. I’m one of them. If only 1500 of those enthusiasts pulled their cats and disabled their PCV’s, it would be like adding the emissions from 100,000 cars to the city’s already smoggy air. That’s why it’s illegal to remove or disable that stuff. In my opinion, a responsible enthusiast figures out ways to gain performance without generating the pollution of 50-100 cars. The EPA isn’t perfect, any more than any human endeavor is perfect. But it’s the only thing standing between us and mind-numbing pollution like you see in China. Oh, and on your last sentence, you might want to be more careful in the future about formulating your insults. I’ve been arguing against catch cans, not for them, so we apparently agree that they aren’t likely to make much difference.
I get a portion of my income from custom tuning cars and trucks. enthusiast is probably not the right word for me. I never said I condoned removing emissions equipment, I said that if you want to solve the pcv issue, it is the only way to do it. I also said that there are far worse things people are doing to the environment as well.
and it might help you to communicate more clearly when you're quoting my posts. either way, happy fourth.
Do you think installing a catch can will pollute the atmosphere? If not what would be the harm removing at least some of the oil from the intake?
no it won't hurt the atmosphere.
the oil mist gets on the can and your valves. not the can or your valves. so why string more lines and parts around your engine bay when the net effect at the valve is no different?
these threads always morph out of control, the original question was it is "necessary"....
I don't think so at all but I don't think it hurts anything either...sold mine as I just don't want the clutter or emptying it. Mount one if you want, you're making the vendors money.
I still have some contacts at BMW engineering and asked them recently about "coking valves" - I got an answer I don't understand (nor do I care to) but the statement was:
When we went to DI in the gas engines, "the first year or two we had some coking but it's not a real problem now, as we adjusted the valve overlap and EGR settings"
these threads always morph out of control, the original question was it is "necessary"....
I don't think so at all but I don't think it hurts anything either...sold mine as I just don't want the clutter or emptying it. Mount one if you want, you're making the vendors money.
I still have some contacts at BMW engineering and asked them recently about "coking valves" - I got an answer I don't understand (nor do I care to) but the statement was:
When we went to DI in the gas engines, "the first year or two we had some coking but it's not a real problem now, as we adjusted the valve overlap and EGR settings"
techies please discuss
they are basically saying the coking on their DI engines was not coming from the PCV system but from the other direction, up from the combustion chamber.
maybe they open the valves while the injectors are spraying and it gets fuel on them to clean them with some egr effect from overlap or they are doing the opposite, depending on what they identified was causing the coking.
they are basically saying the coking on their DI engines was not coming from the PCV system but from the other direction, up from the combustion chamber.
maybe they open the valves while the injectors are spraying and it gets fuel on them to clean them with some egr effect from overlap or they are doing the opposite, depending on what they identified was causing the coking.
The coking is caused by oil getting on the valves from the intake. Don't try to invent the wheel.
You're all overthinking this, I have solved my problem, the only thing left is a permanent mounting place, but after driving with it for a few hundred miles it is collecting on average 9-10 ounces per 100miles driven, more is better right? Well that quart per 3-400 miles is in my "catch can" now, all I have to do is get my backyard refinery going and I'll reuse that oil as well..
Here are some pics, I don't want to give away too much as it is proprietary, but I use a spiral wound paper cloth type first stage and an custom inert metal barrier second stage. I will be powdercoating the new containers before installation..
You're all overthinking this, I have solved my problem, the only thing left is a permanent mounting place, but after driving with it for a few hundred miles it is collecting on average 9-10 ounces per 100miles driven, more is better right? Well that quart per 3-400 miles is in my "catch can" now, all I have to do is get my backyard refinery going and I'll reuse that oil as well..
Here are some pics, I don't want to give away too much as it is proprietary, but I use a spiral wound paper cloth type first stage and an custom inert metal barrier second stage. I will be powdercoating the new containers before installation..
After seeing the last post I suddenly realized that I haven't used any oil in 1400 miles. Now after 300 miles I have about 1oz in the catch can. Is it possible that the oil somehow finds it's way back to the oil sump when there is no catch can? I only see it entering the intake and don't see how that is possible, but at this point who knows. If someone really can give a good explanation please pipe in.
You're all overthinking this, I have solved my problem, the only thing left is a permanent mounting place, but after driving with it for a few hundred miles it is collecting on average 9-10 ounces per 100miles driven, more is better right? Well that quart per 3-400 miles is in my "catch can" now, all I have to do is get my backyard refinery going and I'll reuse that oil as well..
Here are some pics, I don't want to give away too much as it is proprietary, but I use a spiral wound paper cloth type first stage and an custom inert metal barrier second stage. I will be powdercoating the new containers before installation..
Classic, great post....I love to see OCD types have a coronary when seeing stuff like this.....well done....and an ONR bottle to boot!
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.
