I don't believe it's going to be a problem until around 60K or better with this engine.
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Engine Catch can
- Thread starter Y0UKN0WITSCHRIS
- Start date
I can live with 60K or better as this would work out to nearly 6 years of ownership for me based on my current driving profile. Chances are my lovely N will belong to someone else by this time anyway.
Happy to hear if anyone of you high mileage users has something to add to this.
Happy to hear if anyone of you high mileage users has something to add to this.
Im scoping my engine this weekend. I have 6k miles and a full weekend at Barber MSP. Will post results.
This will probably my last post besides replying on this thread as I am pretty satisfied with the results I have gotten thus far with gauging how well the effects of a catch can work on these VN models. Information is very straight forward. My VN is now at almost 7K miles. I just did a DIY clear bra install and changed my oil at 6K miles. She is still running smoothly with no issues besides some possible gear grind and tough shifting under full throttle with gears 2 and 3. After changing my oil at 6K miles and capturing oil, the results were sent to Blackstone Labs for analysis. Everything checks out as normal and my fuel dilution was still less than <0.5%. I am now running Amsoil 0w-30 and this was my first oil analysis with Amsoil 0w-30. Blackstone stated that the viscosity is in the 5w/20 range. The captured oil also looked dark but still in pretty good shape. They recommended that I try extending my oil change intervals to 5K which is music to my ears. I also emptied my Mishimoto catch can and there was some apparent oil buildup around the outside of the micron filter (maybe will clean the filter soon?). The can contents were pretty consistent, still a lot of oil with what appeared to be a slightly higher amount of vapor as I am now driving in the winter months (more condensation of vapor because of the cold). I measured out the contents that were captured in the catch can to about 1 TBSP again so roughly 15ml. I also removed what I believe to be the pressure sensor for the intake manifold and temperature sensor for the intake manifold (somebody corrects me if I am wrong) in an attempt to use a boroscope to peak at the valves and noticed both sensors were coated in oil. I was also able to see very small puddles of oil within the intake manifold. Unfortunately with my cheap boroscope, I was not able to see the valves or turbine blades as I had planned. I will leave these images up to somebody else until I can get a more capable boroscope. I say all that to say that there is a good amount of oil vapor in these intake systems no matter which way you slice it. How you want to deal with it or ignore it is up to you. If you don't plan to keep the car past 60k miles you can prob. just ignore it. I plan to keep the car for life so I am being very careful with her besides the clutch dumps
I am confident that a catch can is a good tool to use with this system to help mitigate carbon buildup. Hopefully, we can get some pictures of some valves soon! I will be getting a more expensive boroscope earlier next year. Good luck everyone!
This is all I could get out of the PCV hose. The other hose was clean as a whistle. 4000km. The car had been driven a short distance an hour prior.
Nice. Did you stick to the Hyundai-recommended run-in process or nail it from the get-go?
As much as I could
with plenty of engine braking in the first 20km. The big down hill run from the dealership for many km took care of that: accelerate and engine brake. Certainty not nailed above 3000-3500 asBest I could restrain the darn car - my cherry went pop as soon as brake in done
The amount that is displayed above avayswavay is negligible. Nearly all, would have been re-burnt in combustion.
What Davo01 got from his PCV and CCV hoses is nothing. With a recommended 15K BG valve cleaning interval, there will be little to no accumulation on the intake valves. Thanks @Davo01 for posting.
What Davo01 got from his PCV and CCV hoses is nothing. With a recommended 15K BG valve cleaning interval, there will be little to no accumulation on the intake valves. Thanks @Davo01 for posting.
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so, to summarise to not that enlightened individuals as I am, not that big of a need for a catch can?
I am somewhat surprised at my results - I do my fair share of 5km drives. However, those short trips are serial trips with short stops in between so the car never cools down between trips. If that makes sense lol. It’s sorta like a longer trip.
I am still thinking of a can (precautionary as per R VelosterN) and have one on order that I linked to here ages ago.
What I don’t get is how / why they join a 9mm barb and a 15mm barb *with a single hose* lol. That and how the frack I get that second clip off - it’s buried so deep.
This is simply not true without supporting evidence. I have tried hard in this forum to provide as much real world data as possible. The oil captured has to pass over the valves before being re burnt meaning it will collect on the varnish of our valves and cake on. We have posted pictures of carbon buildup on Pistons and valves . The oil is coming from somewhere. We have discussed if it's more from the breather side or the pcv side . But to say the oil captured is neglible without evidence keeps leaving me scratching my head. Hyundai does not recommend valve cleaning at short intervals or to my knowledge any other manufacturer including Volkswagen . We have determined that by cleaning in short intervals we can possibly prevent this issue. But that's enthusiasts going above and beyond the manufacturer. I mention volkswagen because I have experience of extreme carbon buildup with their direct injection engine platforms. To the normal consumer a carbon clean at any short interval is leaps and bounds beyond the type of car maintence they would normally do. Car manufacturers do not mention carbon buildup issues in order to sell cars. You get the benefits of flexibility of tuning , power, and fuel efficiency with DI , But without dual direct and port injection your valves will get caked. It's not a matter of if it's a matter of when . The Hyundai platform is the same as we have already seen evidence of carbon buildup on our valves . It's just a matter of choosing how one wants to deal with it. You can wait till 60-80k miles to do a clean that's fine . It will be very expensive especially at a dealership which will charge $600+. I do understand people want to think of these issues as being solved by smart engineers but that's simply false. Manufacturers cut corners to make profit . They are large orgs. If you don't plan to keep the car don't worry about it. But any DI car will get carbon buildup on valves in order to comply with US emission standards. I am not trying to make it sound like this is the biggest deal in the world . Especially if you have $500 bucks to burn to do a professional cleaning. But caked on carbon changes the entire Dynamics of how air enters the motor. It will not operate optimally. I'm not sure how the content of oil I captured is "negligible". Please provide supporting evidence.
Depends on your take . I believe the larger point is how prepared are you to deal with carbon buildup. It's not a matter of if, it's a matter of when. If you are going to sell the car in 5-6 years don't worry about it. Catch can is just another method to prevent carbon buildup . I don't consider it purely preventative In the sense that you can run it if you want but you will be fine without it. One way or another you will have to deal with the issue unless you will sell the car before 100k. Other individuals are not planning to run a can but are going to do chemical cleaning at 10,15,20k mile intervals in order to clean their valves. Unless chemical cleaning is also just purely "preventative" I don't believe it's accurate to determine a catch can as purely "preventative" it's necessary to deal with the carbon in one way or another. The logic is if you do chemical cleaning at short intervals you will be able to totally clean the carbon off the valves . If you wait till 60k the carbon will be so caked on that chemical cleaning will not be enough. You will have to do a manual cleaning (scrubbing the valves with an abrasive tool). You will have to remove the entire intake manifold in order to access the valves in order to do this method of cleaning . At 60k I was quoted $700 to do this type of service on my MK7 VW GTI. The carbon buildup was so bad I had multiple missfires and a cylinder totally shutdown. Not tryna fear monger. Simply playing devil's advocate and trying to educate while posting supporting evidence. All that oil I captured would blasted your valves . It's just a fact lol. The air AND oil has to pass over the valves in order to be burned .. lol
Catch cans are simply effective and cheap methods to aid in the process of capturing un-burnt oil in the combustion process . A tool that manufacturers could easily implement in modern cars but people would fail to remember to empty them and destroy there engines when it's flooded with captured oil. One has to rememeber you have people out here who don't even know they have to change their oil in their vehicles . This is important to remember when you are selling to the masses. A catch can will not totally cure the carbon buildup issue but it will assist. I have seen some evidence of lab testing in regards to chemical cleaning and showing its effectiveness. Some work betters than others but if there is less carbon on the valves then of course it will be easier for the chemical cleaner to do its job. I will take a cotton swab and also swab the inside of my pcv line when I get the chance . But I am already fairly confident in my assessment of carbon buildup on these platforms from seeing photo evidence of Excessive carbon Buildup on boosted cars , the oil amounts I have captured per 1000 miles , seeing pools of oil in my intake manifold and my breather and pcv lines being coated in oil. Every vehicle is different and everyone has different driving habits. So test your vehicle . Short driving distances before the engine is fully warmed up will cause the most oil to slip by piston rings as rings and cylinders have not warmed up to operating temps in order to best seal combustion chamber. I have also had my oil tested twice and my engine has only trace amounts of blow by, less than 0.5%. Even with that low value you see how much oil I captured . I even did a water test to show that what I captured is almost entirely oil and combustion gasses. One has to rememeber that blow by only increases as engines grow older and you have wear on the cylinder walls and piston rings , so you will only have more blow by. A new car is best sealed as possible in regards to the combustion Chamber after the break in period is complete. I believe a boosted cars with more blow by is an "okay" equivalent to the effects of an old engine with significant blow by. I would love to debate this lol.
Not as badly as you think. You are talking about two different engine in the Hyundai and VW. The VW and Honda engines being the far worst. The VW engine has considerable blowby, which causes the coking problem far worse than the Hyundai 2.0T Theta II.
I can clearly see you're particular overreaction based upon the VW engine. I believe others have also. Not all GDI's are alike and so far, the Hyundai 2.0T Theta II isn't a problem. With a fuel dilution of less than 0.5% the amount of fuel/oil/water vapor is not a significant amount, nor is it near the fuel/oil dilation levels that most VW engine have.
Cleaning with the BG system at 15K intervals is not expensive and just good preventative maintenance for the long run.
The supporting evidence is out there from other VN owners. Some have actually removed their CC systems altogether. The amount they're collecting is even less than what you've collected. Common sense and understanding about fuel/oil dilution levels is necessary and not jumping to on unsubstantiated claims. Frankly, your claims do not favor the use of a CCV/PCV catch can system. Maybe if you were having twice or three times the amounts per oil change but not at the insignificant amounts you've demonstrated. Also such a system would be need if, a 3.5 percent fuel/oil dilution was found in Oil Lab Analysis, each time you tested. You're not coming close to this level of dilution.
It's not just the oil that cokes the valves. It's the combination of fuel/oil/water vapor. You're just not producing enough fthis type of dilution. The oil you're catching will generally be moved back thru the PCV to be re-burnt. The engine was designed to reburn this amount of fuel/oil/water/vapor. The majority of what you're collecting is comparatively small and the valve cover filtration utilized on the 2.0T Theta II, is working quite well.
Based upon what you shown in only one oil analysis, you can actually be changing the oil every 5K miles, based on the lab results. I believe this is what the Blackstone lab suggested as well in the comments. You're going to the extreme, based upon your past experience. Understandable but not necessary.
The use of a catch can for either side is optional with this engine, unless you're utilizing the car for a lot of short, slow speed trips and in stop and go traffic. You're attempting to convince other owners it's the best and cheapest thing to do to overcome a possible coking issue. It's clearly it's not, based upon your own oil analysis provided by Blackstone Labs.
I've had similar results in oil lab testing. In comparison it just doesn't warrant the use of a CCV or PCV catch can. So it then comes down to, individual choice to utilize one or not. Otherwise optional.
Now, no one has equaled or surpassed 60K-80K miles with this specific engine. So it remains to be seen how much actual intake valve and piston coking will occur. If owners are following a good regular preventative maintenance schedule ie; "changing the oil at no more than 5K intervals. Utilizing high quality spec synthetic oils. Running top tier high test fuels and have regular valve cleanings," I see no foreseeable issues. You experienced these issues in your VAG engine obviously. It's my personal observation, you weren't adhering to what is specified above.
Your speculation about this specific Hyundai engine, are without a basis of factual information
Most members here are clearly aware of how a GDI and multiport fuel injections engines work, so we can dispense with the continuous repetitive rehash of researchable internet information.
You have no data to support your belief. You haven't included any viable long term personal data about your own VN. You have included any comparative data for NA engines verses, turbocharged engines. It's merely personal speculation.
I understand you had a bad experience with the VW engine and it cost you some money you weren't expecting or didn't have at the time. However it's this particular past experience that is driving you to utilize a PCV catch can now. It doesn't mean you'll experience it with this particular Hyundai engine. As the miles wear on from both the VN and i30N, everyone will be made aware of any such issues, if they become prevalent.
You're basing the need for a catch can upon a bad past experience with the VW. I certainly don't believe either the CCV/PCV catch cans are to be considered requirement or will provide any additional preventative benefits, if a normal maintenance schedule is completely by the owner.
I'm also seeing another issues here. You've stated it's a good tool to preclude or circumvent such issues. Which sound distinctly like a means of avoiding the expense of regular maintenance. You obviously didn't adhere to a good maintenance schedule with the VW and learned it cost to keep a good maintenance schedule. It cost you $700 + @60K miles, for the lesson. Now you're attempting to find a cheap way of nullifying such a long term cost and avoiding the expense of the performing regular maintenance as well.
Such old habits die hard. IMO thru reading your comments, I see a trend of complacency and procrastination of performing regular maintenance by looking for a short cut. I see by your own comments and continued insistence of trying to convince yourself and others this is the way. Frankly and IMO you've exposed the truth of the matter pretty clearly. Owning a car means monetary responsibility beyond the initial costs, insurance, fuel, maintenance etc. Owning one takes a big chunk out of your salary, especially if you're not making that much to begin with.
Sorry, you're going to have to budget maintenance costs to follow a good maintenance schedule. It's going to cause you some personal inconvenience monetarily and will certainly take away some of your party and fun money. Nevertheless, you're going to have to do so, if you want to keep the car in good condition and avoid more of the same expenses you had with the VAG.
I can clearly see you're particular overreaction based upon the VW engine. I believe others have also. Not all GDI's are alike and so far, the Hyundai 2.0T Theta II isn't a problem. With a fuel dilution of less than 0.5% the amount of fuel/oil/water vapor is not a significant amount, nor is it near the fuel/oil dilation levels that most VW engine have.
Cleaning with the BG system at 15K intervals is not expensive and just good preventative maintenance for the long run.
The supporting evidence is out there from other VN owners. Some have actually removed their CC systems altogether. The amount they're collecting is even less than what you've collected. Common sense and understanding about fuel/oil dilution levels is necessary and not jumping to on unsubstantiated claims. Frankly, your claims do not favor the use of a CCV/PCV catch can system. Maybe if you were having twice or three times the amounts per oil change but not at the insignificant amounts you've demonstrated. Also such a system would be need if, a 3.5 percent fuel/oil dilution was found in Oil Lab Analysis, each time you tested. You're not coming close to this level of dilution.
It's not just the oil that cokes the valves. It's the combination of fuel/oil/water vapor. You're just not producing enough fthis type of dilution. The oil you're catching will generally be moved back thru the PCV to be re-burnt. The engine was designed to reburn this amount of fuel/oil/water/vapor. The majority of what you're collecting is comparatively small and the valve cover filtration utilized on the 2.0T Theta II, is working quite well.
Based upon what you shown in only one oil analysis, you can actually be changing the oil every 5K miles, based on the lab results. I believe this is what the Blackstone lab suggested as well in the comments. You're going to the extreme, based upon your past experience. Understandable but not necessary.
The use of a catch can for either side is optional with this engine, unless you're utilizing the car for a lot of short, slow speed trips and in stop and go traffic. You're attempting to convince other owners it's the best and cheapest thing to do to overcome a possible coking issue. It's clearly it's not, based upon your own oil analysis provided by Blackstone Labs.
I've had similar results in oil lab testing. In comparison it just doesn't warrant the use of a CCV or PCV catch can. So it then comes down to, individual choice to utilize one or not. Otherwise optional.
Now, no one has equaled or surpassed 60K-80K miles with this specific engine. So it remains to be seen how much actual intake valve and piston coking will occur. If owners are following a good regular preventative maintenance schedule ie; "changing the oil at no more than 5K intervals. Utilizing high quality spec synthetic oils. Running top tier high test fuels and have regular valve cleanings," I see no foreseeable issues. You experienced these issues in your VAG engine obviously. It's my personal observation, you weren't adhering to what is specified above.
Your speculation about this specific Hyundai engine, are without a basis of factual information
Most members here are clearly aware of how a GDI and multiport fuel injections engines work, so we can dispense with the continuous repetitive rehash of researchable internet information.
You have no data to support your belief. You haven't included any viable long term personal data about your own VN. You have included any comparative data for NA engines verses, turbocharged engines. It's merely personal speculation.
I understand you had a bad experience with the VW engine and it cost you some money you weren't expecting or didn't have at the time. However it's this particular past experience that is driving you to utilize a PCV catch can now. It doesn't mean you'll experience it with this particular Hyundai engine. As the miles wear on from both the VN and i30N, everyone will be made aware of any such issues, if they become prevalent.
You're basing the need for a catch can upon a bad past experience with the VW. I certainly don't believe either the CCV/PCV catch cans are to be considered requirement or will provide any additional preventative benefits, if a normal maintenance schedule is completely by the owner.
I'm also seeing another issues here. You've stated it's a good tool to preclude or circumvent such issues. Which sound distinctly like a means of avoiding the expense of regular maintenance. You obviously didn't adhere to a good maintenance schedule with the VW and learned it cost to keep a good maintenance schedule. It cost you $700 + @60K miles, for the lesson. Now you're attempting to find a cheap way of nullifying such a long term cost and avoiding the expense of the performing regular maintenance as well.
Such old habits die hard. IMO thru reading your comments, I see a trend of complacency and procrastination of performing regular maintenance by looking for a short cut. I see by your own comments and continued insistence of trying to convince yourself and others this is the way. Frankly and IMO you've exposed the truth of the matter pretty clearly. Owning a car means monetary responsibility beyond the initial costs, insurance, fuel, maintenance etc. Owning one takes a big chunk out of your salary, especially if you're not making that much to begin with.
Sorry, you're going to have to budget maintenance costs to follow a good maintenance schedule. It's going to cause you some personal inconvenience monetarily and will certainly take away some of your party and fun money. Nevertheless, you're going to have to do so, if you want to keep the car in good condition and avoid more of the same expenses you had with the VAG.
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Innacurate. The VW engines which were ran in the MK7 GTI's did not have substantial blow by lol. They were also trace amounts less than 0.5% or 1%. If one is not capturing large amounts of oil in there engine don't worry about it. Test your own engines . As I've mentioned I've seen and posted carbon buildup on these platforms on both Pistons and valves . If you weren't worried about carbon buildup at all not sure why your doing a chemical cleaning .
Multiple innacurate statements in this response here . I'm not trying to convince anyone of anything . I'm simply showing my results . I haven't see you post any evidence of blow by or captured unburned substances from your own engine. I never once said a catch can was mandatory lol. Not once lol so idk where that statement is coming from all I'm saying is that the fuel oil combination flowing over these valves are not neglible . It's simply really a port injected car will wash all substances off the top of the valves . DI you do not get this. So you go from washed and cleaned valves to gunk flowing over them . Meaning that the amount of oil I captured is significant in relation to a port injected car which has washed valves every time gasoline is sprayed into the combustion chamber . There's not alot of evidence for high mileage cars bc these models are new. So what is the next logical means we can use to try and determine if carbon buildup will occur? Boosted cars. The logic is simple . It's common sense . Multiple users have also stated that boosted cars will experience blow by issues . Why? Because more boost pressure causes more blow by. This leading to more gunk flowing over the valves . Again , blow by increases as engines age. So as more blow boy occurs in your engine over a substantial amount of time the more gunk will flow over your valves . We're not talking about somextreme 35 psi of boost here . We're talking like 20-25 psi. As our engines only boost to a Max of 15 psi of boost at very low RPM stock. Finally other members have posted identical results to my own in terms of oil capture in the American forum. Test your own cars. If you do not feel the need to take steps don't. But don't say my results are neglible with zero evidence and zero testing of your own lol.
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Finally you cannot assume everyone understands the concept of GDI Turbo engines as clearly peoples are in here asking questions lol. The only solution to no carbon buildup in GDI engines is port injection and direct injection . Auto makers know this very very well. That's why you see next generation vehicles have both. The two largest auto makers in the world Volkswagen and Toyota are both going this route. So clearly it is still a problem and clearly simple internal baffles do not solve this issue lol. This is simple . Let's not over complicate things guys . But yea .. test your own engines lol
Ah also unburned substances are re rerouted to be burned again in the combustion chamber only because of emission standards . Not because they have perfected DI in relation to carbon buildup.. If it was so simple large auto makers would not be going to port injection in addition to direct injection like Toyota and Volkswagen . These vehicles are already on the road overseas..
And finally if you go to any Hyundai dealer service department they have huge posters of carbon cleaning service right besides oil services , brake services , tire rotation services. Again this is an issue that has NOT been solved. Simply put all GDI engines especially turbo applications will experience carbon buildup . Can a manufacturer mitigate it ? Make it better ? Yes , but eventually it will rear it's head . This is true of any manufacturer. The engineering itself is flawed . Auto makers constantly have to make sacrifices in terms of engineering to meet safety and emissions standards . That's why our modern cars have gotten so heavy , so complicated , and so expensive . Carbon buildup is a trade off for all the benefits of direct injection .