Do we really NEED an OCC?!

Assemdew

2020 CX-5 GT w Premium PKG
First of all, welcome and thanks for joining up @Assemdew! Once again the awesome Community here has jumped in to answer questions and provide input...You’re in great hands, enjoy the Forums!

Ps...I think you mean “Forum/Forums” when you say “thread”. This is a thread posted in the CX-5 Forum (CX-5 Engine & Transmission Sub-Forum to be more specific). :)
Thank you so much! Yeah, it often confuses me. But here we go The CX-5 sub-forum :)
 

Assemdew

2020 CX-5 GT w Premium PKG
IMO an OCC is not really required depending on your driving habits. Temp extremes and short drives can lead to more blowby than usual. The car has an oil separator and PCV valve, plus everything that @ceric mentioned. Use engine oil that meets the OEM spec, and press the accelerator a little harder every once in a while to help the engine burn up some of the deposits. I had an 08 IS250 that should have been affected by carbon build-up, but I suspect my driving habits delayed it long enough for me to never have to worry about it.

Regarding warranty, I'm unsure if it voids it or not, but most of the time the OCC can be installed in a way that is easily returned to stock, in case you do need to make a claim. Because of this, I've installed a no-name Aliexpress OCC on my engine just as a redundancy. So far it hasn't caught any blowby on my 2.5 turbo, but others who installed OCCs have reported catching some blowby.

CorkSport sells an OCC. They come with instructions for installation. CorkSport also sells a valve cleaning tool kit, but you'd need to contact them to see if it would work for the 2.5L engine.
Thank you for your reply. I appreciate the info. Unfortunately, OCC will void the warranty. They consider it as an engine mod lol. But the good thing that I might install it as you mentioned maybe with a couple of plastic zip ties and reinstall it whenever I visit the dealership. CorkSport OCC seems a decent design for a catch can, yet simple but I assume it is doing its job. I surfed their website but I couldn't find an OCC for the regular 2.5L Skyactive motor. I have to ask if the Turbo ones will fir my regular 2.5L. Also, why do you think you haven't collected any oil in yours? Do you think it is just because of driving habits? Or maybe the installation position? Does your OCC have an internal filter?
 

Assemdew

2020 CX-5 GT w Premium PKG
Ill just have to chime in on the "does X void the warranty?" question.

Modifications of any sort from factory specifications / configuration are always a slippery slope. Does your oil catch can void the braking system warranty? No.

Does the oil catch can void / invalidate / cause hassle for engine warranty? perhaps. But depending on how it is installed / configured - it could be easily removed before warranty work. It really is up to the local dealer on how much hassle they will give the customer for modifications. OCC is a low risk modification with an easy reversal process should you be worried your dealer is not "mod friendly".
Thank you for your reply. I completely agree! It is a slippery slope! Do you think performing a regular oil change at the dealership with the OCC installed might affect the warranty? I mean if they saw they gonna report it anyway? Or it has to be a warranty work like major maintenance to report the OCC by the dealership?
 

Assemdew

2020 CX-5 GT w Premium PKG
Our Chris_Top_Her has been using a catch can for many years. You’d be amazed how much blow-by his catch can caught. No wonder they saw so much deposit on intake valves whoever took the intake manifold out like felixd and Chris_Top_Her.

Video Cleaning Intake valves CX 5 Skyactiv Gasoline engine
Thank you for your reply. Yeah, I have seen that post! One of the reasons that made me ask the question in the first place? How about your car? Have you installed an OCC? Is it something concerning you?
 

Assemdew

2020 CX-5 GT w Premium PKG
Yrwei52,
I see the point. People look at how much junk got caught inside the OCC and immediately think it works. True, but how effective? Does it reduce 1% of deposit or 90%? No scientific data. Someone (I cannot find the source now) did an OCC and checked the deposit again after a few tens of K miles, and he did not see much improvement over w/o OCC. That is the counter arguement.
So, I am saying that it is not a matter of whether OCC works or not. It does, but how effective?
That is the question we should be asking.

If one can do the following test, that would be very helpful.
1. drive 30K, check carbon deposit
2. clean up fully, install OCC. Drive 30K again, check deposit
Compare the pic between #1 and #2.
That should be convincing. To me, at least.
I completely agree with you. 100%. There is no well-documented approach to whether or not the OCC is reducing carbon-buildup and by how much!! But here is my catch, even though there is no real-world numbers, at least any junk trapped on that OCC is not traveling back to your engine. I understand that there might be some junk traveled back to the engine even with the presence of the OCC, but hey man whatever it traps in not going back! What I mean is a thing better than nothing!
 

Assemdew

2020 CX-5 GT w Premium PKG
I’d use Top Tier gas (Shell only to me) and the latest SP / GF-6 oil trying to prevent those blow-by carbon deposits.
I use the top-tier British Petroleum (BP) gasoline. But I have no idea about the SP/ GF-6 oil. I am new to this whole thing lines of synthetic oils. I regret buying a three oil changes package when I first purchased the car. Now I am stuck with their oil specs, I don't even know what crap they are going to put in my car by the next oil change.
 
:
2018 CX-5 Sport
Thank you for your reply. I do live in the rust-belt unfortunately. Do you have any recommendations for DIY for undercoating? I honestly do not want to be ripped every year going to the shop to undercoat the car. Thanks, man!
I use fluid film. I don't indiscriminately spray the entire undercarriage, I spray welds, parts that forum members showed rusty, and any surface rust I see each time I change the oil. I even spray the exhaust pipes and the welds for the hangers. Granted I am not driving a lot these days because of C and my car is garaged, but thus far I don't have much rust under there.
 
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2018 CX-5 Sport
I use the top-tier British Petroleum (BP) gasoline. But I have no idea about the SP/ GF-6 oil. I am new to this whole thing lines of synthetic oils. I regret buying a three oil changes package when I first purchased the car. Now I am stuck with their oil specs, I don't even know what crap they are going to put in my car by the next oil change.
BP is the only gas that I have used so far.
 

Assemdew

2020 CX-5 GT w Premium PKG
I use fluid film. I don't indiscriminately spray the entire undercarriage, I spray welds, parts that forum members showed rusty, and any surface rust I see each time I change the oil. I even spray the exhaust pipes and the welds for the hangers. Granted I am not driving a lot these days because of C-19 and my car is garaged, but thus far I don't have much rust under there.
Thanks for your reply. Would you by any chance tell me what kind fluid film you ise? I see too many sprays out there. Rustoluem is probably one of the most sold one. Last time I went undercarriage, the car was almost completely covered with plastic and plastic covered with kinda soft flooring materials. I will also recommend spraying any rubber, rubbery joints, boots, and basically anything made out of rubber with ATP 205 reseal. It will make your undercarriage rubbers live forever 🤟🏻
 
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2018 CX-5 Sport
Thanks for your reply. Would you by any chance tell me what kind fluid film you ise? I see too many sprays out there. Rustoluem is probably one of the most sold one. Last time I went undercarriage, the car was almost completely covered with plastic and plastic covered with kinda soft flooring materials. I will also recommend spraying any rubber, rubbery joints, boots, and basically anything made out of rubber with ATP 205 reseal. It will make your undercarriage rubbers live forever 🤟🏻
I use the 11.75 oz pressurized cans. I buy a case of 12 and shop around for the best price. Guys with spray guns buy the gallon containers which is cheaper. I will check out ATP 205, I think Scotty K. mentioned that.
Fluid Film
 
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2019 CX-5 GTR
if you are not familiar with "Project Farm" on YouTube you should be. Here is his video on undercarriage protection products:


He does non sponsored real world testing and evaluations. No BS, no filler, and his methods are reproducible at home should you want to verify the results.
 

AVC

:
'17 CX-5 Select
I see the point. People look at how much junk got caught inside the OCC and immediately think it works. True, but how effective? Does it reduce 1% of deposit or 90%? No scientific data.

++ on that observation.

Would love to see some carefully done OCC experiments ON A SKYACTIV; oil type/brand, valve photos before OCC use for XX miles, then media cleaned valves, then XX miles with OCC, all other variables the same.

From what I've read, separating oil droplets is reasonably done, but separating oil mist or vapor is extremely difficult and aftermarket OCC, as a genre, aren't effective. Maybe there are a few really effective OCC designs that use the sintered bronze filters?

I suspect Mazda, fully aware of GDI deposit tendencies, experimented with various oil separator schemes during design and surely have done their own forensic on engines since 2012 and may have concluded that further oil separation effort had diminishing returns, and while the valve deposits on higher mileage engines *looked* terrible, it had little impact on drivability, performance, economy, etc. Has Mazda quietly tweaked their separator design, or is it the same part from 2012, on?
 

sm1ke

Work In Progress..
Moderator
Contributor
:
Canada
:
'18 CX-9 Signature
Thank you for your reply. I appreciate the info. Unfortunately, OCC will void the warranty. They consider it as an engine mod lol. But the good thing that I might install it as you mentioned maybe with a couple of plastic zip ties and reinstall it whenever I visit the dealership. CorkSport OCC seems a decent design for a catch can, yet simple but I assume it is doing its job. I surfed their website but I couldn't find an OCC for the regular 2.5L Skyactive motor. I have to ask if the Turbo ones will fir my regular 2.5L. Also, why do you think you haven't collected any oil in yours? Do you think it is just because of driving habits? Or maybe the installation position? Does your OCC have an internal filter?

I have no idea why mine doesn't collect blowby. It's possible that the PCV and oil separator are simply doing their job. It's also possible that my catch can might have a vapour leak that I haven't been able to smell, or that the bronze sintered filter makes all the difference (mine did not come with one). I have tried two different installation positions, one by the fuse box and another right by the PCV, with no change. My OCC does not have an internal filter.

Regarding removing the OCC for dealer maintenance, I would probably do it. Mine is installed in a way that makes it easy to remove, I just have the remove two clamps, reinstall the tube to the PCV, then re-clamp the tube. CorkSport's installation is designed for a more permanent install, so it will likely be a little harder to uninstall/reinstall before/after each dealer service.
 
There are a lot of these vehicles on the road, I think this carbon build up issue is not an issue as many are making it out to be, some of it what I call YouTube “scares” to get subs, just drive the car, don’t worry about it, I think if it were an issue, there would be A LOT more chatter about it. I know 4-5 peeps with CX5s, and owned for numerous years, and non have had carbon build up issues. I think if it were a widespread issue, you would see class action lawsuits, again, there are a lot of the CX series (SkyActiv) motors in use, and all commentary is see is 99% positive.
 
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2018 CX-5 Sport
I have no idea why mine doesn't collect blowby. It's possible that the PCV and oil separator are simply doing their job. It's also possible that my catch can might have a vapour leak that I haven't been able to smell, or that the bronze sintered filter makes all the difference (mine did not come with one). I have tried two different installation positions, one by the fuse box and another right by the PCV, with no change. My OCC does not have an internal filter.

Regarding removing the OCC for dealer maintenance, I would probably do it. Mine is installed in a way that makes it easy to remove, I just have the remove two clamps, reinstall the tube to the PCV, then re-clamp the tube. CorkSport's installation is designed for a more permanent install, so it will likely be a little harder to uninstall/reinstall before/after each dealer service.
Maybe it is because of the way you drive. Do you drive conservatively?
 

sm1ke

Work In Progress..
Moderator
Contributor
:
Canada
:
'18 CX-9 Signature
Maybe it is because of the way you drive. Do you drive conservatively?

Not really. At least once or twice a day, I wind it out past 4k, usually while merging onto a main road.

I drive in fairly hot conditions in the summer, and extremely cold conditions in the winter. My drive to and from work is about 30-40 mins each way, so the engine always gets up to operating temps, and I never let the car idle from a cold start.
 
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