Oil CATCH CANS! (FM Live)

This week on FM Live, Brandon will be talking us through air-oil separators, commonly known as "Catch Cans". Catch cans separate oil from your recirculating systems to keep contaminants from re-entering your engine, but how do they work? Do you need one for your Miata?
Moroso Air/Oil Separator:
www.flyinmiata.com/default/mo...
Verus Air/Oil Separator:
www.flyinmiata.com/default/ve...
Please let us know what you'd like to see us talk about in future videos! Original live video recorded 7-1-21. Join us every Thursday on Facebook at 2:00 PM Mountain time for new live content, and visit our KZbin channel to see all our Miata videos!
Flyin' Miata is the world leader in Miata performance. We offer a wide range of parts for all years of the Mazda MX-5 Miata.
www.flyinmiata.com​​​​​​​​​​​​​
970-464-5600 • [e-mail]

[@origtwyg]

Thanks for answering regarding the mazdaspeed question. It made perfect sense and is a great next step for my build. Good stuff.

[@patrickfargie1146]

I was just considering getting one earlier today and then I saw this. Definitely looking into it now.

[@2007MXV]

Every ND deserves an air/oil separator.

[@twrcrew8852]

but why do some of them only go between the egr and intake, but this crazy one has to catch oil from 4 different tubes? why don't the other ones catch all 4 ports?

[@dennisswaney644]

Aftermarket catch cans are used very frequently on VW TDIs (and probably other diesels) in California without any problem. Also, the can should be drained at every oil change.

[@wwilliams1358]

At the 8:50 mark, you mentioned the NC and ND have a manufactured catch can. I was thinking of getting an ND2, but I got a deal on an NC3 instead. So my question is in regards to the NC2. If I get the Verus AOS, is the connection points the same as the ND2? Or, should I get 2 separate CC instead? I realize the mounting bracket is for the ND2 however, I'm sure I can figure out how/where to mount it on the NC3. Thank you for your videos...now I want to see more on the NC...LOL!

[@rlhotka]

Brandon, Best one for an NC?

[@cliftonfrey1174]

I first contacted my dealer about the catch can and they referred me to Mazda Warranty department about the catch can and they were the ones who told me I would void my warranty if I installed it.

[@boblast5582]

have you guys looked at the Killer B meshless catch can? really interesting design

[@FlyinMiataVideo]

We aren't familiar with that particular brand. Thanks for the suggestion!

[@danielinacar]

I was so ready to order one but you said you can't ship to california :(

[@mrsluigi9478]

Is there anything you have to replace inside the Verus unit? I remember some Mountune catch cans make you replace a filter every so often, but Mishimoto baffled ones are maintenance free (apart from draining the oil gunk of course). I just bought a Mishi kit for my Focus ST so I'm just wondering

[@FlyinMiataVideo]

No need to replace anything internally in the Verus unit.

[@BoostedNDMiata]

Question about the verus catch can on a forged ND making 16 psi boost. There is talk of crank case pressure bleeding across to intake manifold pressure through the verus under high psi. Is there any validity to the claim and cannot be sealed or just scrapped for a two can system? Just finishing my build and don’t want to install something that may cause problems.

[@FlyinMiataVideo]

This is a very interesting question. We pitched this question to Brandon, one of our engineers. The Verus catch can does have two separate chambers, but they do share a drain. There is the potential for pressure to transfer due to this shared drain, but the Verus includes a PCV valve built into the inlet from the intake manifold. From Brandon, our engineer: "I don't think it will be enough to make a difference, though. Plus, whatever pressure gets through the PCV will go to the bottom of the crankcase (in the ND), which is directly attached (airflow-wise) to the valve cover (i.e., the other side of the catch can). So the Verus does have an additional path for air to flow, but on a stock or two-can setup you'll still pressurize the crankcase by whatever the PCV lets by." Does that help? Please feel free to give us a call at 970-464-5600 or drop our team an email at [e-mail] if you have more questions or want more details!

[@BearWa11ace]

I just got one for my 99 Miata. I felt like it would run cleaner and that can't be a bad thing.

[@FlyinMiataVideo]

It's good preventative maintenance for sure!

[@asmanisg]

Why don't you use 3 port catch can? Some oil catch can users saying about a bad smell while they using this mod.. Is that true or all of this is dependent from the place you install it in the engine bay?

[@egilsaerman8769]

Will this fit with the bigger Washer fluid bottle some (Canadian? Scandinavian?) NA's have? or would i have to move it somewhere else? And thanks for the great vids! 😁

[@FlyinMiataVideo]

Admittedly, this is something we've never tested, so we can't give you an exact answer - sorry! If it does work, fitment will be very close. Luckily, the bracket included with the Moroso kit can be used almost anywhere in the engine bay.

[@egilsaerman8769]

@@FlyinMiataVideo Seems like I'll have to find out. Thank you anyway!

[@scottmason2245]

I watched your video and maybe I' missed something and this may be a dumb question, but if you dont have a breather filter on the drivers side vent tube.......where does it go? Is it tied into the intake of the turbo???

[@FlyinMiataVideo]

The location varies slightly depending on generation, but lets assume you are talking about the NA/NB Miata. There are two lines coming off the valve cover. The first is the line on the intake side attached to the PCV valve that feeds back into the intake manifold. The second is on the exhaust side that feeds directly into the intake tube. Catch cans should be inserted in the middle of the lines, one on each side for optimum effect. This keeps unmetered air from entering the engine, and keeps pressure where it should be. If you have a breather filter in place in either location, then your car has been modified, and one of these lines has been blocked off. This is not ideal for several reasons that Brandon covers in the video. If you need more help, or have other questions, please feel free to give us a call or drop us an email at [e-mail] and someone will be happy to go over the details with you. Hope that helps!

[@scottmason2245]

@@FlyinMiataVideo you answered my question. I now know it goes into the intake of the turbo. Ty for all the awesome information and videos

[@b2bb]

When you say an ND with "fairly low mileage", where the buildup didn't get necessarily worse on the valves.. how many miles are we talking? I ask because I am at 12k miles on my ND2 and just ordered one. 19:30

[@ag4allgood]

Just look at guys who have installed a Super Charger or Turbo on their ND / ND2s. Even as low as 12,000 miles there is significant carbon buildup on the valves.

[@mjmyers]

Any issues with condensation freezing in these during winter conditions?

[@FlyinMiataVideo]

We've never seen this happen. Anything inside the can doesn't matter, and everything going into the can will be heated by the engine and won't be able to freeze while the car is running.

[@punkish7]

any videos available on how to access the hose down by the PCV valve? Looks like it would be very difficult to do, especially for someone that does not do much mechanic work :)

[@FlyinMiataVideo]

You might try watching our full Verus air/oil separator install video. It shows those locations on an engine out of the car, and gives some tips on how to access them for the install. kzbin.info/www/bejne/bV6zm2Owed2epJosi=A3xZXJMmzwWwy_lx

[@punkish7]

@@FlyinMiataVideo perfect, thanks!

[@chrisschneider7727]

Is it a good idea to add steel wool into a catch can to restrict oil and oil vapors from escaping out the breather vent?

[@FlyinMiataVideo]

Most quality catch-cans/separators will come with a mesh, so the additional filler is not needed. Please do not use off-the-shelf standard steel wool. Normal steel wool will rust due to the moisture and cause an even bigger problem in the long run.

[@trangk4771]

@@FlyinMiataVideo would it be a good idea to use stainless steel wool then?

[@bop1051]

@@trangk4771bronze wool

[@user-kn2ec7ud5f]

Do the catch can causing a restriction on crankcase?

[@FlyinMiataVideo]

It's not part of the main airflow for the intake air, so no.

[@ColtonBlumhagen]

Coming from the diesel world we typically would delete the pcv and run a drain hose to either a hole into the frame or just straight to the ground. I’d rather do that then have a can to empty.

[@FlyinMiataVideo]

Yeah, I spent a lot of my career working on diesels and I don't prefer that type of rust proofing on the bottom of my car. 😁 Just because you can, doesn't mean you should.

[@arnoldosu1]

I’ve never emptied my moroso unit. It’s been on for 11k miles/5 years. Is there any potential issues for not emptying that long? Also what would you use to clean it out if there is buildup?

[@FlyinMiataVideo]

If it's not full and you've never needed to empty it, there shouldn't be any harm in waiting that long. If you want to clean it, brake clean or something similar, just make sure it is completely dry and clean before reassembling. Give us a call if you get stuck.

[@arnoldosu1]

Thanks for the quick reply! It’s the Moroso unit with the drain valve on the bottom. It was installed before I adopted the car and I didn’t realize people usually empty them every oil change or so. Would there be any performance indication that it is too full to do its job properly? Perhaps I will just go empty it. I’ll mention this on a 200whp Mazdaspeed.

[@travdripdrip382]

I hooe this gets answered. Pin an NB what about a catch can and then a small air filter on the other side of valve cover? The intake side i guess its called

[@3gsFreak]

Where do you do your live streams?

[@FlyinMiataVideo]

We live stream from our shop to our Facebook page every Thursday at 2:00 PM Mountain time. facebook.com/flyinmiata

[@3gsFreak]

@@FlyinMiataVideo Thanks! Joined the FB page. Great videos.

[@twrcrew8852]

What about someone designing a full fledged old school aftermarket intake manifold with fuel rail JUST for the ND?? 1) It would open us up to the big wide world of aftermarket fuel injectors for extra fueling - for TURBO **(since yall keep talking about how the Direct Injectors falls short)** 2) It would basically be our very own D4-S system and keep the valves clean indefinitely like all the other engines of the past. Papadakis did this for the mk5 Supra and i'm VERY surprised nobody else on the planet tried this for other DI engines. If not all that, at the very least design some type of fuel-sprayer that can throw a mist of fuel into the intake mani like a wet shot of nitrous would be sprayed. they'd inevitably get sucked down past the valves and the same thing would happen as it did in the old days.

[@westbrionage]

I know i'm well out of date, I can see how a catch can would reduce emissions in an emissions test, but do you know if it would even be noticable?

[@FlyinMiataVideo]

We've never tested this for emissions reduction, even tho in theory, reducing the oil fed into the engine should help. We just really like the idea of keeping the engine as clean as possible for as long as possible by keeping the sludge out.

[@westbrionage]

@@FlyinMiataVideo Yeah, i thought they were just for turbo chargers, but you've turned me on to just keeping the engine cleaner. Great to see you still keep an eye on older videos, cheers!

[@mr.adventure559]

How to connect a catch can on a Miata engine with ITB's?

[@patrickfargie1146]

I assume you're still running vacuum from the valve cover to your vacuum block right? I'd just a catch can inline with it.

[@cliftonfrey1174]

My MX5 is still under warranty I inquired about a catch can and if it would void my warranty and Masda said it would is this true

[@FlyinMiataVideo]

We unfortunately have no control over what dealerships will and won't cover under warranty. The catch can does not replace or interfere with any system on the car, so realistically it should not effect your warranty, but some dealerships will possibly give you some hassle over it. If your car is still under warranty and you are still taking it to the dealership for service, we recommend getting their opinion or talking to an alternative dealership before modifying your car.

[@FlyinMiataVideo]

It should be added that, by law, a modification can only void the warranty if it caused the failure. If you install a catch can and your transmission fails, the warranty is intact. If you modify the PCV system and the car suffers a ring failure, that would likely not be covered.

[@philjones5728]

Brandon: why are you so set against a vented catch can? I have a turbo mk1 and run a Mishimoto catch can with 2 in-ports (one from the pcv and the other from exhaust side of the cam cover) and 1 out-port which has a filter. I get no oil deposits on the underside of the hood/bonnet or anywhere in the engine bay. My original pcv inlet port on the intake manifold is capped off as even the best catch can won't catch 100% of the oil/gunk that comes from crank case venting. By routing the exhaust side cam cover vent to the turbo inlet you will get oil/gunk deposits within the turbo/intercooler piping and the pcv side will put oil/gunk deposits into the intake plenum. I would rather have a clean intake and turbo and catch the oil/gunk in a catch can, which seems like a win/win scenario. However, I do 100% agree with you that all ICE cars should have a catch can if possible. Great video BTW!

[@michaelh.9866]

On the blue NA, where did the cowl cover come from?

[@FlyinMiataVideo]

That's a GarageStar piece.

[@hooligantimes9132]

I have faith that them Hiroshima boys have it setup good enough for me.

[@twrcrew8852]

if you saw the threads on miata forums, you'll see that they do not. unfortunately. 8000 mile cars look like 3 pack a day smokers on the valves. so much tar.

[@62Sketch]

What would you do if you are in California?

[@Spazin0ut]

Move

[@judasblewit]

Move

[@kothareddykrishna]

I believe Mazda designed the inlet manifold with baffles. Catch can is not required unless you boosted the engine

[@FlyinMiataVideo]

Brandon discusses some of the pros and cons of the factory system in the video. It still drains the contaminates back into the engine. A catch can completely pulls the contaminates from the system, ensuring any garbage is totally removed from circulation. This is why we still recommend them, especially for the Direct Injection engines.

[@gerardgeer642]

"can catcher" oh jeez

[@FlyinMiataVideo]

The puns were hard to come by for this one lol