Oil Catch Cans Crankcase Pressure, Provent 200 vs Mishimoto vs Universal oil catch can

Are you afraid that an oil catch can will increase the crankcase pressure, spilling oil everywhere? Here is the answer! Check the description as well. If you also wondered what is normal crankcase/engine pressure, here it is.
I was really worried that my oil catch can in my turbo diesel 1.6HDi Peugeot Partner (2007; M59; ~102,000 miles or ~164.000 km) will lead to stress in the engine, i.e. increased crankcase pressure, blown seals, oil will be coming out, etc. This video is a relatively conclusive test that this particular oil catch can (copy of the Mann-Hummel Provent 200) does not increase the crankcase pressure, but others do. For example an universal oil catch can , even with steel scourers does not increase the crankcase pressure, but a mishimoto oil catch can substantially increase the crankcase pressure. The car is similar to a Citroen Berlingo and the engine is the same as in 1.6TDCi (Ford), Volvo, Suzuki, Mini, Mazda3, etc.
If you find this video useful, buy me a coffee: www.paypal.com...
All my car-related purchases: www.amazon.co....
The cheap Mann-Hummel Provent 200 oil catch can is MASO (amazon UK): amzn.to/2YIuJ97 or ebay: ebay.us/lpKALx
The kkmoon baffled oil catch can with the bronze filter (amazon UK): amzn.to/3B0HqQt or ebay: ebay.us/3eD5Eg and is the same as the Mishimoto oil catch can (amazon UK): amzn.to/3hK0uYn or ebay: ebay.us/rDu7rX
The universal oil catch can (amazon UK): amzn.to/3IBdA6y or ebay: ebay.us/bKkoB5
The sensor for crankcase pressure measurement is Bosch DPF exhaust pressure sensor (0-1bar) and the part number is: 0281002772 (amazon UK): amzn.to/3H1H8dp or ebay: ebay.us/6tVVqL
The videos explaining how I did the crankcase pressure measurements are here: • Reading absolute press... and here • Reading absolute press...
The arduino code is included in the two previous videos.
The new Mishimoto oil catch can that is classified as MMBCC-HF and the HF stands for high flow (amazon UK): amzn.to/2NiiY3P or ebay: ebay.us/XfrHY1, but it is quite expensive. Here is the Mishimoto website for this oil catch can: www.mishimoto.... and a bit more on how they designed it: www.mishimoto....
The actual results are here:
Baseline (original intake, no oil catch cans) 1.55mbar
Mann-Hummel Provent 200, cheap steel filter 1.58mbar
Mann-Hummel Provent 200, original filter 1.54mbar
kkmoon (Mishimoto) with bronze filter 6.20mbar
kkmoon (Mishimoto) no bronze filter 2.85mbar
universal oil catch can no steel scourers 2.10mbar
universal oil catch can with steel scourers 2.40mbar
#HDi #CarMods #OilCatchCan
Disclaimer:
Use the information provided in this video at Your Own Risk. More molecules provides this video for informational purposes only and assumes no liability for any damage or loss incurred as a result of the use of the information or tools presented in this video. The information provided here may contain inaccuracies and more molecules cannot guarantee the correctness or reliability of the content.
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[@adrpals2324]

I've heard bad and good thing about catch cans, especially about the pressure in the engine. Your videos is great and a wealth of information.

[@owenhill-vf7ko]

As a 3rd generation mechanic and engine builder I don't use catch cans on my Ecoboost or DI engines. They aren't necessary. Use a good synthetic Oil, change every 5k miles,Tier 1 gasoline, replace pcv valve and coolant at 50k miles and zero problems!!

[@kevinm6283]

The best video and explanation I’ve ever seen. Very well done. And I’ve seen a lot of catch can videos. I run the brass micron filter and ordering the other can in the video right now. Thank you so much.

[@moremolecules]

Yeah, I was always concerned about crankcase pressure and if something will happen using them, hence the video. Basically for my own peace of mind.

[@stugillis]

You think the pressure wouldn’t increase so much in a petrol engine? Thanks

[@kevinoneill41]

Back in 1990 I saw a diesel engine generator with a 2qt paint can as a catch can filled a course fiber. The crankcase was vented straight to the center top of the can. The lid was perferated with what appeared to be knife stabing holes all over the top of the lid. The can was placed in a larger pan with an oil spill pad on the bottom. 😂😂 my guess is that this was better than venting straight to atmosphere. I had to open the can. What I found was amazing. It appeared to be working quite well. 😮

[@seanbrennan4447]

Great to find a channel that has the same car and age as mine :) thanks

[@moremolecules]

Hahaha, I know what you mean. Hope the videos are useful.

[@Thinkforyourselvz]

Thanks mate, as this is something I have been thinking about when I installed a catch can on my 6L LS. This clears it all up for me now.

[@proobuio]

This is nicely done sir. I was wondering why mishimoto added those fancy bronze filters knowing that it would be add more restriction to the air flow. And im glad this answers it

[@steiljeds]

thank you. benchmark data is always best for breaking theories and myths

[@armandomolina8758]

Great information i run that universal can with steel wool. It catches 1oz in 1000miles

[@jplunkett3647]

nice testing and explanation ..... due diligence / research is critical in ANY subject matter ,,, thank you ,,, i am now a subscriber based on this video

[@diylife1688]

very good test important to note that when the provent paper filter is dirty, it blocks considerably, i had this happen on my diesel. My oil was being forced out of my oil filler cap on rocker cover. So much!!!.the metal one not so mucj so if you've got all of these still i would recommend a second vid3o of them all dirty.

[@moremolecules]

Yes, I bet them all dirty will be quite a substantial increase in pressure.

[@cmartin240]

Excellent research. I knew those damn 40 micron bronze filters would ramp up the back pressure. Great way to blow oil past the seal or worse, the seal itself is damaged.

[@littlefishinggoat5409]

I just purchased a MH provent 200 for my vehicle. I'm glad to see I made the right choice.

[@robh8131]

Really useful comparisons. I'm erring on a system for my UK 2 litre diesel that incorporates relief valves to allow 'through flow / bypass' if a filter becomes clogged. But put off by the silly prices of Genuine Mann 200 Pro Vent CC and the Flash Lube CC replacement filters. Many thanks for your informative test.

[@acaborneo5335]

I was used oct mishimito on my captiva diesel, its make engine seal cover leaks.thanks for make this video very very good

[@802Garage]

That's definitely why! Especially under boost, you crankcase pressures are going to be much too high. Lucky it was only your valve cover seal.

[@802Garage]

Great test. Wow! That eBay catch can could create a lot of problems. That can cause the turbo oil return to be pressurized and back up. That will make the turbo smoke like crazy and can obviously make people think there are all kinds of issues. Not to mention other potential harm from high crankcase pressure. The ProVent 200 setup is impressive as demonstrated many times now. This was all done at idle? Under boost I imagine all of these numbers could change, but the eBay catch can would clearly become the most problematic. Good info to have!

[@moremolecules]

Yes, all was done under idle. I also tried to match the temperature of the engine, i.e. had a quick go around the block to bring the engine to operating temperature if I was fiddling for too long. Yes, the numbers would change under boost, but because there is more suction (turbo spool) the crankcase pressure is the highest at idle.

[@802Garage]

@@moremolecules I guess that would depend on how much blow by there is and perhaps it's different with diesel vs gas, but a lot of gas vehicles see the highest amount of PCV flow under high boost, but not necessarily pressure so I see what you mean. Yeah the turbo will be sucking the most as well, but if you were using a restrictive catch can like that, the flow could be far too much and the pressure would back up causing a massive PCV pressure spike. That's my concern. With a good flowing system yes pressure should be lower. :) Again awesome vid.

[@moremolecules]

@@802Garage Thank you very much indeed, much appreciated. Diesels are a bit different as compared to gas/petrol, they need their turbo, although naturally aspirated exist. Their max crankcase pressure is always at idle. I tested under boost and with any blip of the throttle, you get lowe crankcase pressure.

[@JRgarage1]

Fantastic video. Seriusly congratulation for make this test.

[@BettaharMostafa]

Best Chanel for 1.6 hdi

[@barniboy9336]

Thank you, thank you for a very nice, well documented and scientific approach ! I have also done my part of experiments and come to the same conclusion wrt. the sintered bronze filter. The pressure drop across those is rather high. In your example the filter looked kind of dry. But when this type of filter is wetted by oil droplets over (a short) time, the pressure drop will increase even more. These filters are simply too small in terms of filter area for an application like this, where just a few millibars matter. It is interesting to note, that only the Mann & Hummel filter takes advantage of the cyclone effect, by having a TANGENTIAL inlet. By this, the incoming fumes, with oil-droplets, will be whirling along the insides of the canister, splashing off most of the droplets (being heavier than fumes) at practically no pressure drop. An old trick from the process industry. There is another issue that I have not seen mentioned in the many Oil-Catch-Can videos: The intercooler ! Let me explain: A turbo-charged engine will have an intercooler. This is due to the fact that air is heated when compressed. When air is heated it expands and thus, less air/fuel will go into the engine and nothing is gained from the turbo. Unless you cool the air after the turbo. The intercooler is normally fitted under the radiator and is thus the lowest point in the air-intake system. Where do you think the oil-droplets and oil residues inside the air intake system is gonna end up ? Right ! Over time, must oil films deposited on the insides of tubes and hoses in the intake system is slowly, but steadily seeping down to the intercooler, filling it up. In fact, the intercooler is a perfect oil-catch can, being nice and cool, condensing oil-droplets in passing. Of course, the turbo outlet itself will provide a substantial pressure (thats what they do :-) and so some air is still gobbeling thru, but with limited, or no cooling action. My guess is that most intercoolers dont work. But then again: Its a good thing we never need those 250+ HP just by gurgling around town, so we havent noticed :-/

[@moremolecules]

Thank you very much indeed for the really detailed comment, more than appreciated. I would say it is somewhat scientific, as there are still a few variables unaccounted for, but still better than nothing I guess. Yes, the bronze filter has way too limited surface area. I think Mishimoto realised this as the huge Ford Cummins engine (6.5L) was throwing some errors and they produced a new oil catch can for this engine, much larger surface area and not 50 microns, but rather coarse mesh. Yes, the cyclone effect is pretty good actually. There was a scientific paper on that and it was the most efficient way without increasing/hampering the restriction/flow. I have thought about the intercooler, it is basically an oil catch can in its own right. I have already bought a second hand one to have some tests with it and will post a video someday. I am thinking of a semi-scientific way to test oil catch can efficiency and have some ideas, it is just time that is not enough. All the best.

[@802Garage]

Great insights, but one thing. Intercoolers absolutely work. The difference is massive. I highly recommend looking up the article "How intercooler design can changer the performance, efficiency and power of your engine" on Engine Basics as well as "Drop Intake Temperatures. Drop Track Times. Drop Jaws. The Ultimate Guide for Intercooler Selection!" by Mishimoto. The latter is much less data dense, but still demonstrates what a difference intercoolers make. Intercoolers are also a trade off between restriction, cooling, and efficiency.

[@ahmedalhakimi7251]

Best video of catch can comparison

[@enriquep4857]

Very nice video. Waiting for your "How to replace the trasmission of your Peugeot". I really need this video haha, my car is asking me urgently.

[@moremolecules]

Hahaha, luckily for me it is good for the moment.

[@johnmcmullen456]

Thank you for all your efforts, found it very helpful.

[@etubrutus3501]

Once the filter media gets oil saturated I’m afraid that will restrict airflow causing case pressure to increase.

[@bobreese4807]

Yep, one of the reasons I am leaning to ADD w1 vs UPR.. ADD w1 is on sale for $109 for its V3

[@KingZoneOne]

I have the Provent 200 on my petrol Audi A4, and I LOVE it! It's actually an oil/air separator (not a "catch can"), and it has both a pressure release valve, AND an active pressure regulating valve along with two different types of filter materials (nylon screen and sponge), a plastic coalescence screen, and room for an added wad of steel wool to increase coalescence. The type of filter element is really what matters. I'd never use a "catch can". They are overpriced, are nowhere near as efficient as an actual oil/air separator, and having TWO pressure regulators makes the comparison moot. .

[@stefanogallotta316]

Hi mate. Where did you buy the Provent 200? It is original ? I agree with you catch cans are useless. Thank you

[@RockAndRollFirebird]

perfect work my friend! thank you for this valuable measurement... 👍

[@davidwarren4569]

I don’t think those metal catch cans are meant for diesel engines, just petrol engines. But a nice analysis. Well done

[@moremolecules]

Yes, could well be, although in the description of these they always put diesels as well. Overall there is a bit more crankcase pressure in the diesels as compared to petrols.

[@CrawldaBeast]

I feel like this could be very good information but done in a skewed way. Why would you leave the first catch can in series with the other two? The additional hose length plus the extra can all contribute to restriction. Not to mention, there ended up being a slight kink in the hose going to the last "universal" can. The other thing to consider with the filters is running a new filter (bronze or mesh) will flow far better than one with a thousand miles on it. So technically the second and third cans could be starting to see some filter restrictions caused by the first one starting to saturate.

[@MrAcc45]

I suspected the bronze filter would increase pressure. imagine when it gets clogged up, the pressure would be even more I reckon.

[@moremolecules]

Hi Nizar, yes I was also suprised how much the pressure is with the bronze filter. It really depends on what pressure can the engine reasonable sustain. Overall there will be an increased pressure, but how much this will impact the engine is another question.

[@MrAcc45]

@@moremolecules Thx for the reply. I was worried abt this pressure. My engine has a lot of blowby and the pcv valve would get pretty oily and restrict flow. I keep hvg to clean it with brake clean very often. I have a replica mishimoto with the bronze filter, but this problem u highlighted was a big worry for me. thx for this video, it confirmed my fears. good thing the bronze filter is removable. I plan on removing the bronze filter and just keeping on the round baffle plate. currently im awaiting for some fittings via mail before install. in place of the removed bronze filter, i plan to screw in a barbed connector so that the blowby would have to travel down the can and up through the baffle and finally travel through the barb connector and out the can. hopefully it can capture the oils at the bottom without creating too much pressure. once i have setup I'll do a video and put a link. maybe provide updates occasionally.

[@moremolecules]

@@MrAcc45 That would be really good. Let me know if you do any videos, I'll post it on my community page.

[@phiksit]

Then throw in some cold winter weather and frozen water vapor will clog it up even more.

[@ericsson980]

Very informative. Great video sir. This is exactly what I'm looking for. I'm planning to install Oil Catch Can myself soon but wasn't sure if it's good because some video said not to install it because it will increase the crankcase pressure. Now I know it's the internal design of the Oil Catch Can that effect the crankcase pressure. Got the 'cheap' Oil Catch Can exactly like in your video in our local store. Will get those soon. Thanks again for this video.

[@ericsson980]

Also my car is Mitsubishi triton 2.4 mivec. Has over 100k km on it. Do you think it's too late for installing Oil Catch Can? Thanks.

[@moremolecules]

@@ericsson980 Never too late really. 100k is not that much anyway, so perfect time to put one.

[@ericsson980]

@@moremoleculesthank you sir

[@NZbluesky]

Thank you for displaying your benchmark research. I have just fitted a Provent 200 to a diesel JK wrangler 2.8 Turbo intercooler model 2008 mileage done 200k. The kit from Germany came with quite a few right angled 90 degree connectors. AND THAT is my question. These connections are all internal to the main hoses? So would that push the pressure up? Like a water blaster effect? When I put my figure or white paper over the output of the Provent onto those small right angled connectors there seems to be no pressure at all? What do you think? I thought maybe I would change the position so it just uses the larger [and shorter] rubber pipes as suppled? Any thoughts? Interestingly to myself.... My jeep seems to have picked up power since fitting this Provent?

[@moremolecules]

Yeah, I always thought that many right angles will lead to a little bit of pressure going up, not proably a lot less than one thinks. Restrictions (narrowing of pipes) are are probably the biggest pressure increase, although also not by much. As far as I have learnt, main pressure increase is likely to come where the air/gasses are stopped or are hitting something, like a mesh or even finer filters. It is just a guestimate of course.

[@Refertech101]

Yes you can have some thing that filters good with small delta P, but like any thing, you pay for it, and size is larger, the Parker CCV systems are very efficient

[@gheorghinacov6008]

There is also difference in diameter of hose and connector. Mann-Hummel and your OEM setup got very large hose. Mishimoto and the unknown catch cans had very small diameters compared to the other setups. You can make the test again with the Mishimoto and unknown cans on cars with smaller vent hose diameter. That’s my guess

[@moremolecules]

Yes, I completely agree. It is rather difficult to detemine is the increased crankcase pressure comes from the catch can itself or the smaller hoses. I suspect it is from the hoses. Very good suggestion to testing the same with the smaller hoses for the Mishimoto and the other one. This should show if these increases come purely from the hoses. The problem is that the maximum hose intake is pretty small on the mishimoto. I think I have a smaller-sized port for the mishimoto so I can try it. Thank you!

[@gheorghinacov6008]

@@moremolecules And thank you for your videos! I wait for your next one

[@jasonhumphry5836]

@@moremolecules I'd like to see a hose size comparison as well as I have a dorman oil catch can on a 2012 chevy malibu running small hoses I've thought about changing to large hoses but I also don't want vacuum leaks and it's working perfectly awesome peace and much respect to you 👍 JASON awesome video 😀 👍 👏

[@moremolecules]

@@jasonhumphry5836 Smaller diameter hoses will add a little bit of pressure, but not that much. If you look at the video with the comparison of the cheap universal oil catch can had only little pressure above the mann hummel, despite the hoses being much smaller diameter. So, it will add a little bit of pressure, but not very substantial.

[@jasonhumphry5836]

@@moremolecules thanks for the added information

[@2525miche]

If the Universal Aluminium Engine Oil Catch Can ahave a breather on top, is it still good?

[@moremolecules]

Yeah, it is still good. You can either block the breather or put a filter on it.

[@theseoldhands532]

the oil catch can at 12:00 it isnt backwards that isnt a baffle to stop oil sloshing and being drawn in its a baffle to help oil vaporize and stay in the can and not in the air it sis supposed to be on that side :)

[@moremolecules]

Did not quite get that, sorry.

[@kayakwesty]

Thank you for this video. I will be buying a knock off Provent 200

[@smartbidshop1]

Did you seal the valves on the prevent catch can

[@ViruZHUN]

Recently built a new 2.0hdi engine with the mishimoto knockoff with bronze filter. The oil was coming out of the rtv sealed places, getting rid of that shit.

[@FixItWithJon]

Love your videos. Did you buy a hose & mounting kit for your Provent 200 or did you have to buy separately / make up a kit?

[@moremolecules]

I made my own kit with the hoses and the mounting stuff. Unfortunately, for my car there were not any mounting kits and space was quite tight.

[@glenncivale6824]

Excellent Information, TY.

[@jacovandenheever4318]

To test seperate will be more true test as all that beding and hose lenth will cause extra restrictions. Hope we can se can tests performing appart.

[@moremolecules]

It is a relative test at the end of the day. In addition, the bronze one is compared to another one with the same length hoses, so you get relative restriction compared to each other. The "fake" Mann-hummel does not add anything to the crankcase pressure, so leaving it there does not change the pressure.

[@tracylewisperformance1328]

Why not use an actual air/oil separating crankcase evacuation system that provides full time vacuum on the crankcase? Pressure is never good, and all shown is only using intake manifold for vacuum source.

[@moremolecules]

Hmm, many thanks indeed for the comment, but I am a bit confused. What would that system be? Where would one take the full time vacuum? I suspect of course I can use the car's vacuum, but I simply used the current setup, only extending the path with an oil catch can.

[@Pacobravo16]

The question is a open to atmosphere can reduce pressure???

[@moremolecules]

Yeah, I have not done that, but I doubt it, unless it is not a turbo version. With the turbo version, the pressure gets reduced by pulling the air. So, pretty much when the turbo is spinning the pressure is reduced. With the atmospheric one, there is nothing to pull the pressure out of the crankcase. That is my opinion and can stand corrected of course.

[@Wigwhom86]

How much pressure is too much?? 6 milibar is only 0.87 psi.

[@moremolecules]

I have answered that before and always gets asked. These engines max permissible pressure is 30-35mbar, so you can calculate how much is 6mbar out of that. The original Mann Hummel Provent 200 has a relief valve at the top that opens at 50mbar. So, 6mbar, if you engine is a bit on the worn side of things will get you quite high.

[@GrainGrown]

6 millibars is 0,087 PSI.

[@hulong0205]

I would like to know if oil catch can will create damage to gas engines. 3.8L V6. Do yo have a test for gas engines? Thank you.

[@moremolecules]

Hi there, I really like your question, but very difficult to answer without having your particular engine at hand to do tests. No, I do not have a test with a gas/petrol engine. Nevertheless, the crankcase pressure increase will be the same. The issue is that this is relative. So, if you add a glass of water to another glass of water that is a lot, but if you add that same glass of water to a lake, not that much of an increase. What I want to say is that it depends on how much pressure your 3.8L V6 can sustain or what is normal for that engine. My tiny 1.6L (4 cyls) can only sustain max ~40-50mbars without oil leaking from the seals. Now, pressure in the gas/petrol engine is normally a lot lower than a diesel, so difficult to say without experimentation, unless you know your normal crankcase pressure for you engine.

[@hulong0205]

@@moremolecules thank you for your answer. This answered a lot of my questions. Like pressure difference of diesel vs gas. Appreciate your time and help.

[@moremolecules]

@@hulong0205 No worries, unfortunately I cannot provide more info on that, but that is the general kind of way these things work. Very difficult to get this data (normal crankcase pressure) from the manufacturer, unless one bought the car from new and measured at the very beginning of ownership.

[@nikmohdyazid]

I wonder what's the crankcase pressure if you only use the mishimoto oil catch can

[@moremolecules]

It is the same as running them both. It is just that it was more difficult to do it separately. The Mann-Hummel does not add anything, so what was measured was the actual crankcase pressure.

[@franabad]

Awesome video, wished I found it a couple of weeks earliers! Just installed a Mishimoto on a diesel Mercedes ML270, definitely not comfortable with those values. Nevertheless, the main problem I've been having is that I'm getting oil from the "out" port. Tried it the other way around, the "in" port throught the bronze mesh, and was getting better results, any ideas why? Anyway after watching your video, i think i will remove it completely

[@moremolecules]

Well, not too sure why it is gathering oil on the out port. THe oil catch cans are not 100% efficient for separating the oil, so you will always get some on th eout port.

[@13adrian]

I have been looking at the mishimoto mmbcc-hf that has been mentioned as it hasn't got the brass filter it also has larger inlet and outlet I think 27mm

[@boxpimp]

I’d be interested in seeing what vent to atmosphere pressures look like. I can’t find any info online. It might not apply to your vehicle but plenty of people run breather cans

[@moremolecules]

Hi Jason, I do not quite remember if I did this test, but might do a quick test and compare the crankcase pressure with venting to the atmosphere.

[@mrmotorvator5151]

I run mine to atmosphere using 19mm id hose..seems to work well and can only benefit engine internals..no brainer

[@AndoniFV]

@@moremoleculesllegaste a probar que presión tenías a la atmósfera? Un saludo?

[@moremolecules]

@@AndoniFV Unfortunately I never did venting to the atmosphere test. I did not have at the time a filter that vented to the atmosphere, otherwise I would have tested it.

[@yikesomg3423]

To be honest, these pressures are so small does it even make a difference? except the kkmono/mishimoto one, they all just add like .50 mbar or 0.007 PSI. Is that so bad or negligable?

[@moremolecules]

Depending on the engine, the normal pressure in these 1.6HDi is ~30mbars, so not really that much. Imagine from 1.5 to 6mbars out of the 30mbars is quite a bit. A little bit is not that roblematic, but then it depends on how much the engine is worn already. Say it is not 1.5mbars normal, but already a bit worn and somewhere already at 5mbars, adding another 5mbars is quite a bit.

[@bengleckl1877]

So what is the safest way to hook up a catch can system?? Mine is a gasoline non turbo. Do I need two catch cans or is one good enough??? Just one catch can with no bronze filter would be best??? I assume id want it to be the same pressure it was before I installed anything?

[@moremolecules]

Hi Ben, apologies, I probably made it to look more complicated than it is. Only one catch can is enough, preferably the non-bronze one. If you engine is not too worn (not much blow-by) then even the bronze one will be quite good. If you have an older engine, then I would not recommend the bronze one. Yes, you want the pressure to stay as low as possible. I only used the two, as it was easier and I had them hooked up already.

[@deanharris7149]

Good to know!

[@jasonyoung5960]

I have one of thoes ones with the brass filter. I drilled 4 small holes in the filter and then filled the can with steel wool. I thought it looked restricted. Cheers

[@bobreese4807]

Good idea

[@CONFUCIUS-f2x]

How about making more tiny holes on the disk baffle for more air flow and removing the bronze filter and adding the scrub pad?

[@moremolecules]

Yes, that would work, but then again it will not be too different than the cheap one with the larger holes and the scrub pads. I guess that the bronze filter with a few larger holes will reduce the increase in the crankcase pressure.

[@CONFUCIUS-f2x]

That sounds like a good idea. Weekend project. Thanks Molecule.

[@gregnixon1296]

What kind of hose is necessary for catch can back to intake? The 3/4" heater hose that I used collapses. Heat from the engine makes the hose pliable, and the intake's vacuum pressure causes it to collapse.

[@moremolecules]

Hi Greg, yes the usual hoses that are supplied with catch cans are too weak. I use fuel hose 25mm. It is a bit on the thick side, but it will not collapse, it is too rigid. The other option is to get reinforced silicone hose, but it has to be fuel safe, otherwise it will disintegrate eventually.

[@CarminesRCTipsandTricks]

Teflon lined Fuel Hose is actually the best. More expensive, a little harder to work with - but VERY stable and durable. It's impervious to Chemicals, which is why it's popular to use with E-85 Ethanol Fuel Systems.

[@moremolecules]

@@CarminesRCTipsandTricks Great advice and many thanks indeed. I will have to investigate this to see if I can purchase and replace my own hoses.

[@mohmadJO]

Hello my friend I installed a cheap type oil catch can and it comes with a small filter on top Note that I bought the car three months ago Diesel engine 2500 A month after installation I found a little oil around the manfold casket and inside the intercooler The engine is good, there is no black or white smoke, and there is no oil loss after traveling 3000 km I really don't know if the reason is old or the cause is the oil catch can do it Another question Should the installation be done away from the engine, away from heat? Does it need to be installed a little higher than the engine level? Finally, sorry for my many questions and sorry for my English

[@moremolecules]

Not too sure what the problem is, but ideally you need to place the oil catch can as far away as possible from the heat. At the end of the day the oil catch can is a condensing thing and the bigger temperature differential really helps with condensing oil/water, etc. So, if you can cool the oil catch can really well, say with ice or cold water then the efficacy will be really good. Unfortunately, this is not practical in engines. I would not install an oil catch can higher from the crankcase breather, as the condensing fluid will come back and plug the hole. Ideally you need to put it lower than the crankcase breather so any fuild/oil to go into the oil catch can.

[@mo80ris]

Ths you for sharing bro ✌️

[@kkmingming]

Thank you!

[@don.timeless4993]

thank you so much

[@barry9141]

How would it be different for a petrol engine?

[@moremolecules]

Not very different.

[@MatkoJun]

@moremolecules I'm wondering - could increased pressure for mishimoto/universal catch cans be due to much smaller in/out ports? ProVent has 24mm internal diameter input/output ports whereas mishimoto and other cheap copies are usually around 10-12mm and the biggest I saw were 19mm outer (16mm inner diameter). It would be interesting to see what would be the pressure if one would make ports for mishimoto/universal bigger - say 22mm (which is original hdi hose connector inner diameter)

[@moremolecules]

Most of the increase in pressure does not come from the hoses or the smaller in/ou. I did try the Mishimoto/KKmoon without the bronze filter to see how much this adds. It was relatively substantual increase in pressure, so not just the hoses. But they all add to the increase in pressure. Basically, the bronze filter is the biggest contributer to the pressure increase. At the end of the day it is a balance between complete efficiency and permissive. If you have complete efficiency or close to that, it is to create resistance as the gasses need to pass through something where they have to coalesce, hence the increase in pressure as too big holes and you have little efficiency. Gas molecules, even laden with oil/water are still pretty small molecules.

[@ZanSunstrider]

Nice video but im surprised you didnt test catch can with a breather on top if it :)

[@moremolecules]

Yes, good question. Simple reason I do not have one to test unfortunately.

[@keepitathousand420]

Great test! i was wondering if you can do the reading tests again but after 10-15 minute to be more accurate. Again thanks for the helpful video

[@moremolecules]

I wanted the same condition for all catch cans, so the engine was always in operating temperature. I can wait for the engine to be cold on all catch cans, but I cannot control how cold the engine will be, but I can always keep the engine in operating temperature, so more consistent test across the catch cans. Is that what you meant for the 10-15min wait?

[@keepitathousand420]

@@moremolecules yeah of course it does give more accuracy doing the tests while engine is in operating temperature although you could try test while its cold it won’t hurt to see those numbers before warm up, but what i meant is could you repeat the test after idiling or driving for 10-15 min?

[@moremolecules]

@@keepitathousand420 Yes, the cold ones will be quite big, depends on how cold of course it is outside. Before doing the video I did quite a few runs on this to see what works and is the most representative. Generally, once the engine is relatively hot, the crankcase pressure does not change too much. Say if I drive for a bit and measure then will be almost exactly the same as if I had stopped for 10min to change the catch cans. I can probably do it anyway and see what comes out.

[@moremolecules]

@@keepitathousand420 I probably could, it would not hurt, but the difference is very little between these.

[@ABDULLAH.84]

So the bronze filter is no good, right?

[@moremolecules]

I would not say it is no good, but it definitely adds a bit of crankcase pressure. If your engine is not really worn out, it should be ok.

[@robpaul7900]

Wish I realized this earlier before I had left a catch can on my truck for so long. Don't ever buy one of those brass filter mishimoto cans you can get an identical one for 20 bucks on Amazon different company replica, can't believe mishimoto charges like 200 for thiers what a rip off.

[@xabizar]

Great work! Is it possible that the actual mishimoto catch can's bronze filter is less restrictive than the cheap copy's filter?

[@moremolecules]

It is possible, but unlikely. I linked a video (in the description of the video)) of a comparison of the original mishimoto and the "fake" one and they are identical. I suspect it might be just the same factory producing them, but does not label them mishimoto

[@GCS88]

I've read in a forum before that its pretty restrictive, Mishimoto has then redesigned and replaced the bronze filter with some kind of big pore sponge type filter that covers the whole ceiling area of the can.

[@smailberrani2914]

Malheureusement je ne comprends pas très bien l'anglais, mais vraiment ça me semble exactement c'est qu'il faut pour ma 308 1.6 hdi, je ne sait s'il existe un version française, ce serait idéale et intéressant pour beaucoup de monde.

[@moremolecules]

Hi smail, merci beaucoup. I do not speak French, but there is auto translate in youtube. That in theory should work ok.

[@kumara5492]

Well detailed video. I followed your video and installed OCC successfully. I ran my Toyota Prius hybrid on maintenance mode for almost an hour ( to check if it's still overheating intermittently due to weak water pump that I replaced with new water pump and that's been fixed ) but I noticed the hose that I connected from outlet of Oil catch can ( universal OCC) that goes into the intake manifold was completely flat due to high pressure. Do you think OCC might not be functioning as it supposed to or should I replace the hose with the heavy duty hose ( thicker one) , like the one I got that connects from PCV valve to inlet of OCC. Do you think I need to get a fuel line hose which is thicker than the one I installed ( maybe I got radiator hose ) .I subscribed. Thank you for you reply

[@moremolecules]

Yes, replace the hoses with heavy duty ones that would not collapse under pressure/vacuum. I would get something that is fuel safe hose, but such that it would not collapse under pressure.

[@dinnicusor5312]

AM O INTREBARE ,AVAND IN VEDERE CA TURBINA FACE UN ANUMIT VID DE PRESIUNE IAR SUPAPA PCV INCHIDE SI DESCHIDE LA ANUMITE PRESIUNI IAR CEI 6 MILIBARI PARE O PRESIUNE MICA SI CE PRESIUNE MAXIMA ADMISA TREBUIE IN CARTERUL MOTORULUI ? SI MULT SUCCES IN CONTINUARE

[@moremolecules]

Yes, 6mbar seems like low and that is on idle bear in mind. The maximum on a brand new engine is ~30-35mbar, so 6mbar is quite substantial if one thinks about it. Unfortunately, I do not have the specs, I took the 30-35mbar from a different similar engine, but it is in that ballpark figure.

[@AtalixZero]

Is it truly fair to keep calling a knock-off copy a "Mishimoto" can? Can we really assume the replica is of the same build quality and material quality?

[@moremolecules]

Well, one can never be sure the quality is the same, but I am nearly certain that it is of the same quality. I can bet a few $£ or whatever currency that these come from the same factory that built the original mishimoto

[@DominicLeung87]

Sorry if I'm being stupid but your pressure numbers are "delta to atmosphere" right? 6mbar is 4 times 1.5mbar sure... but we're taking about less than 0.1psi, surely that can't really make a difference for the sesls in the engine...

[@moremolecules]

Hi Dominic, yes it does not need much pressure to do damage to the seals. I know it is tiny pressure, but the maximum for these engines and a few others is ~35mbars. The original Mann-Hummel Provent 200 has a pressure relief valve on top that opens at 50mbars, so this is really the maximum that they think is quite high.

[@DominicLeung87]

@@moremolecules that's quite interesting I haven't really heard of this being an issue before but it does make sense upon thinking about it further Thanks for the hard work putting all this to the test!! If you don't mind discussing a bit further though, do you think the situation /issue you described is the same for turbo- gasoline engines? I just ordered this unit from mishimoto(www.mishimoto.com/mishimoto-baffled-oil-catch-can.html) that has a removable bronze filter which seems to have bigger surface area (which should reduce pressure drop), what do you think of the design? Should I run the catch can with the filter removed? At the end of the day the catch can add a device is facing an engineering challenge with two conflicting conditions. Like any filter it needs to flow well, and to filter well. Certainly there can be "bad" designs which do both poorly or performs very well in one area at great expense to the other. What design elements do you think are indicative of a system which can do both things well? To me it would be : Size - a large can would allow the crankcase gasses to slow down (atleast a bit) making it easier for the oil droplets to come out of suspension Flow characteristics - designing the can in such a way that the crankcase air "fully utilizes" the space in the can so it can achieve the effect described above Filtration - something to "actively" encourage separation between air and oil vapor, you're could be a fibrous element, or bronze "sponge" or centrifugal vortex (like Dyson vacuum). Obviously it is case dependent but which area should we prioritize, the filtration or impediment to flow?

[@moremolecules]

@@DominicLeung87 Thank you very much indeed for the really thorough and good comment. I absolutely agree that it is a trade-off between efficiency and flow (increase in pressure). There os very little amount of actual academic research on this subject. I think I found one single paper that talks about the components in an oil catch can. The paper mainly looked into how the air needs to swirl around in order to maximise the amount of time the droplets/air are in contact with the oil catch can surface in order for them to coalesce. The research showed that circular motion of the air is the most efficient, that is the same design as the Mann-Hummel. Unfortunately, they did not go further into this. The problem is that how much is too much pressure. There are too many factors to account for here. How old/worn is the engine will determine the amount of breathing the engine does, the more worn it is the heavier the breathing and the same amount of restriction (oil catch can mesh) will give you different crankcase pressure. For some engines this will result in leakage from the seal, others would not. As far as I am aware almost all catch cans are the same design with variations here and there. Nevertheless, mishimoto noticed that in diesel engines, albeit the really big 6.7L ford cummins, their oil catch cans creates too much crankcase pressure. So, they designed a new more permissive oil catch can. When I say permissive, I mean bigger surface area, as you mentioned in your comment. www.mishimoto.co.uk/ford-67-powerstroke-catch-can-install-2017.html If that oil catch can was available for a reasonable price, I would definitely buy it, IMHO seems like a very good compromise of everything. The overall problem is how much crankcase pressure is OK for the engine. Very difficult to answer and very little information anywhere. I managed to find only one single source for a mini petrol engine and the maximum there was ~20-30mbar, which is not that much actually. I could go on about this forever, but my reply would turn into a blog post :-). Hope that is somewhat helpful.

[@DominicLeung87]

@@moremolecules awesome man Yea there really isn’t much research on the topic other than those done by the amateur grease monkey I’ve been scouring the internet the past 24h after I saw your video My catch can just arrived in the mail today and I’ll probably just install it. I’ve got a bmw 2.0 turbo which shares the same pcv hose diameter as bmw’s 3.0l turbos used in the M2 M3 and M4. Given blow by is largely a function of engine airflow (i.e power), I figure that even if the Mishimoto catch can I bought comes with some restriction, atleast I have a lot of headroom given the stock tubing is massively overbuilt. Super finger in the air approach 😀

[@moremolecules]

@@DominicLeung87 Good luck with the catch can. It should be OK. I have an idea of how to test different oil catch cans, but I will see if I can do it. Most of the grease monkeys just say, "ohh, this oil catch can is the best", etc. There is no comparison whatsoever, as long as there is something collected in the oil catch can. The problem of course is to emulate the size of the droplets, as the function of the oil catch can will depend on the size of the droplets. No easy way for me to test their size, apart from a sophisticated scientific equipment.

[@dieseltips]

Excellent work my friend. When you take out the oil filler cap do you see smoke and pressure coming out?

[@moremolecules]

Hi DieselTips, there is not much smoke and pressure coming out, of course there is some.

[@ptownhoopsquad]

Hey, great channel, loads of very good info. Just wondering if you have replaced the plastic inlet manifold? I just got a 1.6 hdi 145k miles. The inlet is really blocket up with carbon and goop. I dont think i will be able to clean it out of the plastic inlet. So i want to buy a new one. I am looking on ebay and all are aftermarket, just wondering if they are any good quality

[@moremolecules]

Thanks for the encouragement. Which plastic inlet manifold is that? Is it the PCV valve one?

[@russ4972]

On the universal catch can where do you put the mesh? In the main body or screw off the little baffle and stuff it in there?

[@moremolecules]

Hi Russell, I would put it in both. I would certainly put some in the little baffle, but in the main body will increase the crankcase pressure, although only slightly. In the main body will give a chance for the oil vapour to hit something and potentially coalesce into larger droplets and eventually into a liquid.

[@xl250mon5]

Atmospheric pressure is 1013 millibars (14.7 psi) your readings of 1.5 millibars indicates a crankcase pressure of .02 psi therfore a vacuum .

[@moremolecules]

Hmm. It is DPF sensor with two inputs, one for atmospheric pressure and one for whatever you want to measure. So it is relative pressure, i.e. relative to the atmosphere, 1.5mbars is 1.5mbars above whatever the atmosphere was at the time. Atmospheric pressure is also not constant. If it is raining the bars might have dropped already to 950 say.

[@olafbrescia8389]

Do you still use the extra steel wool in the ProVent 200 with excellent 1.58 and 1.54 mbar readings? My current setup leaves no residue in the intake pipe or throttle body (great!), but my suspicion is it's causing too much back pressure over time. My valve cover has begun leaking. Does the ProVent w/mesh screen filter - clean the air well ???? I'm not going to return oil to the sump, but I would like the outlet air on the ProVent to be very clean, however. Suggestions?

[@moremolecules]

I still use it yes, but it might create back pressure or crankcase pressure. If that is the case, I would remove them altogether. I would not return to the sump, it is just that the filtered oil is not that clean, although onece the engine is in operating temperature all the stuff gets evaporated anyway. With the original paper filter it should clean well. Only way to see it is to have a go and see if your intake gets a bit oily. If it does, then have the mesh not too dense at all and add a bit more with time and monitor. All of these depend on how much crankcase pressure there is in your engine already, so difficult to tell and only experimentation will help you.

[@olafbrescia8389]

@@moremolecules My rather sudden valve cover oil leakage is suspicious. I've been using a Moroso Oil Breather Tank with a positive breather attached w/return vacuum - but started driving the car a lot. I just ordered a copycat ProVent 200. I removed my wiper-wash tank on the other side of the engine bay and have long hoses to the Moroso - so this is cold and works very well. In your application, I would put straight copper pipe where possible to assist in condensation collection or move the tank far away - so it is cold. The Moroso inlet is simply too small - to ProVent is better. My application is modified VR6 12v 6-cyl. Great videos man!!!

[@Prairie_Barbarian]

Thanks for this video. I installed one almost identical to the generic catch can on my old carbed Harley. Beings it is on a motorcycle, the can is being sloshed back and forth constantly. I can say without a doubt, the baffle system on the generic can works perfectly. Collects all the blow-by very well. I've also tested the outlet hose to make sure (I run mine to atmosphere) by taping paper towels to the end to see what it would collect and it was bone dry, as intended. Here it is when I first installed it, the description has more details kzbin.info/www/bejne/fYjKnHxtiMutlac

[@moremolecules]

I yes I see. Looks quite good to me. Many thanks for confirming that the baffle system works, I always wondered how well this does.

[@Prairie_Barbarian]

@@moremolecules My train of thought with the brass filter is it's pretty much pointless. By the time the blow-by reaches the canister, the lower temp difference of the can should be enough to make the vapor coalesce. Kinda like the oil separators of old, none of them used a filter and they all relied on baffles. Like I said in my prior comment, my baffled catch can is being sloshed in ever which direction, plus it's on a Harley so it shakes to beat hell, constantly. Never spilled a drop. The generic one works GREAT. The brass filtered one is over engineered and restrictive, you gotta let that engine breathe!

[@moremolecules]

@@Prairie_Barbarian I completely agree with the bronze filter. It is too restrictive and increases crankcase pressure. Probably filters a bit more, but the increased pressure will not do the engine any good.

[@Refertech101]

@@Prairie_Barbarian they are meant for closed systems where the intake vacuum compensates for the added restriction, the job is to reduce gas velocity to allow vapours to settle out . this is why they are called CCV filters (Closed crank case ventilator) More and more places it is becoming illegal to dump to atmosphere and here in Canada in certain provinces they WILL fine you if caught. and they do DOT road blocks often and random. All so he is using a bottom of the barrel units, If he got the higher quality units they have very effective recovery rates with much lower delta P, The Hummel with the better cartridge works pretty good with minimal Delta P.

[@tedeganagondi]

Please make an video with original pv 200 filter element while clogged with oil👏👏

[@moremolecules]

Ahh, you mean used filter with the same measurements. Hmm, I might do that, seems like a good test as it can actually increase the pressure. I did not think abou that, thank you for the suggestion.

[@tedeganagondi]

@@moremolecules exactly👍🏻After 10k use or more.

[@moremolecules]

@@tedeganagondi Yes, good suggestion. I may try and see what happens.

[@tedeganagondi]

@@moremolecules thats a big debate in forums right now.i guess It will draw a big attention because nobody has done such a test till now🤗Keep up the goow work👍🏻I really like your content.

[@s0007]

Will this also increase pressure for a petrol engine? I see a lot of ppl running catch cans for a boosted (SC or turbo) petrol engine and maybe its doing more harm then good by increasing Crankcase pressure

[@moremolecules]

Yes, there is no principal difference in the crankcase pressure increase in the petrol engines. It is just that diesel engine have much higher combustion pressure of the gasses as there is no spark. What I am trying to say is that as far as I am aware, with some oil catch cans, e.g. the bronze filter ones, there will be some increase in crankcase pressure. The problem is to estimate how much is too much.

[@Alfafanatico]

You are trying to say that 6.20mbar which is only 0.01bar is dangerous?

[@moremolecules]

Yes I do. Depending on the engine of course, maximum is ~30mbar before you get oil leaking from various seals. I can find the reference that I manage to find online and it was only with respect to 1.6 petrol mini, but you get the point.

[@Alfafanatico]

@@moremolecules Your car original PCV/CCV hose inner diameter is 23-25mm? Mishimoto/KKmoon oil catch can inlet and outlet diameter is about 10-12mm. It's no surprise that pressure will increase after that. But yes, that bronze filter is not a good stuff in there. Too much unnecessary restriction.

[@moremolecules]

@@Alfafanatico I did try the Mishimoto/KKmoon without the bronze filter to see how much this adds. It was relatively substantual increase in pressure, so not just the hoses. But they all add to the increase in pressure. Not too sure, but the mishimoto/kkmoon are I think

[@Mark_182]

Hi!! excellent video! cool!!! So would the kkmoon's copper filter be a good system for gasoline engines? Or would you recommend the Provent for a gasoline engine?

[@moremolecules]

If you can afford it I would still use the Provent, although the kkmoon is also alright. The only negative of the provent is that you need to replace the filter every so often, probably something like 20k miles.

[@Mark_182]

@@moremolecules ok!! Actually, the issue of changing the filter doesn't bother me, if it helps the engine, it's fine for me, thanks for the help!!! 🤘

[@moremolecules]

@@Mark_182 I am always penny watching, so that is why I mentioned it. If you have not probelm with cnahging every so often it is a good system.

[@Mark_182]

@@moremolecules excellent thank you very much!!! 😃

[@YouTube--Video]

Danke super erklärt habe 👍 vielleicht habt ihr auch auf meine Frage eine Antwort??? es geht um den zwei Liter TDI..Macht es da Sinn eine Öl catch can zu montieren? Bitte um eine detaillierte Antwort. Danke schön

[@moremolecules]

It is worth it. At the end of the day, these direct injection diesel engines are designed the same way. You get some oily vapour coming from the breather/PCV/CCV valves to the turbo and air intake, which combines into pretty hard stuff with the carbon from the EGR valve. You also get some carbon deposits on the back on the intake valves. An oil catch catch should minimise the oil, so you only get carbon from the EGR. All in all is worth it. WHat is the efficiency is difficult to tell, do you get 15% of the oil in the oil catch can or say 80%? I do not know, difficult to tell. Probably somewhere ~20-30%, maybe less. So, does it make a difference, also difficult to tell, but probably it does. I saw that some people have fitted the 1.9TDI with oil catch cans, so I suspect the 2.0TDI is probably not too difficult to put an oil catch can to it. If you want to keep you car for longer, probably worth it, if not, then probably not worth it.

[@BrainDeadEngineering]

HUGE!

[@kiko2934]

If pipes of the second catch can are with the same size as Man's catch can ( about 20mm), then I think everything will be okay

[@moremolecules]

Unfortunately, the pipes for the other oil catch cans are ~9mm, so much smaller than the 20mm Mann Hummel. That is how they were designed, smaller inlet/outlets

[@kiko2934]

@@moremolecules I think that is another reason for more pressure in the crankase. They can be larger, but not smaller than the size of car's hose

[@moremolecules]

@@kiko2934 Yes, I completely agree, the smaller diameter pipes will add to the crankcase pressure. It is a restriction.

[@Lebanese_housos1983]

It would be good to compare a cheap catch can with a breather on top for pressure value

[@moremolecules]

Yes, that would probably be interesting, although I am not entirely sure about it. Say if you are running the car in gear down a hill, the pressure in the crankcase will be negative, but if the breather on top will negate this.

[@Lebanese_housos1983]

more molecules found out that breather are illegal in Australia 🇦🇺 not allow to let fume oil out into atmosphere

[@moremolecules]

@@Lebanese_housos1983 Due to emissions that might be illegal in most conutries. The oil catch can system is a close one, so nothing is vented in the atmosphere. Most likely reduces the emissions, as it reduces the amount of oil burned.

[@davechristensen5217]

what did he say ?????

[@moremolecules]

I already said it in the video 🙂

[@derverdachtige1406]

do you guys think, i can use the KKmoon for my mazda 2.2 turbo diesel?

[@moremolecules]

It really depends on how heavy breather is youe mazda 2.2. If it is not a very heavy breather, i.e. not very worn engine, then it should be OK. If it is then I would use some of the more permissive ones, e.g. mann hummel or the universal one.

[@Hellogoodbye_]

What if you have excessive blow by and oil build up in intake manifold

[@Hellogoodbye_]

Which one would you recommend for that?

[@moremolecules]

@@Hellogoodbye_ Depends on how excessive is the blow-by, but still any of them would be alright. If you are worried about gaskets, etc., the Mann-Hummel would be better.

[@Hellogoodbye_]

When I remove my oil cap my oil sprinkles out and I feel air and suction. Also do you recommend the oil can with bronze catcher. A lot of people say it builds more pressure it that true.

[@moremolecules]

@@Hellogoodbye_ Yes, the bronze one will build up a bit more pressure, but it really depends on how much the blow-by is. It shoud not increase the pressure by a huge amount. When you remove the oil cap, there will be some oil coming out from the spinning camshaft and of course some air from the blow-by. This is normal, but excessive is not normal. Now defining excessive is a bit difficult and it depends on the engine. I would not recommend it, but there have been numerous people that do not have a problem with it.

[@mrmotorvator5151]

Thankyou..wonder what results an inline filter would make

[@moremolecules]

Good question, although do not have access to one to test.

[@mrmotorvator5151]

I have a cheapo one,inline before catch can and then outlet to atmosphere with blank at turbo inlet...my question,does the engine suffer any negatives at all from no recirculation of these gasses..thankyou

[@moremolecules]

@@mrmotorvator5151 Not really, but it depends on the engine ECU. In the olden days, everything was vented in the atmosphere, Check any old photographs of a highway, you will see the oily streak in the middle of the road. They used to have a slightly cut outlet to create low pressure for the gasses to escape. The modern engine's ECU has built in calculations how much of these gasses go through so it accounts for these. If it is a turbo engine, but even non-turbo one, then the suction from the turbo helps suck these gasses and lower the crankcase pressure, so it is beneficial. If you leave it to vent in the atmosphere you would only rely on the crankcase pressure to push it out. Long-term it should not be detrimental, it just that the crankcase will always be under positive pressure, as there will be no suction, just pushing the gasses out.

[@mrmotorvator5151]

@@moremolecules I found a noticeable increase in pressure especially at idle..I think vacum is needed to draw pressure at low revs..I have reverted to stock piping with inline catch tank..seems to work best on my gm 2.0

[@moremolecules]

@@mrmotorvator5151 Yes, without the vacuum you just rely on the positive pressure from the crankcase gasses to purge themselves out.

[@petermorton2869]

This oil catch can you are using is not the correct one & you need one that has an external filter on it otherwise you will get too much pressure build up which no good at all Kind Regards Peter

[@moremolecules]

Which one of the 3 you mean. It does not need an external filter. At the end of the day it is just an extension for the air intake. If it is not there the pressure is the same. In other words, it should not lead to much increase in pressure.

[@marcodimaio3087]

Why on petrol engine it’s going to be fine that higher pressure and with Diesel engine it isn’t

[@moremolecules]

Hi Marco, I probably did not quite express it correctly. The pressure in petrol engine will also be quite bad, gaskets leaking, etc. AFAIK, there is a lot more negative pressure inside petrol engines as compared to diesel engines. Then again, I have not really worked on petrol engines.

[@michaelvanna8982]

Hi. The last small catch can you mentioned, it is acceptable to insert a little mesh on the exit/out? Currently my setup is same catchcan but i drop a bigger mesh at the bottom of the can ( around 1/3 in height). Is removing the bottom/base bigger mesh and inserting small mesh on the exit upper side instead be a bit better to relieve pressure and trap oil? Tnx so much

[@moremolecules]

If it is the same as the one I was showing then it is acceptable to put a mesh on the in/out. The small mesh does not add too much to the overall crankcase pressure. In the bottom is also ok to put a mesh/steel scourers . Probably putting both meshes inside is OK. Overall it is much less than with the bronze filter.

[@michaelvanna8982]

@@moremolecules thank you. Many OCC users may not be aware about crankcase pressures. Your info serves as a great guidance👍😷🙂🍁

[@michaelvanna8982]

@@moremolecules question: how about instead of a mesh at the bottom, can i just use a baffle plate and a small upper exit mesh setup?

[@moremolecules]

@@michaelvanna8982 Yes that is alright, although the baffle add a little bit of pressure, but overall is not that much. The crankcase pressure in all of these will not change that much, but what matters is the efficiency of the oil catch can. I do not have much of an answer to that, although I am thinking of a way to test this.

[@michaelvanna8982]

@@moremolecules hi. Update: so i decided yesterday to uninstall the last OCC (we have the same) you showed in the video. Instead, i did the opposite by using the Kmoon/mishimoto like OCC. The main reason is i want to use the drain valve. So i modified the OCC by removing the main restriction, all baffles. So basically i left the can empty inside. I run 100kms yesterday and will run again later today. Then will try to drain if any later. So far yesterday, i did not experience any engine chk lite, nice steady idle, my vacuum reading is -10psi at idle....more updatea to come

[@mahmutyaldz4944]

Hello, are the inlet and outlet directions of the universal oil catch tank reverse? So, are we going to connect the input to the place where it says output, and the output to where it says input?

[@moremolecules]

Yes, as there were labelled wrongly. I was basically following the mishimoto setup, which is the correct one.

[@mahmutyaldz4944]

Thanks 😊

[@aragrox]

Ur paypal not working, cant send nothin

[@moremolecules]

Yeah, sorry about that, I rarely get sent anything, so I have missed paypal's prompts to update merchants info. Many thanks indeed for the reminder to do it. Shoud be up working in the next few days in case you have the desire to send something. Much appreciated.

[@papaxlimitzouras]

hi friend, i have a 1.4hdi peugeot, which is the better of the three you testing for my engine? thanks in advance.

[@moremolecules]

Good question, but unfortunately I do not have the answer. Here is my thinking. No matter what the engine the oil catch can is a device on its own, it just filters the oil that will end up in your engine. Which is better, no one knows, or at least I do not know. Without a more comprehensive comparison, i.e. efficiency testing it is really difficult to say. If you can afford it, I would still go for a genuine Mann-Hummel Provent 200. If not, then the cheaper version should still be alright. I would even just purchase the paper filter and put it in the cheaper body. I have a video on that. I would not buy the bronze filter oil catch can, it creates too much pressure in the crankcase.

[@papaxlimitzouras]

@@moremolecules i just buy 2 of that from Alli.... I do a best choice? One for my Peugeot 1007 hdi 1.4 and one for my Renault Clio mk2 dci 1.5 K9K. I appreciate for your answer.

[@moremolecules]

@@papaxlimitzouras Yes, two of the cheap Provent 200 would be alright, as long as you can find a space where to put them in the car. Also, make sure that the hose from the crankcase breather is lower than the oil catch can.

[@papaxlimitzouras]

Friend i want to ask you about the pcv valve. If i installation the oil catch can, i need the pcv valve or i remove it?

[@moremolecules]

@@papaxlimitzouras Yes, you still need it. The PCV valve tries to condense oil and put it back in the engine, I mean perfectly good oil. If you remove it, you will have too much oil in the oil catch can.

[@LoFiOAS1S]

you dont need two you need one m8.

[@moremolecules]

Are your sure though? What do you think the efficiency of an oil catch can is? Have a look at this video: kzbin.info/www/bejne/l4DKq2iaqt12jMk Best case scenario an oil catch can is efficient ~50%, although this is a guestimate.

[@LoFiOAS1S]

@@moremolecules empty oil catc can like that other one does do about 25-30 percent also intake line to oil catch can must be in lower position than the outlet line, that way the pressure will be less, and yes you need only one.

[@LoFiOAS1S]

Oil catch can with both lines in same height is not effective beacouse of the turbulance in side the catch can. Also biger the engine bigger the oil catch can. To be an efective catch can it must be loaded with aome kind of filters a kind of like regular oil filter, intake hose must be on a lower position than outlet line and you are good enough, you dont need other one at all.

[@moremolecules]

@@LoFiOAS1S I agree with some of your points, although I have not seen a single evidence of those. The only scientific manuscript looking at this was comparing the stream of gasses entering and concluded that the swirling action of catch cans like the Mann-Hummel are more efficient than straight in. That was due to maximising the contact surface of the droplets. Noone has ever looked at actual efficiency. Mann-Hummel for example have the inlet at top and outlet at bottom, but I would agree that it should be more efficient to be the other way round, although this increases the risk of blockage.

[@moremolecules]

@@LoFiOAS1S I have not seen a single evidence (proper evidence such as a scientific manuscript) looking at the efficiency of oil catch cans. Most of this is hearsay and blogs/youtube of the like: "this one is better than this one" or "it works, look how much it has collected". In order for one to say 25-30% for that one and 60-70% for another you need controlled conditions (e.g. temperature of gasses, speed of the flow, volume of the flow, size and density of droplets).

[@nikolaynikolov2385]

👌👍👍

[@jplunkett3647]

Second Comment = I have been performing Due Diligence ( Crankcase Ventilation System ) FOR Ford 2006 Powerstroke 6.0 L Diesel F250 Auto Trans 4x4 To date Narrowed Down to Following - Parker / Racor - Provent - Ryco = Seeking THOUGHTS on any of above THREE OR do you have another OPTION I should consider Installing ? Many thanks to ALL Who may view this Comment in advance

[@moremolecules]

Hi John, your engine is pretty large, but I may have to come back to you on the options listed. The Provent 200 or perhaps 400 would be quite good. In addition though, maybe the mishimoto high flow would also work fairly well. With the 6.0L diesel you do not want something that would restrict too much and lead to crankcase pressure build up.

[@kevinoneill41]

I like the double catch can system. But that is just a play on emotions. After say 5000km how much oil. I will call it engine sewage that I do not want in my combustion chamber not ever. How much was collected in the cans. Did adding the second can help?

[@moremolecules]

Yeah, it was only an experiment, I did not run it with two oil catch cans for long. Nevertheless, how much oil is rather difficult to answer. I had quite a few videos about how much it collects. In all honesty it depends on how worn the engine is of course. Most surprising was that the oil catch can pretty much most of the time collects water. Mixed with oil it becomes a bit milky substance. Depends on the weather of course, here in the UK it is more often than not humid or raining, so I collected a lot of water, but say California or here in the summer it collects mainly oil. Not too much to be honest, but that depends on the engine.

[@CensorshipGenesis]

Worth mention, never forget the "golden rule". Before doing ANY engine modification. Make sure the engine is performing to the best of it's own abilities. Meaning in this case. Make sure to PCV is working perfectly. And oil changes are up. All in all excelent video. Cheers

[@ozstriker4075]

Excellent video with great testing methods. So I've got the numbers right, the actual pressure with the mishomoto + bronze filter was 4.62mbar? (6.20 - 1.58 as it was connected with the man Hummel)

[@moremolecules]

Almost correct. The Mann Hummel 1.58 was 0.01 or so different from the natural crankcase pressure of the engine. So, leaving it there does not add more crankcase pressure, thus no need to do 6.20-1.58, it is 6.20. Hope that makes sense.