catch can.

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I had a turbo diesel car which made intake gunk very quickly. It was supposed to be the meeting between PCV flow and cooled EGR gasses. Cleaned it out. Installed an oil catch can. From there, only thin dry black soot coating was building in the intake.

For me this is a practical use of oil catch can. Where there's no issue, I don't think about it.
 
sorry guys, forgot about auto correct, 2016 Ram 1500 5.7 hemi 2000 miles on it.
 
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Oil cathc cans are a fantastic idea! I have one on my pickup and love it. When i had taken my intake off to replace the knock sensors the manifold had an unsettling amount of oil trapped in it. My catch always has about 200-300ml in it when i change the oil every 10,000kms.
 
Anyone who says a catch can does not do anything has never used one, or does not know that they have.

The amount of OEM applications of catch cans has multiplied over the past 10 years. The OEM is not always the sharpest tool in the shed, but the fact so many are jumping on board definitely says something.

In using catch cans, I have collected a fair amount of oil that would have otherwise coated my intake, or been burned in the engine.

It's not a life and death issue most of the time, but there is definitely room for improvement.
 
I built my own catch cans for the vehicles below and drain it at every OCI.

This is what I drained out of the Subaru catch can last month after 5K miles. An almost half full eight ounce bottle that has between three to four ounces.

20170113_223712.jpg
 
Originally Posted By: 6starprez
I built my own catch cans for the vehicles below and drain it at every OCI.

This is what I drained out of the Subaru catch can last month after 5K miles. An almost half full eight ounce bottle that has between three to four ounces.

20170113_223712.jpg



Did you ever take pics or put together a parts list of what's needed to build one? I'd be interested in checking it out, I'm pretty sure a few other members would as well...
 
Many years ago there was a company (I think it was something like Oildex) that made a catch-can PCV combination that you could adjust. The PCV was a real fine piece of work. We experimented with it on a flow bench and tried several setting before picking one. I can not remember what the setting was but the whole setup worked great. I had one on my then new 70 Ford Econoline with a 302 V8. For what I washed out of that jar I'd say I would rather not have that gunk dumped into the intake manifold.
 
The catch cans I've seen have been on turbo Diesel pickup trucks. The factory vents the crankcase direcly into the turbo inlet, resulting in oil collecting in the duct at the turbo compressor inlet. With newer higher efficiency turbos the air gets hot enough to cook the oil, leaving a mess of carbon in the system.

The problem with all of the catch can systems I've seen is that they vent to atmosphere, which is not OK in many jurisdictions and Diesel crankcase fumes can at times compete with a CS grenade as a nose and lung irritant. I don't know if they are venting to atmosphere due to space limitations or if there is some other gas flow reason that makes the cans ore effective when vented to atmosphere. I would think that the compressor inlet would be a good place to return the "filtered" crankcase vapors to and I'm guessing that lack of space for the extra plumbing is why they don't.

Are you guys hooking up catch cans that remain part of a sealed system? That would be a very good solution.
 
Originally Posted By: demarpaint
Originally Posted By: 6starprez
I built my own catch cans for the vehicles below and drain it at every OCI.

This is what I drained out of the Subaru catch can last month after 5K miles. An almost half full eight ounce bottle that has between three to four ounces.

20170113_223712.jpg



Did you ever take pics or put together a parts list of what's needed to build one? I'd be interested in checking it out, I'm pretty sure a few other members would as well...


I did last year. It's in the thread below....

https://bobistheoilguy.com/forums/ubbthr......#Post4000971
 
I installed a catch can on my 2011 Kia Optima with the 2.4 l GDI engine. I change my oil every 10000 km but drain the can every 5000 km. I get the most gunk in the winter months ( at least 500 ml/10000 km) but still get at least 100 ml during the warmer months.
 
Originally Posted By: DoubleWasp
Anyone who says a catch can does not do anything has never used one, or does not know that they have.

The amount of OEM applications of catch cans has multiplied over the past 10 years. The OEM is not always the sharpest tool in the shed, but the fact so many are jumping on board definitely says something.

In using catch cans, I have collected a fair amount of oil that would have otherwise coated my intake, or been burned in the engine.

It's not a life and death issue most of the time, but there is definitely room for improvement.


Or actually they use common sense and know that 99% of say 250k mile or 500k mile vehicles didn't have one and made out perfectly fine. Just because you see something happening doesn't mean it's doing anything that matters lol

Think about it like this. I can put a can that leeches some fuel from going to your engine and make the claim "it's collecting bad fuel that had contaminants!", but it's not actually doing anything. Same idea with catch cans.
 
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If your vehicle has an oil/vapor separator of adequate size, vertical height, and a decent amount of baffling inside it will perform the same function as a catch can. I am inclined to think that vehicles that don't do a good job of "purifying" the crankcase blowby vapors might benefit from use of a catch can. I'm not too concerned about my Mazda Skyactiv. The high compression leads me to believe that there should be less blowby in the first place and Mazda includes a rather large separator assembly under the intake manifold. There have been posts about Mazda's strategy of quick heating of the intake valves and higher valve temperature to combat deposits. I tend to thin that, since their engineers were fully aware of the concerns, that they would have designed a PCV system to minimize oil in the intake tract.

I'm just speculating out loud here.
 
I have two catch cans on my Hyundai 2L turbo. The PCV side catches a lot more than the turbo side. The turbo side is almost pure oil whereas the PCV side is condensed water and gas blowby. The PCV side is sealed, the turbo side is open to the atmosphere though the air filter.

Every oil change (5k miles) I empty them. I've found the more humid it is the more you collect on the PCV side. It is also beneficial to have the can in a cool place as it helps with the condensation of the PCV vapors.

The top layer is oil from the turbo side, the rest is the PCV gunk. And the PCV gunk will evaporate away to almost nothing if left open or dumped on a solid surface.

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I wonder also if that oil vapor/tiny oil droplets getting into the intake tract might to some small extent be acting as an upper cylinder lubricant.
 
Be sure to mount the can as far from the engine as possible, in front of the radiator is ideal. You want the can as cold as possible to help the hot stuff condense and stay in the can, rather than remaining as a vapour and going all the way through the system.
Also, effective baffling and wire wool provide/Brillo pads etc provide more surface area on which matter can coalesce.

The problem with catch cans is that, even with 100% effective separation, you are still sending incombustible gas back into the cylinder and reducing the effective displacement of your engine. Also, that blowby is still warmer than ambient and can contribute to preignition. Oil vapour also promotes preignition.

For best engine cleanliness and best power and best economy, and either map out or blank off the EGR and do not direct PCV vapour to the inlet manifold.
 
Originally Posted By: horse123
Originally Posted By: DoubleWasp
Anyone who says a catch can does not do anything has never used one, or does not know that they have.

The amount of OEM applications of catch cans has multiplied over the past 10 years. The OEM is not always the sharpest tool in the shed, but the fact so many are jumping on board definitely says something.

In using catch cans, I have collected a fair amount of oil that would have otherwise coated my intake, or been burned in the engine.

It's not a life and death issue most of the time, but there is definitely room for improvement.


Or actually they use common sense and know that 99% of say 250k mile or 500k mile vehicles didn't have one and made out perfectly fine. Just because you see something happening doesn't mean it's doing anything that matters lol

Think about it like this. I can put a can that leeches some fuel from going to your engine and make the claim "it's collecting bad fuel that had contaminants!", but it's not actually doing anything. Same idea with catch cans.


Agree 100%
 
Originally Posted By: horse123
Originally Posted By: DoubleWasp
Anyone who says a catch can does not do anything has never used one, or does not know that they have.

The amount of OEM applications of catch cans has multiplied over the past 10 years. The OEM is not always the sharpest tool in the shed, but the fact so many are jumping on board definitely says something.

In using catch cans, I have collected a fair amount of oil that would have otherwise coated my intake, or been burned in the engine.

It's not a life and death issue most of the time, but there is definitely room for improvement.


Or actually they use common sense and know that 99% of say 250k mile or 500k mile vehicles didn't have one and made out perfectly fine. Just because you see something happening doesn't mean it's doing anything that matters lol

Think about it like this. I can put a can that leeches some fuel from going to your engine and make the claim "it's collecting bad fuel that had contaminants!", but it's not actually doing anything. Same idea with catch cans.



Some engines suffer from blowby more then others. I bet the 99% of 250k+ engines you mentioned probably don't have issues with excessive blowby.

The same can't be said about other engines which suffer from it and need the internals steam cleaned after 100k due to carbon build up EVERYWHERE.
 
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