PCV vs catch can vs second breather

[Byrds8]

I know this is an old thread but a lot of times its not just oil you are pouring out of the catch cans. A lot of times its condensation mixed with other items to include maybe some oil. Through the years, I have ran catch cans on a couple of vehicles. Always dumped them and thought they were great. However, one day it dawned on me, I never lost a drop of oil when measuring with the dip stick. Needless to say I stopped using them after that realization.

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[AnnDee4444]

Catch cans are potentially more advantageous on direct injection engines such as the 2.0. The 3.6 is port injected therefore the gas/air charge will basically keep in check (cleaning action) any PCV oil introduced into the intake track.
The backside of the intake valves in a direct injection engine don't benefit from the cleaning action of fuel passing by them.
This in turn becomes a serious maintenance issue say 70-90K miles later when the intake valves in these DI engines get completely carbon fouled, and need an expensive walnut blast etc. to clean. And of course it's a reoccurring problem in DI engines.
This is a topic I don't see discussed much among the 2.0 members.... but it's coming!

Looks like the 2.0 doesn't have much blowby at all.

https://www.jlwranglerforums.com/fo...2-0t-catch-can-kit.27322/page-24#post-1004586

 

[Gear_AU]

Did you find a solution? I'm looking for something that works as I'm about to put a replacement 3.6 back in after the first one failed due to the oil ingestion.

 

[Trav73]

I installed the UPR catch can about 25K miles and 5 oil changes ago. Getting close to a full quart of oil or whatever it is. I empty the catch can every 2K miles or so., it's catching something. 2021 JLUR 3.6 standard.

 

[roaniecowpony]

Must be slow out there to have to revive this one.

That said, I bought the Teraflex "inverted oil system" I need to put it on. I don't do a lot of stupid steep stuff, but eventually that stuff catches up to you.

 

[roaniecowpony]

I installed the UPR catch can about 25K miles and 5 oil changes ago. Getting close to a full quart of oil or whatever it is. I empty the catch can every 2K miles or so., it's catching something. 2021 JLUR 3.6 standard.

The PCV system is doing what it's supposed to. It's a closed loop specifically because oil vapor does get by and is intended to be consumed by the engine. If you put a large enough of a chamber and refrigerate it, it will condense even more oil out of the vapor. This can go on endlessly. That is to say, a catch can doesn't get it all, it just gets a bit more.

 

[nositting]

Looking for thoughts or reviews on the PCV issues with the 3.6. I understand the catch can options and kits available but I don’t feel they fix the problem of oil getting past the PCV and into the intake once the can fills up. I’ve searched and can’t find much input on the breather options other than the marketing materials for the companies.
It looks like teraflex has an updated kit and UPR has a breather. Anyone using these or seen them work in real life? I’m also open to anyone who has a permanent fix to the PCV being in the back of the valve cover allowing oil to pass on inclines.

Teraflex
https://teraflex.com/jl-jt-3-6l-crankcase-vent-system-kit.html#

UPR
https://www.uprproducts.com/19-21-3...e-way-valve-cover-crankcase-breather-kit-upr/

UPR has a drain line (3’ ?) you can attach to the bottom of the catch can with a stopcock. this allows it to hold more, drain quicker/easier and i imagine could drain while hot. perhaps something to look into?

 

[roaniecowpony]

Catch can...solution looking for a problem? ~34k miles and no buildup of carbon on the intake valves or ports.

 

[Trav73]

So, I'm admitting that I'm sucker for cool looking gadgets to put on my Jeep. I ordered an oil cap breather, but wasn't thinking about the mess these things could make under the hood. Anyone using one or have experience with these in a 3.6l V6 Pentastar? Now hesitant to use this thing if it's going to slowly mist the inside of the engine compartment with vaporized oil.

 

[5Petes]

UPR has a drain line (3’ ?) you can attach to the bottom of the catch can with a stopcock. this allows it to hold more, drain quicker/easier and i imagine could drain while hot. perhaps something to look into?

I installed one and just empty it often due to the volume it collects.

Catch can...solution looking for a problem? ~34k miles and no buildup of carbon on the intake valves or ports.

I am less concerned about the intake system on my 3.6 than I am on my wife’s 2.0 because of the injection process. I wanted this for the hydrolock issue which is why my questions were about capacity, the Teraflex valve, and moving the PCV from the back of the valve cover. Blowing a hole in side of one engine block will make you gun shy of it happening again outside warranty.

 

[Trav73]

Quick update:
The contents on the left are from the catch can, emptied at about 1.3k miles after installing the UPR oil cap breather. Note that this was during the winter months of December to January. I've been emptying this catch can for over two years (large container on the right) and have never seen this milkshake-like content before. I understand it's normal, and the oil on the dipstick looks fine. I have noticed that the valve ticking has been much less or almost non-existent lately—possibly a placebo—but it's really not ticking intermittently like it used to at idle. I'm sending the current oil in for analysis just to be sure and compare it with my previous results. Also, no oil mess under the hood from the breather cap like I had previously expected.

 

[roaniecowpony]

Quick update:
The contents on the left are from the catch can, emptied at about 1.3k miles after installing the UPR oil cap breather. Note that this was during the winter months of December to January. I've been emptying this catch can for over two years (large container on the right) and have never seen this milkshake-like content before. I understand it's normal, and the oil on the dipstick looks fine. I have noticed that the valve ticking has been much less or almost non-existent lately—possibly a placebo—but it's really not ticking intermittently like it used to at idle. I'm sending the current oil in for analysis just to be sure and compare it with my previous results. Also, no oil mess under the hood from the breather cap like I had previously expected.

The fluid on the left has a high water content. It's just a product of the particular environmental and operational conditions during the test period.

 

[vetygud]

I've had catch cans on my corvettes and pickups and this is normal in a cold climate during the winter. Come summer it will be almost straight oil. You need to check and drain the catch can weekly from all of the condensate during the winter months.

 

[roaniecowpony]

Quick update:
The contents on the left are from the catch can, emptied at about 1.3k miles after installing the UPR oil cap breather. Note that this was during the winter months of December to January. I've been emptying this catch can for over two years (large container on the right) and have never seen this milkshake-like content before. I understand it's normal, and the oil on the dipstick looks fine. I have noticed that the valve ticking has been much less or almost non-existent lately—possibly a placebo—but it's really not ticking intermittently like it used to at idle. I'm sending the current oil in for analysis just to be sure and compare it with my previous results. Also, no oil mess under the hood from the breather cap like I had previously expected.

You could heat the slurry on the left and perkolate the water out of it, leaving just oil.

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