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Oil Catch Can are useless

Discussion in 'Gen 3 Prius Main Forum' started by abubin, Jan 30, 2023.

  1. abubin

    abubin Member

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    Recently there is a post in reddit at Prius sub where someone posted a question on OCC.

    Someone replied that OCC are not needed as it does not help for oil consumption issue and are useless. He is aa Toyota Master Tech with many years of experience.

    So I asked further questions and he replied with details why it's useless.

    Would like to know what you guys think.

    reddit.com/r/prius/comments/10nrp4a/this_is_what_is_feed_into_your_engine_without_an/
     
    #1 abubin, Jan 30, 2023
    Last edited: Jan 31, 2023
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  2. Noahdoge

    Noahdoge Active Member

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    They’re far from useless. I love having mine and being able to empty it every 2,500 miles and see all that oil and gunk not get sucked back into the intake and clog up all the hard work I did to clean the egr. BUT… an OCC is only for those who are super ocd about their Prius. I would never recommend to any regular Prius owner to install one. Not checking it and having it over full for 20,000 miles will be far worse than just leaving it stock. The majority of North American drivers don’t check their oil level ever (probably don’t even know how to open the hood). Then there’s the problems of the occ freezing in the winter and causing issues. So long story short it’s the most useful useless thing you can install to your Prius.
     
  3. PriusCamper

    PriusCamper Senior Member

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    Thanks for the heads up... Looking forward to unmastering this particular Toyota "master" mechanic (for entertainment purposes only).
     
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  4. PriusCamper

    PriusCamper Senior Member

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    Bad link to this above... Here's the correct link: reddit.com/r/prius/comments/10nrp4a/this_is_what_is_feed_into_your_engine_without_an/

    Please go there and explain to the "Toyota Master Mechanic" that cleaning EGR every 100K miles is irresponsible and not soon enough and so is his knowledge of an oil catch can.
     
    #4 PriusCamper, Jan 31, 2023
    Last edited: Jan 31, 2023
  5. Grit

    Grit Senior Member

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    It reduces blow by slowing down carbon deposits, not reduce or stop oil consumption. The mechanic is looking for customers to bring in a car that needs work to be done, catch can equipped Prius are on the road longer w/o mechanics help.
     
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  6. Georgina Rudkus

    Georgina Rudkus Senior Member

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    There are many newer designed engines with built in "oil catch chamber." Because of the need not to add an additional frequent low mile interval service requirement that would create a negative image for the uninformed owner, these units meter the oil residue caught in them basically back into the engine to be burned.

    A well maintained OCC by a knowledgeable and informed enthusiast will always increase engine life over those vehicles without and oil catch system or one that meters the catched residue back to the engine.

    Early cars vented the effluent to the outside, which increased pollution. Today, that is not an option.
     
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  7. PriusCamper

    PriusCamper Senior Member

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    Yep... Fossil fool industry loves convincing everyone that burning as much nasty as possible is a virtue and this "master mechanic" is a loyal worshiper of this particular religious dogma.
     
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  8. PriusCamper

    PriusCamper Senior Member

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    Yea... Getting people to check the oil is a nightmare... All the excuses I've heard are stomach churning. The red triangle blinking on corners and during hard breaking is as close to the dipstick these fools are willing to get and that's when there's less than 2 quarts of oil left.

    What's worse, I tried to sell Oil catch cans to my friend who owns a taxi cab company and at the time owned a fleet of Gen 3 Prius. He told me he's not willing "to empty a can in the engine compartment." Meanwhile the Toyota Stealerships swapped out more than one Gen3 engine for him. It's why he moved on to run a fleet of hybrid Camry instead.
     
    #8 PriusCamper, Jan 31, 2023
    Last edited: Jan 31, 2023
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  9. TMR-JWAP

    TMR-JWAP Senior Member

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    I'm curious. How does one check oil level? Do you remove the dipstick and wipe it clean with a paper towel or rag?

    Where does that paper towel or rag go afterwards? Certainly not into the trash? Wonder how many oily rags and paper towels get thrown in the trash every day? or does everyone have an oily waste disposal container in their garage? Maybe the people who don't check their oil level are just more environmentally conscious than most?
     
  10. abubin

    abubin Member

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    "Problem is some oil is supposed to enter the intake, it's the reason the oil/air seperator (the car already has a "catch can" built into the system" will not seperate all oil mist .

    All the external catch can does is condense unburned hydrocarbons that would have been burned, and unnecessarily condense water.

    The catch can is not extending the life of the motor, it's not doing anything at all except adding to physical pollution.

    Its like those EMP protectors, they give the illusion of benifet without actually doing anything."

    If I am reading this correct, he is saying OCC is making things worst by condensing the oil mist in the air. If that is the case then there should be more oil pool in the intake manifold compared to before OCC installation?
     
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  11. PriusCamper

    PriusCamper Senior Member

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    As in negligence can sometimes be a virtue. :) Or rather, even a broken clock is correct twice a day!
     
  12. PriusCamper

    PriusCamper Senior Member

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    Yeah, you don't need an oil catch can when Toyota uses the entire intake manifold to do that job... I mean you could hold a lot more oil in an intake manifold than an oil catch can. :) Draining it however... That's a problem.
     
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  13. Mendel Leisk

    Mendel Leisk Senior Member

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    In my case such rags go back in the oil change tool corral, basically the oil catch pan (which I rarely use), along the various funnels, oil filter sockets, squegees, old tooth brushes or two, and several dowels for helping to push cleaning rag through funnel spouts).

    I use a "shop towel", over and over, till it gets a little disgusting, at which point it's relegated to mopping up spill duty. Eventually I'll pull a latex glove off inside out while holding such rags, tie it in a not and add to the carbage.

    So yeah, it eventually ends up in a landfill (aka dump), but not that often.

    Stuff like used brake cleaner fluid I'll pour over a small tray of kitty litter, put it out the back door to evaporate for a week or two, then bag for the dump.
     
  14. TMR-JWAP

    TMR-JWAP Senior Member

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    I use a "shop towel", over and over

    I prefer to walk into the house, grab one of the kitchen towels and add it to my garage collection. After a few times, it gives the wife an opportunity to buy ones with fresh new designs.
     
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  15. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah I've got a small plastic garbage can full of old clothing remnants, used to use those exclusively. More durable than "shop towels", which are basically strengthened paper towels I think.

    Do you recall this Priuschat wag? I'm paraphrasing:

    To change the oil I run the front end up on a curb near a storm drain, let it rip, then mop up splashes with any eagle that flys by.
     
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  16. bisco

    bisco cookie crumbler

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    most toyota mechs don't understand the problem because toyota refuses to admit there is one
     
  17. Georgina Rudkus

    Georgina Rudkus Senior Member

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    Vehicle manufacturer do not install oil car cans so they can brag about how less maintenance their products. I recall one gasoline powered lawn mower manufacturer brag that their lawn mowers' engines never need their oil changed.

    BMW used to have an oil change interval of 15,000 miles with disastrous results. In some cases the oil filter material shredded and clogged the engine intake.
     
  18. PriusII&C

    PriusII&C Active Member

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    It looks like OCC is an emotional subject to discuss.

    My main purpose of visiting PriusChat is to learn and share experience/data/knowledge, not emotion. I believe that a properly installed/serviced OCC is harmless. The question is how useful it is. For example, how much (percentage-wise) consumed oil is catched by the OCC for a Prius engine with and without significant oil consumption?

    Based on a few examples people shared on PriusChat, my estimate is around 15%, give or take. But that is on a very limited sample set. I'd like to see more data.
     
  19. Eddie25

    Eddie25 Active Member

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    I'm kind 50/50 on my catch can. Sure it catches a lot, mostly water... but it doesn't reduce oil consumption (as we all know) and from my experience doesn't decrease time between a necessary intake manifold cleaning. I got less than 40k miles between intake cleanings with one (egr runner was fully clogged). I still get the same amount of gunk in my intake under the throttle body as well. That's all fine and dandy but what I really dislike is that in the winter I have to check it every 1200 miles, it's usually only half full but I've had it be completely full and I like to be safe.

    I'll leave it in, but if I could do it over, I'd pass. Just my thoughts.
     
  20. Mendel Leisk

    Mendel Leisk Senior Member

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    What can are you using?