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5.3L LT motor oil catch can

Discussion in 'Automotive / Motorcycle Chat' started by pronstar, Jun 21, 2020.

  1. pronstar

    pronstar TGT Addict TGT Supporter

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    I had been dumping this thing out randomly, but I wanted to see exactly how much oil it has been collecting over time.

    32e37c60fbce1a3ab2c951891b28fc12.jpg

    After 5k miles...a lot more than I thought.

    Time to install a catch can on Mrs Pronstar’s Suburban, because I don’t want this much crap going back into the intake on a DI motor (which is a terrible solution IMHO).



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  2. SQLGeek

    SQLGeek Wheel Gun Nut TGT Supporter

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    That's oil blowing past the piston rings? What is it you're having to empty the oil out of?
     
  3. candcallen

    candcallen Purveyor of Snark Humor and Truth.

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    Changes the point of vacuum so oil isnt directed directly back into the intake stream as part of emissions. In direct injection or engines with an intercooler it helps keep valves free of deposits.
     
  4. Brains

    Brains IQ: 47

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    If oil blows past the rings you'll see it in the exhaust.

    This is the oil mist and vapor generated in the crankcase. The LT motors also have piston oil squirters that direct oil to the bottom of the piston to cool them down. That causes a portion of the oil to boil off and that vapor is captured by the PCV, and that's in addition to the normal amount any motor generates as oil splashes off the crank onto the hotter parts of the rotating assembly.

    SOP on basically every car on the planet is to pipe the PCV into the intake, and most people never notice the amount of oil that goes "missing" unless they look.
     
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  5. pronstar

    pronstar TGT Addict TGT Supporter

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    Yeah it’s a mix of oil and water. When folks with DI engines have issues with intake-valve deposits, this is the source.

    One of these days I’m gonna pull the intake manifold off and take a peek at how much crud has accumulated in the backside of my intake valves.

    Some good info here:




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