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PCV question... 850

1995-850NA
Due to an excess of oil loss, I took off the manifold, cleaned out the canister (it's only 2 years old), changed the rubber elbows (the ones from FCP were soft and 'jelly like'). No gunk or buildup that I could find. Ran the car for 2 days, noticed that one of the thin vacuum hoses was off of the flame trap (There is a 1/2" one and a thin rigid one). I reached under to put it back on...oil! There seems, to me , to be a lot of oil going into that flame trap...Is this supposed to be a wet area? I thought only gases passed through this..? Maybe the O-ring that I had on that flame trap body (I took it apart and put a new screen in...the other was excellent, but I had a new one on hand) was worn... Thoughts? I want all the oil to stay inside the engine...








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    PCV question... 850

    As was mentioned earlier the flame trap hard tube is probably plugged and it can't be cleaned out so it needs to be replaced. The connection nipple on the flame trap is also probably plugged but that can be drilled out.








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    PCV question... 850

    Throw away the flame trap.
    Clear out the plugged line from the flame trap to the vacuum tree.
    Clean out the EGR and the port where it bolts on the intake manifold.
    There's a DIY pictorial for this- find it with google. Bay13 maybe.
    Switch to synthetic oil.

    Bill








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    PCV question... 850

    I have read all your responses...Gee, I wish that I had done something wrong, so that I could correct it...but, alas, I have not. The hoses are all on the right nipples, I have used Mobil One since 1997... Today I did a 2 hour run with the car...after this, I put my hand under the flame trap (where the two parts meet...with the O-ring between them)...I came away with oil on my hand...So, oil is getting up there. Now, the question is: Is this 'normal'? Does oil get into this flame trap, and what I see is seeping past a worn O-ring? Or, is there a bigger problem? All ports were clean, engine exterior is clean, no smoke from dip stick... I have done everything you have mentioned....








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      PCV question... 850

      Not normal. Only fumes are supposed to go through to be burned, not oil. In fact, the passage from the engine to the oil separator is way above the normal oil level.

      Klaus
      --
      Always willing to listen, just not able to take direction.








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        PCV question... 850

        THEN WHY? OHHH, WHY? I don't want to take this thing apart again...I am sure that I did everything perfectly right...all hoses, cleaning.








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          PCV problem 850

          Is your engine running very hot? Did you notice an increase in oil consumption?

          If the hoses are routed backward on top of the oil separator box, that would explain it. Other than that, I cannot imagine why you would be drawing oil up the breather hose.

          Klaus

          --
          Always willing to listen, just not able to take direction.








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    PCV question... 850

    You have a short-term problem here that you are going to have to resolve pretty quickly or it will do long-term damage to your engine.

    I'll leave the solution of this short-term problem to others on this site who are far more expert than I.

    But long-term there is one thing you can do to mitigate this problem, in fact, eliminate it, and that is change to synthetic oil.

    I had the same problems that you and other have had with their 850s gunking-up. Every time I changed the oil I would take out the flame trap and it was caked solid with hardened bits of burnt oil.

    After replacing my engine as the end result of this problem, on my replacement engine I have used Mobil1 exclusively and changed the oil and filter about every 5,000 miles. I still have the flame trap in, and I look at it at every oil change, and I have never seen anything in the area of the flame trap resembling the hard crud that I used to see when I used dino oil. There is no gunk, no hard bits, nothing but relatively clean oil.

    Where I used to pop the oil filler cap and see darkened rocker arms and other components, now I see clean components bathed in translucent oil.

    There is no improvement I have made on any car that appears to have had a better payback than switching to synthetic. All of my cars now run Mobil1 and I recommend it, or an equivalent synthetic, to anyone who will listen.








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    PCV question... 850

    I wonder if you routed the hoses from the top of the oil separator box properly. The one closest to the block goes to the oil cap area. Just feel under the manifold to make sure. The diagram from FCP is wrong.

    Throw away the screen!

    An example for a turbo engine:

    http://www.matthewsvolvosite.com/forums/viewtopic.php?f=1&t=28487

    Klaus
    --
    Always willing to listen, just not able to take direction.








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    PCV question... 850

    Hi Alan,

    Canister? do you mean the oil trap?
    Did you clean the EGR valve and it's port to the intake manifold?
    (Mine was completely plugged here)
    The little tubing from the flame trap to the vacuun tree was plugged too.
    Leaving that plugged builds up too much engine pressure, then you can
    blow out oil seals for a nasty adventure.

    Everyone suggests: "Throw away that flame trap"

    Check all your vacuum lines and fittings for 1. leaks or unhooked
    and 2. for being plugged and 3. for being soft and mushy and able to collapse under vacuum (this being the same as plugged)

    Good luck, Bill







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