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Smoking out of valve cover breather

Discussion in 'The Garage' started by 85mudblazin, Mar 25, 2006.

  1. 85mudblazin

    85mudblazin 1/2 ton status

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    So I got the truck running and all. As it is warming it up starts smoking out of the valve cover breather holes. Whats the cause of this??
    Thanks
    -Chris
     
  2. hack500

    hack500 1/2 ton status

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    is it actually smoke or is it just water vapor(from condensation inside the engine)?
     
  3. 85mudblazin

    85mudblazin 1/2 ton status

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    I guess it could be just steam. I guess I just need to run it long enough and see if it goes away.
    I cant think of anything that would actually be burning in there.
     
  4. 89GMCSuburban

    89GMCSuburban 1/2 ton status

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    Blowby as well. First it is the moisture boiling out of the oil and after it reaches a good temp, it's blowby.
     
  5. daleearnhardt01

    daleearnhardt01 1/2 ton status

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    Hows your compression? Got a blowby problem perhaps?
     
  6. Russell

    Russell LB7 Tahoe Status Premium Member GMOTM Winner

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    PVC system hooked up and working?
     
  7. 85mudblazin

    85mudblazin 1/2 ton status

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    Well I ditched the PVC valve for just a regular breather so this could be my problem. Thing is a buddy of mine runs the same and he doesnt have this problem.
    Guess ill try putting it back on and see if this stops.
     
  8. hack500

    hack500 1/2 ton status

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    a reminder - breather on driver's side pcv on passenger's side.
     
  9. 85mudblazin

    85mudblazin 1/2 ton status

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    Every stock K5 that I have seen has had it on the driver side and a breather on the passenger side.

    But on a side note installed the PVC poof no more smoke:D
     
  10. muscle

    muscle 1/2 ton status

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    why is this?
     
  11. 78Suburban

    78Suburban 1/2 ton status

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    Mine is the opposite of that. Of course my motor isn't running correctly. But the last motor which did run ok, had the same setup.
     
  12. 79k20350

    79k20350 3/4 ton status

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    most ofe the times ive seen it, its been pvc on the pass side and vent on drivers. anyone know why theres a differance with some setups? and is one right?
     
  13. hack500

    hack500 1/2 ton status

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    the way I remember seeing it explained - was due to the direction of engine rotation. which seems to make sense.
     
  14. 78Suburban

    78Suburban 1/2 ton status

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    My truck has the breather hose run into the air intake on the passenger side. the Valve covers on both of the 350's I've had were set up with breather on the passenger, and PCV on the driver side. I'm 99% sure that's the way these two came from the factory, but I may be wrong
     
  15. diesel4me

    diesel4me 1 ton status Premium Member

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    having a PVC important...

    The PCV valve should never be eliminated..it will allow pressure to build up in the crankcase,cause oil leaks,even blow seals ..and it helps a great deal to eliminate water vapor in the crankcase and keeps blowby past the rings to a minimum..it also affects your carb's air/fuel mixture,its designed to run a bit rich,to make up for the vacuum "leak" the PCV creates..blocking it off will richen the mixture considerably,could lead to oil dilution..


    All the chevy V8's I had, the PCV was on the drivers side valve cover,AFAIK...I have seen many "re-located" and swapped sides due to custom valve covers,etc,with no bad effects..older 283's had a PCV valve that threaded directly into the base of the carb,where the power brake hose is usually located..

    I'm not sure if it really matters WHERE the PCV valve and breather is located,as long as you have BOTH,and they are functional,since other GM engines have them in the intake valley pan,etc..one qiuck way to blow a motor up is to not have a breather,but retain the PCV valve..it will suck the oil out of the crankcase slowly but surely,and lead to seizure..seen it happen many times on motors with "bling" aftermarket valve covers with no provision for a stock breather..some have no provision for the PCV valve,or an oil filler cap either!..:screwy:..
     
  16. 1985_K5_Silverado

    1985_K5_Silverado 1/2 ton status

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    I've got a breather cap on the passenger side (rear) and a PCV valve and hose on the driver's side (front, because it's easier to check and change up there!).
     

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