Oil coming into carb

Discussion in 'Mechanic and Repair' started by jlslavey, Jul 20, 2007.

  1. jlslavey

    jlslavey LawnSite Member
    Posts: 9

    I have a 18hp Kohler command, recently I've been getting a lot of oil into my air filter. I took off the breather and cranked the engine over, oil shot up through the rubber tube that goes into the bottom of the breather assembly. Can anyone tell me whats going on? I've seen mist come through the tube but this was a steady stream of oil. Help!!!
     
  2. newz7151

    newz7151 LawnSite Silver Member
    from Tejas
    Posts: 2,419

    Did you...... overfill it?
    If not, replace the breather assy.
     
  3. DOLMARatOS

    DOLMARatOS LawnSite Member
    Posts: 173

    If it isn't a breather assembly it could very well be a blown head gasket. Not enough to notice a loss in power but sufficient to pressurize the crankcase and force the oil out.

    Only true way to diagnose is to pull the cylinder head. sorry.
     
  4. newz7151

    newz7151 LawnSite Silver Member
    from Tejas
    Posts: 2,419

    Or hook up the leakdown kit and see what blows.
     
  5. DOLMARatOS

    DOLMARatOS LawnSite Member
    Posts: 173

    You may get leakdown out the oil tube and breather. At that point, pull the valve-covers, drain the engine oil and spray some light oil down the cylinders and watch down the pushrod tunnel for bubbles.
     
  6. jlslavey

    jlslavey LawnSite Member
    Posts: 9

    I did a compression check and one was 163 the other 175. I'm not too familiar with this part of the engine . I took off the breather cover and inspected everything. The reed was ok, and I could not see anything else that could be broken. Am I correct in thinking that when the oil comes into the channel for the oil sended unit then it overflows in the reservoir where the filter is, then proceeds to drain out the hole in bottom of the reservoir? About how fast should the oil leave through this hole if the engine is not running?
     
  7. thecrankshaft

    thecrankshaft LawnSite Member
    Posts: 172

    Vertical or horizontal?
     
  8. jlslavey

    jlslavey LawnSite Member
    Posts: 9

    its a horizontal crank, I included other info in another topic that may or may not help, thanks for the reply
     
  9. thecrankshaft

    thecrankshaft LawnSite Member
    Posts: 172

    Horizontal - that means the reed valve and breather filter are located underneath the breather cover below the carburetor. I would do a crankcase vacuum test; you may have pressure in the crankcase.
     
  10. jlslavey

    jlslavey LawnSite Member
    Posts: 9

    Here's what I've done so far, checked reed valve and new gasket installed, I just went out and tried a leaktest, I took off the pressure on all the valves(by loosing up rocker arms) tried it with them tight but kept turning engine over, so with all pressure off valves, I blew about 60-80 lbs air into plug hole, (sealed with a compression test fitting so as too have no leaks) I felt air coming through the carb, not a lot but enough to feel it, and felt like it might have been coming around the valve area. any ideas what might be going on ( such as valves not sealing ) just a wild guess. I've rebuilt car engines but this baby is a little different> thanks for any info you can give me.
     

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