1. Missed the live Ask the Expert event?
    Catch up on the conversation about enhanced efficiency fertilizers with the experts at Koch Turf & Ornamental in the Fertilizer Application forum .

    Dismiss Notice

Engine Repair Suggestions

Discussion in 'Mechanic and Repair' started by Hpreacher, Jun 4, 2009.

  1. Hpreacher

    Hpreacher LawnSite Member
    Messages: 5

    I have a 25 HP twin cylinder Kohler Engine on a 60" X-Mart Rider Mower that is
    burning a lot of oil. It has too much crankcase pressure and blows the oil out
    of the vent hose that goes into the carburetor. I have pulled the heads and
    checked the rings on the pistons and they seem good. I'm wondering if any-
    one has had the oil-using problem on this Kohler engine and what you might
    have done to correct it.
  2. ALC-GregH

    ALC-GregH LawnSite Fanatic
    from PA
    Messages: 7,052

    I wouldn't rule out the rings. Chances are that's the cause of the problem. If it's building too much crank case pressure, then the rings are allowing blow by to happen. How many hrs and what oil have you been using.
  3. MowerMedic77

    MowerMedic77 LawnSite Bronze Member
    Messages: 1,164

    I would check the breather reed valve, it is probably broken.
  4. Hpreacher

    Hpreacher LawnSite Member
    Messages: 5

    I purchased new pistons and rings and am installing them. I will check the
    reed valve. This valve was bent a little and I tried flattening it back out.
    Is it possible that the reed is not seating properly and allowing it to leak?
  5. Hpreacher

    Hpreacher LawnSite Member
    Messages: 5

    You ask about the oil I am using; I am using 5/30 weight synthetic oil. We use it in all the
    rider mowers, because the manufacture suggested it.
  6. MowerMedic77

    MowerMedic77 LawnSite Bronze Member
    Messages: 1,164

    It should be flat and resting on the hole in the block, there should be a bent looking hold down bracket with one screw that secures it to the block.
  7. Hpreacher

    Hpreacher LawnSite Member
    Messages: 5

    Thanks for your quick replies, I haven't got the engine back together yet, but I'll let you
    know what happens. This engine has hyd. valve lifters and the exhaust valve was burnt
    so I relapped it. The valve didn't appear to be warped.
  8. VegetiveSteam

    VegetiveSteam LawnSite Senior Member
    Messages: 296

    Look closely at the head gaskets if you still have them and didn't tear them up too badly when you took them off. Also does it show signs of oil usage on both cylinders? A quick look at the spark plugs should answer that question. If it looks like it was mostly on one cylinder I would probably blame the head gasket. You don't say if this is a vertical shaft or horizontal shaft engine. Kohler did see a few reed valves cracking or breaking on some vertical shaft engines.
  9. Hpreacher

    Hpreacher LawnSite Member
    Messages: 5

    Thanks for the information. I installed new pistons and rings, and also
    new head gaskets. This is a horizontal shaft engine, two cylinder.
    The left side showed it to burning oil, on the spark plug. The reed valve
    was good. I have got it together and out working. I will see if what I did
    corrected the oil-burning problem and let you know.

Share This Page