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Kohler CH20S Command not running right.

Discussion in 'Mechanic and Repair' started by Impressions Landscaping, Nov 7, 2012.

  1. Impressions Landscaping

    Impressions Landscaping LawnSite Member
    Messages: 215

    I ordered all the parts today to do the rings and head gaskets. It runs like garbage, however, I did get it the issue with the carb to clear up. I took the carb apart and found a black rope like thing in the bowl area...no bigger than the tip of a pencil. I blew the carb out and put it back together and ran it and it still ran like crap, better but not great and still needed the choke. Mind you I have a brand new fuel pump on it and verified that it is pumping fuel and blew the lines out as well when I had the carb apart. I noticed that while it was running it would run the fuel filter almost completely out of fuel. I put a smaller fuel filter on and it fixed the issue with needing the choke to keep it running. However, the motor does need to be rebuilt and that's what I'll be doing next week. Anything you guys recommend to look for while I have the motor apart...or anything I should replace? I'm doing all the gaskets as well while the engine is apart. I appreciate all the help so far guys!
  2. ericg

    ericg LawnSite Silver Member
    Messages: 2,792

    Check to see how good the valves are seating in the head. They may have to be ground as well as the seats. I would use a micrometer on the bore to make sure that it is within spec. Otherwise new rings will not do anything.
    Post back what you find.
  3. Impressions Landscaping

    Impressions Landscaping LawnSite Member
    Messages: 215

    Sounds good to me, I'll be pulling it apart sometime this week and I'll let you know what's going on inside and what my specs are. Thank you again!
  4. VegetiveSteam

    VegetiveSteam LawnSite Senior Member
    Messages: 296

    You may also want to check for a flat cam lobe.
  5. Impressions Landscaping

    Impressions Landscaping LawnSite Member
    Messages: 215

    Pulled the motor apart. I'm surprised this thing even ran. On top of the front cylinder needing rings and to be honed out, the back cylinders head gasket was garbage. No idea how this motor even ran. The inside of the motor was pretty clean, with the exception of the obvious oil buildup on the valves on the front cylinder head. There's a guy who I'm buddies with who repairs a lot of small engines and he checked the clearances on the valves and also the wear on the cylinder walls. Everything checked out ok, so I'm just going to re-hone both cylinders and put a set of rings into it. Aside from the obvious issues with the compression on this motor, it was very very clean inside. I've always kept up with the oil changes, but come to find out while I was gone on vacation back in September one of my guys changed the oil and didn't put enough in, and didn't realize it until someone else checked it. My only assumption is that it overheated and cooked the head gasket and most likely ruined the front oil ring that was probably already pretty worn out to begin with. This motor has around 1300 hours....that reads on this hour meter. The first hour meter broke around 900-1000 hours.

    Also PistonSlapper. I was getting a "fluffing" sound when I shut the motor down on the rear cylinder. You were correct with the head gasket.

    Thanks again for everyone's help. Anything I need to watch out for putting it back together?? Last one I had apart was to far gone to put back together, so I bought a new one.

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