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CH25 throttle response

Discussion in 'Mechanic and Repair' started by Ax Man, Jul 24, 2002.

  1. Ax Man

    Ax Man LawnSite Senior Member
    Messages: 446

    Lately my motor has been acting up. When I rev it up with the blades engaged, it sputters blowwing black smoke too.
    I have cleaned the plugs, Checked float level and for dirt in the carb.
    Is it common for the "smart spark" to cause problems like this?
    It is more common when I get to a lawn, not too often when re-engaging on the same property.
    (it has 530 hours and air filter is clean as a whistle too)
  2. khouse

    khouse LawnSite Bronze Member
    Messages: 1,465

    look down the carb to make sure the choke is open.
  3. olfrt

    olfrt LawnSite Member
    Messages: 48

    I had an engine (25 Kohler) that had a serious problem with the blowing black smoke and stumbling. It was almost always on start up after the engine was hot though. never did completely solve the problem.

    did however find that the air filter was dirty from the inside out (from backfiring throuth the carb). It fooled me bad I checked the air intake system from the end of the air intake to the outside of the main air filter on top of the carb it was clean as a whistle.

    I'd sure check that air filter on the inside
  4. Ax Man

    Ax Man LawnSite Senior Member
    Messages: 446

    Guess what? I was going back through things today and did check the inside of the secondary filter and it is coated with back fire juice.
    (I'm not sure of the technical term)
    I'll replace it and try try again!

  5. Ax Man

    Ax Man LawnSite Senior Member
    Messages: 446

    That was the answer!
    It runs like new again, but it should with only 550 hours.
  6. olfrt

    olfrt LawnSite Member
    Messages: 48


    Walker has gotten the air intake system so good that simple things get harder to find.

    Glad to hear that your motor is running strong

    Let the grass fly :blob3:

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