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25HP Kawi surging at no load

Discussion in 'Mechanic and Repair' started by guy48065, Jul 20, 2008.

  1. guy48065

    guy48065 LawnSite Member
    Messages: 22

    I just bought an '01 Country Clipper Zeton with 200 hours on it. Everything is in fine shape except the engine surges. Runs smooth under load but with the PTO off the engine speed hunts--at all rpms. Sometimes it settles down, sometimes not. Engine is a FH721V (seems to be a very popular engine).
    I've cleaned the carb exterior, checked linkages & sprayed cleaner inside. I haven't removed the carb because the muffler is in the way so that's a last resort. Air filter & plugs are new. I pried off the pilot screw caps & tried to richen the mixture but that didn't seem to help--but I may not be doing it right. The Kaw engine service manual doesn't have any adjustment procedure(!!).
    Might this problem go away if I throw a bottle of Techron in the tank or am I gonna need to take it apart further?

    BTW whats the factory pilot screw setting?
  2. chesterlawn

    chesterlawn LawnSite Senior Member
    Messages: 704

    Leave it alone. I've had 2 kawasaki's and thats the way they idle. Like you said under load they are fine.
  3. guy48065

    guy48065 LawnSite Member
    Messages: 22

    huh? You're kidding right? I can't imagine many would ever leave the showroom if they idle like that when new.
  4. MowerMedic77

    MowerMedic77 LawnSite Bronze Member
    Messages: 1,164

    If you slowly apply the choke but not fully choke the carb does the "hunting" stop? If it does(manually enriching the air/fuel mixture) then you will need to pull the carb and (soak) or clean out all the fuel and air passages to remove the blockage.
  5. guy48065

    guy48065 LawnSite Member
    Messages: 22

    No--choking doesn't help. And I need to modify my complaint/symptom: It surges with the PTO engaged, too. I just couldn't clearly tell with the muffs on. :rolleyes:

    So I'm assuming I have some crud stuck in the pilot circuit or jets and I'm going to need to remove the exhaust & then the carb & give it a good cleaning. Right?
  6. Phil G

    Phil G LawnSite Senior Member
    Messages: 844

    Looks like you're gonna have to bite the bullet and get the carb off. Unless you can drop the bowl and fire an air line up the main jet, just watch you don't damage the float assy. In truth it's best to remove it and clean thoroughly. When it's off check the flow from the tank and any fuel filters fitted.
    Good luck Phil :)
  7. BigFish

    BigFish LawnSite Platinum Member
    Messages: 4,157

    One thing to check, if the inline fuel filter is the small Kaw. unit , I would replace it with a larger kohler or generic one. I've run into that problem several times, the filter won't pass enough fuel. If ya open the carb up, note the main jet number/position, most R and L are diff.
  8. sawman65

    sawman65 LawnSite Senior Member
    Messages: 754

    is there a yellow tube coming off the carb? if so there was a update back in 03 that addresed this issue. seems the tube/vent can become clogged and will cause the problems you outline. the service bulliten also goes on to say you need to move the tube tword the back of the engine. the way to do this is to get a longer tube and run it under the starter. seem the airflow from the engine disrupts the flow from the vent also causing the problem you outlined. good luck.
  9. Phil G

    Phil G LawnSite Senior Member
    Messages: 844

    See....there's a man who reads his updates. Over here the manufacturers rarely admit to making a balls-up. :)
  10. guy48065

    guy48065 LawnSite Member
    Messages: 22

    The filter is a little cruddy so I bought a replacement to try.

    One of the things I ran across in searching the old posts here was about the vent tube being in the strong airstream. I replaced it and moved it around but no change.

    I ordered the gaskets I need to work on the carb so this looks like one of my weekend projects.

    Anyone know if I can get the carb off without removing the muffler? Are the long studs holding the carb together & to the manifold loc-tited in place?

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