spark plugs keep fouling

Discussion in 'eXmark' started by jalawn, Jun 24, 2003.

  1. jalawn

    jalawn LawnSite Member
    Posts: 27

    We have two 2002 exmark riders. One is a HP 52" 23 koh. The other is a 61" 27 koh. Both need new spark plugs every 100 hours. the HP has 210 hours, and I am on my third set of plugs. The 61" has 80 hours on it, and I have replace the plugs tonight. Is this normal???? We take great care of our machines. My dealer said it was probably ran with the choke on at one point. I know that never happened. Not on BOTH! Why is this happening?

    Jamie
     
  2. eXmark

    eXmark Manufacturer / Sponsor
    Posts: 4,258

    Jamie,

    There are several things that could be causing the plugs to foul. First we can assume that it is fuel or air/fuel related because it was suggested that the choke may have been on while the unit was running. Fuel fouled plugs are generally appear to be black in color, sooty and dry.

    Other causes in addition to air/fuel mixture would be running a plug that is not hot enough, fuel additives or a weak ignition.

    If it's happening on both I would rule out the ignition. It is possible that you may have an improperly adjusted choke on both machines however. I would also try a hotter plug and if you constantly use one particular fuel supplier I might recommend switching for a while to see if the problem clears up.

    You should also make sure you run the machines at full throttle as much as possible. If the machine spends a great deal of time idler such as while picking up trash, warming up in the morning or while performing other functions you can cause the plugs to foul prematurely.

    Check those items and let me know what you find out.

    Thanks

    Terry
     
  3. jalawn

    jalawn LawnSite Member
    Posts: 27

    What plug would you recommend? One machine has the stock Champion RC12YC. I just put new plugs in the other machine - Autolite 3924. I really appreciate your help!

    Jamie
     
  4. MikeLT1Z28

    MikeLT1Z28 LawnSite Bronze Member
    Posts: 1,732

    i know you've probably already done this, but make sure your air filters and the precleaner are clean. less air means a fatter mixture.
     
  5. eXmark

    eXmark Manufacturer / Sponsor
    Posts: 4,258

    Jalawn,

    The next step up in Champion may be a bit high. I talked a couple of auto parts stores in the area and they recommend the Autolite that you have now.

    General opinion is that if the filters are clean, the choke is adjusted etc. the problem is probably fuel and simply changing brands may help. It's not that the Champion is a bad plug it just may not be best suited for the fuel on conditions you are currently experiencing.

    Thanks

    Terry
     
  6. jalawn

    jalawn LawnSite Member
    Posts: 27

    Terry,

    We don't normally use only one brand of gas. It is usually, whatever is closer or sometimes cheaper. We always use 89 octane. Maybe this regions gas isn't suited for champion plugs. I'll try the Autolites and see how they work. I really appreciate your help. This kind of customer service keeps me coming back!

    Jamie
     
  7. What color is the electrode on the fould out plugs?
     
  8. jaredslawncare

    jaredslawncare LawnSite Member
    Posts: 145

    You probaly need hotter plugs do have an NGK 4 or 5 in them now? my HP did and I went to a 2 and have had no problems since
     
  9. saw man

    saw man LawnSite Bronze Member
    from utah
    Posts: 1,021

    the last tech i talked to at Kawi. told me to use Premium gas
    because of this same problem with plugs.


    and i would switch to NGK plugs, i have not had good luck with Champion or Autolite
     

Share This Page