fouled plugs

Discussion in 'Engine, Fuel and Exhaust' started by lnichols2, Aug 27, 2007.

  1. lnichols2

    lnichols2 Member

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    bike runs great in all gears and in throdle possitions but it cant set in traffic more than 5 min without killn the plugs.the mixture screw will onle make the rpm change if you turn it out not in, the screw dosent look damaged but it does look black at the tip.
    thanks les
     
  2. glider

    glider Veteran Member

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    First I would check the plug numbers to see if it is the correct one for the engine. If the heat range is too cold this would happen. I believe the plugs should be 6R12 for that bike but check to be sure in the owners manual.

    Secondly I would check the enricher to make sure it is not walking out from loose tension knob adjustment. It is a jet and not like the older plate in the carb so it would richen up the circuit in the carbs that may be already a bit rich and that's why you are loading up the plugs.
    http://www.hdtalking.com/fuel_and_carb_related_issues/814-adjusting_choke_knob_tension.html

    Lastly, your statement that you made "the mixture screw will only make the rpm change if you turn it out not in" Indicates to me either a damaged idle screw or a low speed jet that is too large and hence the fouling of the plugs.
    You should be able to stall the engine by lightly seating the idle mixture screw. To adjust it properly follow these guidelines. Warm the engine entirely then close the screw till it stalls the engine. Open the screw about 2 turns and restart the engine. Now adjust the screw to the highest and steadiest setting. Do this a few times finding the highest setting and notice when you do it if it is consistent. After you find the best setting, close the screw about 1/16 of a turn and go ride. This should give you the best mixture assuming you have the correct jetting in the carb.I would say that anything over a #45 low speed jet in that bike would be too big and probably the reason why you can't stall the engine with the idle mixture screw and also loading up the plugs.

    If all else fails, your float level may be a tad high and fuel could be dumping into the engine causing an overly rich mixture.
     
    Last edited: Aug 28, 2007
  3. lnichols2

    lnichols2 Member

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    thanks for the help. i found some trash in the mixture screw passageway,and someone has put a #45 low speed jet in it. i took the carb off and cleaned it and im in the prossess of putting in a new mixture screw and trying it again, if it will not tune out im going to go down to a # 42 and try again.
     
  4. lnichols2

    lnichols2 Member

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    thanks for the help. i found some trash in the mixture screw passageway,and someone has put a #45 low speed jet in it. i took the carb off and cleaned it and im in the prossess of putting in a new mixture screw and trying it again, if it will not tune out im going to go down to a # 42 and try again. float level checked out fine . will let ya know how it goes. thanks les
     
  5. glider

    glider Veteran Member

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    Keep one thing in mind too that there are mechanics that drill out a jet so if it says that it is a #45, It may be larger because it was drilled out. If you still have problems, replace it to be sure.

    It's hard to find a #45 jet in most places, here is a source that I use.


    http://www.jpcycles.com

    Just enter Pilot Jets in their search box. The #45 is part number 400-863
     
    Last edited: Aug 30, 2007
  6. MURPH

    MURPH Member

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    Gilder:i drained a couple of ozs. of gas out of the float bowel as you suggested and the bile ran much better for the next 5-6
    rides!On a 3 hour ride yesterday it did the smothering "thing" for about 4 miles and gradually came out of it. I am thinking of getting a new float-do I just order a flost ball as such? thanks, Gene.
     
  7. glider

    glider Veteran Member

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    I really don't think a new float will do anything. The old days of the hollow floats have been gone for years. These newer floats are solid and usually do not soak up fuel any.

    If draining the float bowl helped for 5-6 rides and the problem reappeared some time later and passed again, I would suspect some water or such in the tank itself. Try some dry gas in there before you go any further. Give it a good dose and you will find that the bike feels peppier also with the dry gas in there too. It sounds like this could be the problem and it should pass the water if it is water and your problems will be over.

    Also drain the float bowl again when you do this and again every couple of days till the problem subsides. The dry gas will pass the water but some may accumulate in the float bowl, problem is that the main jet is at the lowest point of the bowl and that's why you have the problems so draining it periodically will keep that clean.
     
    Last edited: Aug 31, 2007
  8. MURPH

    MURPH Member

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    Glider: What is dry gas? And do i just put it into the gas tank?Thanks, Murph.
     
  9. glider

    glider Veteran Member

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    Murph

    Dry gas is basically an alcohol and you just add it to the gas in the tank according to the amount of gas in the tank, it will tell you on the bottle. A bit over isn't anything to worry about either. It mixes with and changes the viscosity index of water so it can pass through the system instead of accumulating in the tank.

    It sounds as if you are on the right track if the bike ran better after draining the fuel from the carb.
     
  10. MURPH

    MURPH Member

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    Glider: I will try the dry gas and regular drains from the float bowel and will advise status then. Thank you for all your help and suggestions to date. Murph.