Bob-cat 18hp Kohler fuel problem

Discussion in 'Mechanic and Repair' started by Cooter, May 30, 2007.

  1. Cooter

    Cooter LawnSite Senior Member
    from NE Iowa
    Messages: 510

    I have an older Bob-cat T3100 that I haven't had out in a while. Now that I've gotten it out and have an interested buyer it is having problems with fuel delivery problems I believe. The fuel filter will rarely stay full. It will run alright for a while then it will slowly run out of fuel. You can stop let it catch back up and it will be fine for a minute or two. Is there a type of cam or something that runs the fuel pump that may be worn? Or could this possibly be a carb problem? I am unsure and would lke to get this sold. Thank You for any advice.
  2. ArchZangel

    ArchZangel LawnSite Member
    from Florida
    Messages: 24

    What model kohler 18 do you have?
    Command, Magnum or k-series
    Model and version will dictate mechanical or pulse pump
    To test fuel pump. Remove hose between pump and carb. Put carb side of hose into container. Crank engine, fuel should flow into container quite easily.

    Sounds like a restriction in the fuel lines before the fuel filter.
    1. Shut-Off fuel supply at fuel tank
    2. Disconnect fuel filter
    3. Put hose from tank in container.
    4. Turn fuel on
    5. Gas should freely flow into container
    IF not
    1. Fuel cap vent not working
    2. Trash and/or corrosion in fuel petcock,
    3. Garbage in fuel line itself
  3. Cooter

    Cooter LawnSite Senior Member
    from NE Iowa
    Messages: 510

    Thanks for the suggestions. It is a magnum engine. It seems to run fine after a new fuel filter and lines. I was just worried after the interested buyer installed a new mechanical fuel pump that it may be the cam or whatever runs the pump. I really have no idea why he didnt do the easy stuff first. One thing that may need attention now, after I ran it for about a hour and turned off the pto while driving back to the shop it backfired several times rather rappidly. I stopped it stopped backfiring and I went back to the shop. I cleaned the carb and installed new plugs and ran it for another hour while this never happened again. I guess I will have to run it some more to tell.
  4. Bill Kapaun

    Bill Kapaun LawnSite Senior Member
    Messages: 956

    Maybe a few drops of water in the fuel got sucked up by the carb?
    Throw a few oz. of Gas Dri in the fuel.

Share This Page