Kohler 20hp wont stay running

Discussion in 'Shop Talk' started by Dahc, Jul 15, 2007.

  1. Dahc

    Dahc Don't Tase me, bro!?!

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    My dad has a toro groundmaster 120 with a Kohler 20hp engine. The other day he let a neighbor use it and it quit running. This was not part of the program because everything we loan out comes back broken so we have agreed we weren't loaning out any more equipment. Anyway, at first he thought the neighbors gas may have had water in it. It turned out not to be the case and so we thought it might be the fuel filter. As we drained the gas, there was no obstruction of the fuel coming from the line and the filter appeared to be clean.

    This is the deal: When we crank it, it runs for about 2 seconds and then just stops. There is no sputtering or anything, it just shuts off but starts every single time. If we try and start it at full throttle, it will not start. If we try to start it with the choke on, it will not start either.

    If we try and start it as it is supposed to be started (minimum throttle, no choke) it cranks every time but shuts off after 2 seconds. There is one fuse which appears to be ok.

    Does this sound like a fuel pump issue? It has the type that is operated by a vacuum line. A vacuum line, one from the tank with the inline filter and one going to the carburetor. Being as engine ignorant as I am, I would say it could only be the fuel pump or the carburetor. Does this sound familiar to anyone? Could it still be electrical even though the one fuse is good?
     
  2. bill not in oh

    bill not in oh Well-Known Member

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    My Kohler powered Gravely had similar symptoms. I started replacing electrical parts - coil, condenser, points... Then out of pure frustration I bought a second new coil. And it ran. Apparently I had simply got a bad [new] coil. Mine would run [poorly] for more than two seconds, but had similar starting issues and would die probably within 12-15 seconds.
     

  3. Bearfootfarm

    Bearfootfarm Hello, hello....is there anybody in there.....? Supporter

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    I would suspect the carbeurator or the fuel pump. If it were electrical I doubt it would run at all.
     
  4. Old Vet

    Old Vet In Remembrance

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    to see if it is the fuel pump. Get a electric pump from a parts place (around $8 dollars). Just replace the pump with the electric one and try it. wire it from the battery. Be sure that it is properly wired. If it is then either get a new pump and replace the original one or use the eletric one with a fuse link in the wire.
     
  5. moopups

    moopups In Remembrance

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    Have someone try to start it as you are spraying WD 40 around the carb base, any different reaction will pinpoint a vacuum leak. To me it sounds like a lack of adequate fuel.

    If you get a reaction then try spraying into the mouth of the carb while trying to start. If spraying stops and the engine stops together, you have a fuel supply problem.
     
  6. Countrybumpkin

    Countrybumpkin Well-Known Member

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    had a 20hp Kohler, and it did the same thing-was the fuel pump. Tried everything else first, but after replacing the pump, ran like a champ!
     
  7. Dahc

    Dahc Don't Tase me, bro!?!

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    Thank you all for your posts. We will get right on it next thursday when dad returns.
     
  8. Rocky Fields

    Rocky Fields Failure is not an option.

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    Hey.

    Air cleaner could be dirty.

    Did you disconnect fuel line from carb to see how much gas is coming out? Do this before replacing fuelpump.

    Is fuel shutoff open all the way?

    RF
     
  9. Jim S.

    Jim S. Well-Known Member

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    Dahc, depends on which 20 hp. Is it a Command V-twin or the older K-series pancake horizontally opposed engine?

    If a V-twin, the carb has a fuel shutoff solenoid in the base. There is a single wire running to it. Whenever the engine key is ON, there is juice holding the solenoid plunger open and allowing gas to flow. When you turn the key to ON and listen by the carb, you should hear a click of the solenoid coming on. That solenoid must function, and the small passages inside the carb to it must be clear. If not, you will get exactly the conditions you just described.

    It is pretty easy to remove, check and clean in there. Use air on the passages.
     
  10. Dahc

    Dahc Don't Tase me, bro!?!

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    It was the ignition switch. lol. It kept turning itself off. How that happens, I have no idea. While I was posting the question dad took it to the shop. I never looked in the shop at it and just figured it was still there. I guess he just had to spend some money or something.

    Thanks for all of the help everyone. I would have surely replaced the fuel pump if it had been up to me.