Ghost in the tractor... (Engine suddenly quits with motion)

   #1  

macindude

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Oct 4, 2014
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Hubertus, WI
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Simplicity Legacy
OK, this one's a bit weird to me.

I have a late-90s Simplicity Legacy (prior to the XL model) with a Kohler engine. I was working in the yard, driving around a corner when boom, my engine just quit suddenly. It was as if I had shut it off. No sputtering, no nothing.

After looking at it for a couple minutes to make sure there wasn't anything that should have done that, I decided to see if it was a fluke. I was able to start it right back up, but after 5-10 seconds it quit again. Started it a third time, and it lasted maybe 3-4 seconds, a fourth time and it lasted only about a second or two. Let it sit for a bit while I pondered what might cause that, and tried one more time - After the pause, it was back up to running 4-5 seconds.

Again, never any sputtering, it just shuts off suddenly.

It seems like a fuel problem to me. I wanted to at least get it back up to the garage tonight, so I took off the air cleaner and squirted some starter fluid in there. It didn't stay on, so still something wrong, but I was able to drive it up to the garage by giving it a squirt of starter fluid every couple of seconds.

Now for the weird part: Once it was parked in the garage and stopped, after another squirt or two it just kept running. Ran fine for probably a minute, but as soon as I went to move it forward, it quit. Gave it another squirt, started it back up, let it run, worked fine so I tried to back it up a foot or two. Boom, quit.

Now, a tractor that only runs when it's not moving is pretty worthless... Does anyone have an idea of what would cause this? I would think a blockage in the tank wouldn't make it shut off so suddenly, nor would a clogged fuel line/filter let it run just fine as long as it isn't moving.

Any ideas? Thanks in advance.
 
   #2  

jaxs

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Process of elimination. Until you said it ran with starting fluid,I was almost sure a safty switch or wire was intermitenly making and breaking contact. Will it start now without start fluid? Will it run indefinatly sitting still? Will it run indefinatly at high rpm sitting still? If yes to all check filter or fuel blockage with gas in a small tank w/hose barb,gravity feed carb to see if problem go's away or make's no difference. If it still will not move under it's own power,I would suspect trash restricting float needle or high speed jet.
 
   #3  

Roadworthy

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I have a Kohler on my lawn mower (garden tractor). Frequently it won't start right off and I need to put a small amount of gasoline down the carburetor. That seems to get it running fast enough to make the phony fuel pump work and I'm okay from there. On a hod day mowing it may quit. I think it vapor locks. I've thought about adding an electric fuel pump. There is also a fuel cutoff solenoid int the carburetor itself to prevent run on. You could check there. Suggestions may give you some direction but they're no substitute for troubleshooting your particular problem.
 
   #4  

Username Taken

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I'd take a look at the carb float. Sounds like it might be stuck.

The float lets gas into the float bowl and when it's full, the float shuts it off. Since a lot of floats spend most of their lives in the full position, they can get get stuck there
 
   #5  

ericm979

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Usually when the float sticks it does not shut off the fuel flow and the carb overflows.

This sounds like a low fuel flow problem. The fuel line or filter could be clogged. The carb inlet could be clogged. Or the vent on the tank (often in the cap) could be clogged. If it does not let air in the flow out the bottom slows to a trickle. The easy test is to open the cap and see if it runs better.
 
   #6  

jaxs

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I have a Kohler on my lawn mower (garden tractor). Frequently it won't start right off and I need to put a small amount of gasoline down the carburetor. That seems to get it running fast enough to make the phony fuel pump work and I'm okay from there. On a hod day mowing it may quit. I think it vapor locks. I've thought about adding an electric fuel pump. There is also a fuel cutoff solenoid int the carburetor itself to prevent run on. You could check there. Suggestions may give you some direction but they're no substitute for troubleshooting your particular problem.
🙂 I thought I was the only one old enough to know what that means but you could be right. Great minds think alike.
 
  
  • Thread Starter
#7  
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macindude

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Oct 4, 2014
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Hubertus, WI
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Simplicity Legacy
OK, sounds like my initial thoughts are in the right ballpark. I'm going to take apart the carb and clean it up this weekend as well as replace the fuel filter, and see where that gets me.

There is also a fuel cutoff solenoid int the carburetor itself to prevent run on. You could check there.

That's an interesting idea... I'll take a look at that too. Thanks!
 
   #8  

dirttoys

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Ozarks
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ac 170 bobcat 773 tak 235
OK, this one's a bit weird to me.

I have a late-90s Simplicity Legacy (prior to the XL model) with a Kohler engine. I was working in the yard, driving around a corner when boom, my engine just quit suddenly. It was as if I had shut it off. No sputtering, no nothing.

After looking at it for a couple minutes to make sure there wasn't anything that should have done that, I decided to see if it was a fluke. I was able to start it right back up, but after 5-10 seconds it quit again. Started it a third time, and it lasted maybe 3-4 seconds, a fourth time and it lasted only about a second or two. Let it sit for a bit while I pondered what might cause that, and tried one more time - After the pause, it was back up to running 4-5 seconds.

Again, never any sputtering, it just shuts off suddenly.

It seems like a fuel problem to me. I wanted to at least get it back up to the garage tonight, so I took off the air cleaner and squirted some starter fluid in there. It didn't stay on, so still something wrong, but I was able to drive it up to the garage by giving it a squirt of starter fluid every couple of seconds.

Now for the weird part: Once it was parked in the garage and stopped, after another squirt or two it just kept running. Ran fine for probably a minute, but as soon as I went to move it forward, it quit. Gave it another squirt, started it back up, let it run, worked fine so I tried to back it up a foot or two. Boom, quit.

Now, a tractor that only runs when it's not moving is pretty worthless... Does anyone have an idea of what would cause this? I would think a blockage in the tank wouldn't make it shut off so suddenly, nor would a clogged fuel line/filter let it run just fine as long as it isn't moving.

Any ideas? Thanks in advance.
Maybe stuff floating in the fuel tank? when the fuel is at the correct level and sloshing a bit, blocks pick up.

Quick check is to add fuel and see if problem changes, but, filling it up and having to drain is a drag.

Water can do the same thing when it gets 'deep enough'. Consider cleaning fuel tank.

Best,

ed
 
 
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