25 hp Kolher, sputters and dies

[besserheimerpha]

I've got a 25hp kolher gas engine in my JD mower/tractor that was giving me fits tonight as I tried to plow. It would be running along fine at full throttle with partial choke, then start to sputter and die. As it started to sputter, sometimes I could save it for an extra minute by closing the choke down to almost shut. It would sit for a couple of minutes and wouldn't restart no matter what I tried to do. After a couple of attempts to start I smelled gas so I let it sit for about 5 minutes while I did some shoveling. I came back and she started right up. This whole process repeated about three times before I got the plowing done. I know the gas is a little suspect, as it's been sitting for a couple of months (I think the last fill up was mid-December; it's been a while between snows). But that doesn't seem to explain why it would start after sitting for a while. My plan is to put new gas in it and probably change the fuel filter, and maybe run some carb cleaner through it. Is there anything else I should try?

Thanks,

John

 

[DieselPower]

I got a used Craftsman garden tractor off of a friend a few years ago that was having similar problems. I had removed the fuel bowl off the bottom of the carb. It has a electronic needle valve assembly in it and it had a bunch of gum and varnish build up on it. I cleaned it out and ran some fuel injection cleaner through it (the kind you add to the gas) and it has run great ever since. Might be worth checking to see if yours is gummed up.

 

[cp1969]

Did it run OK the last time you used it? If so, I'd suspect ice. Drain the gas, fill it with E10.

 

[Hooked_on_HP]

It soud like either the needle and seat are stuck or the fuel filter is pluged. You are on the right track with the filter and carb cleaner.

 

[MossRoad]

I'd check the fuel filter. I have a 25HP Kohler that did similar things last week. It would run at low throttle, but die at high throttle. Wait a while and it would run again and then die. Changed the fuel filter and O.K. Best of luck.

 

[john_bud]

If the fuel is supect, did you put Stabil in last time you used it?

If not, you may want to put in some stabil and carb cleaner. New filters can't hurt and may help. Draining the tank and putting in new fuel with carb cleaner would be best but $$$.

jb

 

[BTDT]

Some folks used to recommend Seafoam. It's a gas additive. I put some in fuel tank on my Snapper with Briggs 12.5hp engine when it started running kind of rough. That stuff cleaned out the inside of my tank for sure. I had to dump carb bowl several times before it finally cleared up and started running right. Your use may vary.

 

[Olmike]

I'd guess that the carb venturi is icing up from what little humidity is in the air. An air cooled engine won't heat the carb enough to keep the the air from freezing in these temps as it passes through the venturi.

 

[Soundguy]

I've had brigs's do that... usually a fuel obstruction.. or a stuck fuel needle/flaot.

Soundguy

 

[sandman2234]

I would bet Hooked on Hp and Soundguy are in the right ballpark with the gummed up needle and seat.
David from jax