Hello, OK, I have a 21" 2-cycle push Lawn Boy, probably a 1990 's model. Actually the model number is, 10424, SR.# 9902213.

I have taken good care of this unit, but recently after running the mower for 10 minutes it sputters, and dies. I pump the primer bulb a few times and it starts, but after a minute or so it does it again.

I figured WATER IN THE FUEL, so dumped the fuel in the mower tank, dumped all the fuel in my filler can, and added NEW fuel, not any fuel I had, but direct from the station pump into my container. I also stuck a clean rag in the tank, and with a long screw driver probed for any fuel left in the mower's tank.

I added new fuel, and all seemed well, but after cutting for 15 or so minutes it died again. If it sits for a few seconds, and is primed, well it will start, but won't run for more that 30 seconds.

Any suggestions will be most welcomed, THANK YOU..........

Dale in Indy

 

could be running to hot. wrong fuel mix OR.
try taking out your air filter. maybe after it warms its not getting enough air flow

 

Check the fuel tank vent on the cap. Make sure it is venting.

 

Thanks, but NO DICE......

Not the air filter, not the cap, ran it without filter, and cap, and after approx. 3 minutes of cutting, it just sputters then dies. If I hit the primer bulb as it is dying, it will fire for a few seconds, then won't fire up again until it sits for a few minutes.

I will start all over with new fuel, and mixed at 32-1 and see, but I have been mixing fuel for this and all my Sthil equipment for years and no issues.

I also changed the spark plug tonight, it was very wet, NOT SURE IF THAT IS NORMAL OR NOT????

Sure seems like water in the fuel, is there a float bowl that could have some water in the bottom?

Thanks,

Dale in Indy

 

Yes, the float bowl could hold some water but in that case it wouldn't run at all if water was there. You may have a stuck float needle or a fuel line collapsing. Good luck.

 

Thanks, I will look into your suggestions.

Dale in Indy

 

I think I found the problem..................., I removed the fuel line where it enters the carb, some fuel drained out, some evaporated on the concrete floor but a spot didn't, so I suspect WATER was in the carb.

I ran it for 15 plus minutes, and it didn't quit, so I will cut the grass tomorrow, and know for sure.

Keeping my fingers crossed, hehehe.

Dale in Indy

 

YEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA, I hope that will fix it. Good Luck.

 

Well, still an issue. Today it ran approx. 15-20 minutes, seems to start sputtering when pushing the unit UP A HILL, it sputters, then 10 seconds it dies, and if you wait a minute and hit the primer bul it starts, runs a minuted, then quits. Each time it runs a short time period.

I am going to try new fuel once again, starting to think it is heat related.

I will keep you posted.

Dale in Indy

I don't give up easy.

 

Please check the Float in the Carburetor.

 

Have you checked actual fuel flow from the tank?