Lawn Boy Running Rough

12 years ago

My 7 year old Lawn Boy runs for about 3 minutes fine and then starts running rough and eventually conks out. What do you think the problem is? Gotta mow the lawn, the grass is getting high.

Thanks.

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Comments (10)

tomplum
12 years ago
Seeing as though Lb had many different engine choices, model #s would help.
orangedotfever
12 years ago
Sounds like fuel starvation but we need a model number or engine series.
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AAJ_1623
Original Author
12 years ago
The LB is a 4 cycle, 195 CC engine.
thanks
1saxman
12 years ago
Tecumseh. Needs a metering orifice cleaning job. I don't think I can bring myself to type it out for the nth time.
Okay, I'll start. Tilt the mower up on it's right side wheels (carb high). Take the brass bolt out of the bottom of the fuel bowl and don't disturb the bowl - it should just stay on. Clean the holes in the bolt; center hole and cross hole - these are the easy ones. Now take a wire tie like found on a loaf of bread and strip the paper off - straighten the wire and use it to rod out the tiny bleed near the end of the threads that is on an angle. It might look like just a speck of dirt - it's that small. This is the one that does the trick. Put the bolt back in and you should be good. From now on, use a fuel stabilizer and either Seafoam or Marvel mystery Oil in your mower gas can, and you won't be doing this every year.
AAJ_1623
Original Author
12 years ago
You directions were very good- I did as you suggested- took my time cleaning the bolt. Put it back in but the same symptoms. Ran for a minute then started to sputter and eventually conked out. Should bolt be soaked in something? Just seems like the mower is starved for fuel.
orangedotfever
12 years ago
Try running with the fuel cap loose to see if it's a venting problem. Could be the float sticking too.
AAJ_1623
Original Author
12 years ago
Made good progress! Removed the bowl and cleaned it out good and cleaned the float. Ran it 20 minutes with gas cap loose with no issues. Tightened the gas cap and two minutes later started to sputter. Took cap off and ran it another ten minutes fine. Then tightened cap again and ran fine for another ten minutes as I finished up lawn. How do you fix the venting issue (Besides keeping gas cap loose)?
Thanks to all for your expertise! I'm sure this is a common issue.
ewalk
12 years ago
Is the cap not vented via a man made rubber or plastic liner with a red needle valve which allow air in but seals against gasoline leakage outwards . Perhaps Orange can give further direction .
tomplum
12 years ago
The correct repair would be to replace the cap. Sometimes a well placed 1/32" hole in the threads of the cap will allow the cap to vent. Not knowing what you have here, it is hard to know what version cap you have and if it is a style that is meant to vent through the threads.
orangedotfever
12 years ago
I'm not familiar with the 4 cycle Lawnboys but will assume that is has some kind of liner in the cap with vent hole. Try to clean this hole or carefully drill it out with a small drill bit. Buying a new cap is an option if you can't fix it or end up damaging it.

Can you give us a model number?

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Lawn Boy Running Rough

Comments (10)

tomplum

orangedotfever

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AAJ_1623
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Lawn Boy Running Rough

Comments (10)

tomplum

orangedotfever

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AAJ_1623Original Author

1saxman

AAJ_1623Original Author

orangedotfever

AAJ_1623Original Author

ewalk

tomplum

orangedotfever

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AAJ_1623
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AAJ_1623
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