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Discussion Starter #1 (Edited)
I purchased a new cork float for my Lawn Boy 10301 (V-engine with black plastic carb). The old float is swollen. The new float's arm is not bent when compared to the existing one which is slightly bent.

Having never adjusted a float before, I am a little confused. LB's site says 7/16" adjustment. I assume that this is with the needle, seat and cork installed with the carb upside down. In this position, would you measure from the body flange to the highest part of the cork? In this case, the new one is 7/16" and the old one is 1/2". The tells me that the older float shuts off the fuel inlet sooner than the new float will.

I am hoping that a new float will solve my low speed surge problem. (Maybe this is causing a lean mixture which is the reason for the surge at low speed?)

I don't know the history of the machine. (Free Craigslist special!)

Thank you for you suggestions.

Doug
 

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Discussion Starter #3
GREAT. I will check the photos out!
 

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Make sure there is no plastic washer under the seat, whether you installed it or someone else did. They were intended for use on some model F carbs. Just the seat in the carb body, new needle, new float, minus the bowl gasket. Take your 7/16 measurement at both sides of the float where you have access(towards the front of the float). If all else is good in the system, this should have you set in terms of carbureation. Not a bad idea to replace the carb flange gasket as well.
 

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I never needed to adjust a new float. Like Echoman says though make sure it doesen't have the little plastic washer under the seat.

Neal
 

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The book says 15/32" from float to carb body. Generally when inverted, the float should be parallel with the carb body gasket surface but they are pretty forgiving especially in the old LBs that had carb adjustment anyway.

Walt Conner
 

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Discussion Starter #8
I installed the new cork float today. The mower ran well but it would only run in one speed after it warmed up. I looked closer and the appeared that the air vane was stuck. I removed the carb and cleaned the air vane shaft and oiled. I again installed the carb and it varied in speed for the first few minutes. After the motor heated up, the air vane again would not move. I removed the carb AGAIN and swapped the guts with a spare V motor carb. I reinstalled the carb and it ran good. It appears that the body from the original carb was out of shape. I will use the mower in a few days for the true 1 hour lawn cut test.

The photos reflect the original swollen cork float and the replacement float. I didn't bend the arm on the replacement float. It appears to be 1/16 shy of the specs.
 

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You should have no problems with that setting. If it was too high, the needle wouldn't seat, and the carb would flood. Hit a "trouble spot" with the V engine on my Toro the other week. Brought the float down a bit, was good to go. The spec from Lawn Boy as it reads from their manual is "7/16-15/32". You are right at 15/32 it appears.
 

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My 10323 float when set to specs made it about parallel with the carb flange; that might be a good rule of thumb to go by, I dont know. Are all floats created equal?
Created equal to do the same job, but not all are set to the same height spec. They need to be real close to spec-too far off either way will give issues. Either flooding or lack of fuel.
 

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You should have no problems with that setting. If it was too high, the needle wouldn't seat, and the carb would flood. Hit a "trouble spot" with the V engine on my Toro the other week. Brought the float down a bit, was good to go. The spec from Lawn Boy as it reads from their manual is "7/16-15/32". You are right at 15/32 it appears.
I know, this is an old thread but I found it. Not sure what 'too high' means. To cause flooding I assume it means too high in carb when carb in running position ie too low when in the inverted position. So if spec is 7/16 then too high is 5/16? if measured from carb body to edge of float when inverted.
 

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In the photos above, the original float looks good. You can test a float by putting it in a bowl of gasoline and see if it floats! The "bad" floats I have encountered have all been shriveled up, not bloated. The float is coated with some sort of "varnish" that keeps them fuel-tight.
 
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