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i'm new and posted this already under new member intro. so in case that limits the viewing i will post here too.

mower started on first pull and ran great all summer, sat 1 week and won't start or run on its own but will on carb spray. i removed carb, disassembled, cleaned with carb spray and compressed air, verified needle and seat open when float is down, closes when at top of its travel. fuel is supplied as verified by fuel running out of plastic bowl when fuel hose is removed. no fuel squirts when i prime it, seems like it would run if i could get it primed. please help.
 

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Has to be in the fuel delivery system. My thought is the float is stuck when on the machine. Can you take the bowl off when the carb is on the mower and verify the gas is flowing? Might be a bit of a clog in the inlet on the carb. Good Luck, Steve, and welcome to the site.
 

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yes i removed bowl and it was full of fuel, needle valve closed. i depressed float, opening needle valve and fuel drained back out of inlet. once again i cleaned carb bowl and inlet with compressed air, no restrictions in inlet, float does not stick, fuel is entering carb.

i am not satisfied that the plastic primer flange surface is mating completely with the carb gasket, the plastic flange surface is slightly misshapen, likely not enough to be a problem. but even if i get past the priming issue and use carb spray for initial shot of fuel, engine will not run after carb spray is consumed. i have worked on hundreds of auto carbs over the years in my auto repair business and cannot see where or how this simple carb can be at fault, but it must be. admittedly i am not a small engine mech so i don't claim to have any answers, just a lot of questions.

my business is not prospering right now or i would already have gambled and replaced carb. plus i hate to admit defeat by this simple little contraption. any further suggestions?
 

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You might consider removing the primer bulb off and check the mechanical operation behind it. Could be a check valve not functioning. And I know what you mean about not letting a small piece of machinery getting the best of you. Good Luck!
 

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yes i removed bowl and it was full of fuel, needle valve closed. i depressed float, opening needle valve and fuel drained back out of inlet. once again i cleaned carb bowl and inlet with compressed air, no restrictions in inlet, float does not stick, fuel is entering carb.

i am not satisfied that the plastic primer flange surface is mating completely with the carb gasket, the plastic flange surface is slightly misshapen, likely not enough to be a problem. but even if i get past the priming issue and use carb spray for initial shot of fuel, engine will not run after carb spray is consumed. i have worked on hundreds of auto carbs over the years in my auto repair business and cannot see where or how this simple carb can be at fault, but it must be. admittedly i am not a small engine mech so i don't claim to have any answers, just a lot of questions.

Three things.
1. On the leg that goes down into the fuel bowl, there is a very small hole in the side of it. Make sure that is open. If not, use a very tiny wire to poke it clean, then use carb clean and air to blow it out.

2. There are also I believe a couple of holes in the main jet nut (holds the fuel bowl to the carb). Make sure those are open and clean.

3. Lastly in the center of the fuel leg, there is a plastic tube (Main Jet),make sure it is clean and open

4. Check out this site and book mark it. It is a great site that you will use often. www.outdoorpowerinfo.com and scroll down to small engine repairs. You will find all the carbs and how to tear them down.
 

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Could be a crack or hole in the primer bulb allowing it to suck air instead of fuel. Especially if it is keeping fuel in the bowl. Or maybe the main jet clogged. When you push the primer bulb and there is no fuel makes me suspect the priming system. Good luck!!
 
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