New 5hp briggs randomly dies

redneckracing674

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ive got a 5hp briggs flathead, brand new, no governer. it has a tendency to die at idle, regardless of how hard ive been on the throttle. it isnt idling too low, and has a fairly new diaphragm, and i havent touched the carb, or the tuning. it has no idle mix adjuster, so i cant crank it rich, but light choke doesnt make a difference. it has a pulsa jet carb, but behaves nothing like my 3.5hp briggs, that dies after wot if its too lean. it did this after it ran low on fuel, but it didnt run out, and after filling it full, it self healed, for a short time. now it does this regardless of fuel level. im running fresh biden gas. it idles right below the clutch engage point. please help...
 

Chainlube

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ive got a 5hp briggs flathead, brand new, no governer. it has a tendency to die at idle, regardless of how hard ive been on the throttle. it isnt idling too low, and has a fairly new diaphragm, and i havent touched the carb, or the tuning. it has no idle mix adjuster, so i cant crank it rich, but light choke doesnt make a difference. it has a pulsa jet carb, but behaves nothing like my 3.5hp briggs, that dies after wot if its too lean. it did this after it ran low on fuel, but it didnt run out, and after filling it full, it self healed, for a short time. now it does this regardless of fuel level. im running fresh biden gas. it idles right below the clutch engage point. please help...
Sounds like you got something floating around in the float bowl, drain the bowl and see if that helps.
 

Chainlube

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i did have the carb off the tank at one point, because i was gonna use a smaller one, but i think it was clean.
Oh sorry, you have one of those carbs, I kinda forgot about those. Is the tank clear, there could be something small floating around in there and gets stuck to the pick up tube.
 

darwin

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5hp briggs with a pumper carb? Any pics of said motor?
 

darwin

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Can't magnify your pic very much. From what I can see it looks like a complicated carb for a small motor, lots of different pieces/bodies. Those have a strainer on the pickup tube. Is it dying because of low idle? Is there a mixture screw hat's hidden behind a brass plug? Are you using fresh gas? From my experience that diaphragm might have a slight slit in it. It's hard to tell/see but same symptoms on a couple of mowers in the past. Diaphragm can't pump enough gas at low idle to keep it going, maybe.
 
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