You might check to see if you're getting enough fuel. Maybe the the fuel line has broken down internally and is restricting flow or something in the fuel tank restricting the flow out the tank.

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I second the fuel line check, Over time the fuel line swells and reduces fuel flow. Time for new ones.

 

Thanks I will try tomorrow

 

I figured I'd throw this into the mix as it wasn't mentioned. There may be an inline filter or possibly a built in screen in the gas tank just where the gas exits that has been covered with sediment not letting gas through. Another thing, there's no mention on what gas your trying to use but if it's old, don't expect much out of it since stale gas is basically whatever hasn't evaporated and what's left is shellac.

 

Does it have a automatic choke? Sounds just like a problem I fixed recently on a B&S lawnmower engine. Started, ran for a few seconds, sputtered and then died. Replaced the automatic choke, located between the exhaust and head, made the adjustments in the instruction sheet and the engine ran like a champ. If it doesn't have a auto choke, you might have a clogged up vent on your gas cap? Did it run again for about 5 min after you removed the gas cap and added more gas? Try running it with the gas cap lose, about 1/2 to 3/4 tank of gas. If it runs without stalling after 5 min you found the problem

 

You say the carb was a bit dirty. Did you remove the bowl and possibly the carb bowl not oriented back in the right spot limiting the float from dropping /not allowing enough gas passed the needle valve seat

 

Try loosing the gas hen it dies and restart it. The cap vent may be plugged.

 

I have had a few Briggs like yours where the bowl nut passages were blocked with dried gas and needed a GOOD cleaning.


https://outdoorpowerinfo.com/repairs/briggs_walbro_lms_carb.asp

 

Try the gas cap. If the cap vent is clogged, then a vacuum will be created, preventing fuel from getting to the carb.

 

i concur with gas cap, run without cap to test.
else a dirty or out of adjustment carb, to test put choke on to about 1/3 to 1/2 to see if it will stay running.
if that worked carb is running too lean so its either dirty (lots of small holes to clean, not much needed to plug them up) or fuel air mix needs to be adjusted.
or float bowl/needle valve not working correctly which if it cant keep up with fuel burning then bowl will run dry

 

I did drain the tank and put in fresh gas, carb had just a very very small amount of sediment, and it has a manual choke When you hear it starting to die, I have tried turn the choke on and it still dies, even if i try pushing the primer bulb. I will check to make sure it is getting enough fuel through the fuel line and bowl is not stuck closed.. Thanks everyone for you help

 

run without gas cap to test.

 

Vinny, I tried that too

 

when this happens to me i try everything that has been mentioned.

you already put in good gas so next thing is fuel delivery.

remove bowl , turn gas on and see if it flows. lift float up to see if it stops ( could be flooding out )
check choke function.

i also take the time to remove air box on a Honda , remove idle jet and spray carb cleaner/compressed air in all passages that can get to.

replace bowl back on correctly. excellent point that if on wrong would restrict float.

this usually takes care of 90% of the problems assuming you have proper gas flow. without gas flow then you have clogged/ bad fuel line or filter. sometimes i'll blow air or carb spray with straw up fuel line from carb and into carb from there. that has solved this problem in a couple cases.

please report back.

 

Just be careful with that air gun blowing out the various orifices. Not sure what you have there but the rubber seat for the needle valve can fly out of there without you ever knowing,, ask me how I know this and then you'll have a new issue on top of what you already don't know.