Briggs&Stratton running problem...

I have a Craftsman 4n1 yard vacuum with a B&S engine#123k02-0240-e1. Ran great last year. Took it out of the shed, checked the oil(replaced last fall) good, added gas(ran stabble last fall till it ran out), cleaned spark plug regaped to .030, cleaned air filter with air comp. Started right up let choke run till it was warm then took choke off. Ran for another minute and died. Started up again full choke, then no choke and started to die put back at full choke started up again then died. Took carb off let everything soak in cleaner for 48hrs. Took wire to all holes made sure nothing was clogged. Then spray carb cleaner to all holes. Air comp. all holes too make sure no clogs. Emptyed gas container checked hose (no fuel fliter) cleaned with air and tank also. Re-assm check float to see if gas is steady (YES). Start up same issues. Changed the plug. Start up same issues. If I play with the govener lever it will catch and not stall. Also if I leave choke on it will all most die but doesn't. Took off the cover looked at the govener arm looks fine. Bought a carb kit but the only thing I did not replace was the needle seat gasket. I used powerequipmentinfo.com too make sure I re-assm everything correct. Any other things I should look at or try?

I feel your pain, have had similar problem with other small engines. Think I took the carb off my tiller 6 times before giving up and replacing it... Sometimes a carb just can't be fixed and has to be replaced. But if you don't want to do that, you have to do the complete teardown, including the welch plugs, and replace anything with the slightest evidence of corrosion.

Gasoline nowadays goes bad very quickly, especially the winter formulations, and the ethanol seems to attract moisture. Carbs often have two or three different metals in them (brass, aluminum, steel) which means corrosion happens quickly if moisture gets in. Even without that, the wax or varnish from ageing gasoline will mess up the tiny little openings enough to cause running problems like yours.

(I am now reminded to go drain the gas out of all my small engines and run a little oil into the cylinders!)

Change the seat - had a Koehler 10hp die the same thing - now it runs like new

Took the carb off 2 days ago and it has been soaking since then. I am going to re-assm tomorrow and hope for the best. Thanks for the responses.

Just replacing parts and soaking won't always do the trick. You need to make sure all the passageways through the body of the carb are clear with compressed air. It's the only way to make sure it's all clear.

Mini Motors said:

Just replacing parts and soaking won't always do the trick. You need to make sure all the passageways through the body of the carb are clear with compressed air. It's the only way to make sure it's all clear.

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Even that won't always do the trick, if there has been any corrosion or if the gas has been in there long enough to deposit varnish inside where you can't get the compressed air (behind the welch plugs). I had two carbs like that - no amount of soaking, compressed air, cleaning with welding-tip reamers, etc. could get the engine to run smoothly. Sometimes replacing the carb is the way to go.

So after cleaning it again and replacing the welch plug and needle seat gasket it is running great. It was raining yesterday and today so this weekend will be the real test. Thanks for all the responses.