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Les

Please help me out, this carb is driving me nuts!

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JeffNemes
STOP! ********* DON'T RUN the engine with diluted oil. That's the best advice I can give you. I don't know if your machine has a fuel pump, but if it does it may have a hole in the diaphram. If so, that will permit raw fuel to pumped directly into the crankcase while still being punped to the carb. If not, most likely you have a problem with fuel getting past the carb needle valve. Anything is possible, your rings could be worn where they permit raw gas to pass into the crankcase while at the same time not permitting oil to pass the other way into the combustion chamber to produce smoke, but that sounds far-fetched to me. A fuel shut off valve will prevent fuel from overflowing the carb and leaking past the rings into the crankcase while the engine is off. That exact thing happened to me, and a shut off valve solved the problem. Heat can build up pressure in a fuel tank. After using the machine, do you hear pressure escaping when opening the fuel fill when everything is hot? I hope others, with more experience than I, can give you better suggestions before your engine is destroyed.

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Al
Hi, The problem may be the nozzle above the main jet. there is a flange that looks like the face on an engine valve. This seals to the carb casting. If it leaks the gas runs from the float bowl into the intake of the carb. The float valve will keep letting it in as long as this lets it run out. There is a possible fix if this is the problem. Take an old nozzle and sand [NO BRASS OR ALUMINUM ON A GRINDING WHEEL, PLUGS THEM UP AND RUINS THEM] the threads off the nozzle then using some fine valve lapping compound or agressive tooth paste, lap the seat using this modified nozzle. Next get a new nozzle and I will get a part number for a kit that has some small teflon washers that will slip over the nozzle and hopefully seal it. IF this is what is leaking, you have nothing to lose as you will need a new carb casting to fix it otherwise. Just be sure this is the problem first. If your float valve pressure tests OK This is a likely suspect. Good luck, Al

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Sandy_Lake_Imp
You will need to determine if this is happening while sitting or while running. Let it drip into a pan overnight.If while sitting it is still the float or float valve or other internal carb problem. If it only does it while running it has to be coming past the rings-check the choke control for full return.

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Al
Hi, Forgot to mention don't use a screwdriver to remove the nozzle unless you hollow grind the blade so the faces where it contacts the slots in the nozzle are parallel, Then grind the sides of the blade so it is the same diameter as the shaft, no flare out. Briggs makes a 4 way Jet wrench for this and they are relatively inexpensive. The taper on the screwdriver and the tend to spread the slots in the nozzle and cause it to bind in the threads and the blade must go to the outside edge of the slot. The taper on the average screwdirver gets in the threads and ruins the carb bowl assy, Over the years I have probably had 25 carb bowls brought in with the threads jamed up and the nozzle stuck in them due to trying to remove the nozzle with a screwdriver. This is beyond fixing, new pieces only. Good luck, Al

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Les
My B-210 has the Briggs 243431 10 hp motor. I had it rebuilt, bored & new rings in 1994. This year it started getting gas in the oil. I tried rebuilding the carb myself, no luck. I took the carb to a shop and had them rebuild it and put in a new seat, still got gas. I took it back to the shop, they said that they re did it and tested it with a gas tank in the shop for two days. Oil still gushes out when I check oil. One suggesstion was that gas was getting by the rings, but if that were true, then I would see blue smoke, wouldn't I. Any advice would be appreciated. Thanks.

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