new to forum.. problem with carb?

[outlander800r]

im not sure exactly what this mower is.. i know its a 17 horse ohv brigs... this thing just dumps gas out the carb/aircleaner.. and almost seems like it wont let it turn over?? there is a electrical plug on the bowl? of this carb.. which i have never seen somthing like that before... if anyone has had a problem like this i would appriciate some help.. thanks

 

[Rivets]

Sounds to me like the needle is not shutting off the fuel in the carb. Would you do a couple of things and then get back to us. We need a better picture of what is happening. First, pull the dipstick and see if fuel has mixed with the oil in the crankcase. If yes DO NOT ATTEMPT TO START. You will have to drain this out, but not till we fix the cause. If there is an oil/gas mixture in the crankcase pull the spark plug out. You will probably have oil in the cylinder which we will get out later. Second, please give us the model and serial numbers off the engine. This way we will know what we are talking about. (Some of us like me only guess, but we try.) Third, how good of a mechanic are you? This will tell us whether to send you to a repair shop, or try to explain the repairs through this site. Sometimes it is easier and cheaper to have someone else fix it. Waiting to hear back.

 

[DaveTN]

Sounds to me like the needle is not shutting off the fuel in the carb. Would you do a couple of things and then get back to us. We need a better picture of what is happening. First, pull the dipstick and see if fuel has mixed with the oil in the crankcase. If yes DO NOT ATTEMPT TO START. You will have to drain this out, but not till we fix the cause. If there is an oil/gas mixture in the crankcase pull the spark plug out. You will probably have oil in the cylinder which we will get out later. Second, please give us the model and serial numbers off the engine. This way we will know what we are talking about. (Some of us like me only guess, but we try.) Third, how good of a mechanic are you? This will tell us whether to send you to a repair shop, or try to explain the repairs through this site. Sometimes it is easier and cheaper to have someone else fix it. Waiting to hear back.

Could be the float has gas in it, making it ride heavy and not let the needle shut off gas flow. That would let gas flood the carburetor and down into the engine. Or like the other mechanic said...some foreign material under the needle and seat not letting it close properly. Would have to take the float out to shake it and see if it's full of gas.

 

[DaveTN]

I have seen a connecting rod get bent when liquid gasoline gets into the combustion chamber. The valves close and liquids do NOT compress, so something will give. With a lot of resistance, I take the plug out and crank it over. Usually gas will come spewing out like a geyser! I've only seen a few bent rods over that sort of thing, but Hey!..ONE is too many eh?

 

[ILENGINE]

DO NOT AND I REPEAT DO NOT CRANK THE ENGINE AND LET THE GAS SPRAY OUT. I used to do it that way a few years ago until I had one were the carb leaks and I pulled the spark plug out, disconnected from the wire, and in my hand with the plug wire sitting about 4 inches from the engine. Got on the seat, while holding the disconnected spark plug in my hand. The first crank sprayed gas, the second crank sprayed more gas, this is going all over the mower, and on my wooden board trailer. Third crank lit it. Spraying gas causes static electricity which can arc and ignite. If I wasn't carrying a fire extinquisher I would have lost the mower and my trailer.

Always use an air hose to blow out the gas from the cylinder, and I repeat to no crank the engine to expel the gas from the cylinder.

 

[Rivets]

Sorry, I should have pointed that out earlier. I've had the something happen. Thanks IL for reminding all of us about that.

 

[Agoat70]

I sounds like you have somewhat of the same problem with your craftsman riding mower. I have a 1996 model #917217532, 42" cut, riding mower. It too has a couple of wires going into the bottom of the fuel bowl of the carburator. My problem is that the thing starts just fine, runs for about 20 min, then it acts as if the choke is on. The engine loads up, smokes, looses power and dies out, and then you cant start it until it cools off. The oil level isn't getting higher & it doesn't really smell like the fuel is washing past the rings. Jumped over all the shut off switches to see if maybe 1 of them was the problem. Same thing happened, ran 20 min & died. Reconnected all shut offs after cleaning all contacts. I'm at a total loss. Anybody else have any ideas?

 

[DaveTN]

DO NOT AND I REPEAT DO NOT CRANK THE ENGINE AND LET THE GAS SPRAY OUT. I used to do it that way a few years ago until I had one were the carb leaks and I pulled the spark plug out, disconnected from the wire, and in my hand with the plug wire sitting about 4 inches from the engine. Got on the seat, while holding the disconnected spark plug in my hand. The first crank sprayed gas, the second crank sprayed more gas, this is going all over the mower, and on my wooden board trailer. Third crank lit it. Spraying gas causes static electricity which can arc and ignite. If I wasn't carrying a fire extinquisher I would have lost the mower and my trailer.

Always use an air hose to blow out the gas from the cylinder, and I repeat to no crank the engine to expel the gas from the cylinder.

Thanks for the heads up! I've had weedeaters lite off when pulling them over and checking for spark. Like you, I've done this for years and got by with it, but it only takes ONE time to cause an accident. It's the fine mist that ignites, not the liquid. That's why you got by with the first two spurts. dp

 

[DaveTN]

On second thought... DO NOT CRANK THE ENGINE OVER WITH GAS IN THE CYLINDER AND SPARK PLUG OUT. Like IL says, it could ignite!

 

[wildbill]

Make sure the gas cap is vented. This happens a lot, the cap vent gets plugged and the fuel flow is restricted to the carb. Just loosen the cap and run the mower. Make sure the tank is no more than 1/2 full, loosen the cap by at least one turn, put a piece of duct tape on one side from the cap to the tank to keep it from vibrating off, and let 'er rip. If it keeps running with the cap loose, bingo.

Check also to make sure you have a good flow through the fuel filter if you have one.

Pull the float bowl off and check for trash and build-up.

The wires going to the solenoid on the bottom of the carb is an anti-backfire thing. They sometimes cause trouble and if so will prevent gas from flowing through the main jet when the ign switch is turned off. I do not believe this is your problem.