Briggs and Stratton 18 hp Twin II Flooding out

[ILENGINE]

I was assuming that after the carb repair you installed the air cleaner base plate to the carb. If it is doing the flooding without the air cleaner base plate attached to the carb, then I would look at either the gasket between the two halves of the carb, or the needle valve isn't sealing. also make sure that the float isn't full of gas.

 

[chance123]

also make sure that the float isn't full of gas.

Good point! This has thrown me more times than I can remember

 

[jimswieringa@yahoo.com]

I was assuming that after the carb repair you installed the air cleaner base plate to the carb. If it is doing the flooding without the air cleaner base plate attached to the carb, then I would look at either the gasket between the two halves of the carb, or the needle valve isn't sealing. also make sure that the float isn't full of gas.

I changed gasket between top and bottom of carb and checked float and no gas in it. I changed fuel pump diaphram and gaskets. Drained oil as crank case was full of gas. iIm getting fuel threw hole on top of carb. Looking at engine from front its on choke cable side? I checked needle valve and no groves or damage. I watched video on u tube which is great on how to rebuild this carb and followed instructions and still can't get it to run. I really feel stupid. Thanks for any help. Jim S P.S. I used to live in Mokena and eat at that great steak house on the corner at the center of town.

 

[Rivets]

I'm confused after rereading this entire thread. You say that the model number is 42A707. When I look that engine up it should have a brass float that is adjustable. When you took the carb apart for cleaning, did you replace the float needle and seat? The float needle may look good, but more times than I care to count looks can be very decieving. I would replace the needle and seat with this kit #394682. I have included a service manual for your engine which may help you.

http://dl.dropboxusercontent.com/u/12502267/B&S Service Manuals/02_271172TwinCylinderLHead.pdf

 

[Coca Kohler]

Has your needle valve been jammed open.

 

[DaveTN]

I know how "Misery Loves Company" and I'll chime in with a similar problem with a 17.5 Single Cylinder Kohler on a Craftsman rider that would do the same thing. Last week I wound up putting a fuel line shut off valve on it so the owner could keep it from flooding out after it sat for a while. I checked the float and needle operation and worked fine, but let it sit overnight or a few days and it would flood the cylinder as well as above the bowl, into the carburetor throat, and up into the filter. I could see a puddle of fuel with the air filter off! I drained a teacup of gas when I removed the carburetor bowl. About that much blown out of the cylinder when I took the soaked plug out! Also blew out about a 1/4 teacup of gas out of the muffler! Now it decided to go to the extreme opposite and not get any fuel at all once the shut off valve was turned on! We'll have to put a carburetor kit in it as it just won't cooperate and hope for the best. It too has a plastic "Non-Adjustable" float. Doesn't give a guy any room to adjust anything out. These non-adjustable plastic floats are aggravating when a little adjustment on the float level would clear things up. Looks like you have a "Problem Child Mower" on your hands!

 

[Bobby1]

I have a MTD Yard Machine with a Briggs and Stratton 18 hp Twin oppose cylinder Model 42A707.

I have rebuilt carberator with new jets, needle valve, and cleaned. The problem is that it floods out as soon as I try to turn it over. Gas shoots out over the top of the top of carberator and dumping a lot of fuel down the intake.

I can start it cold with the throttle wide open but as soon as I try to back it down it quits, floods out.

I have called a lawn mower/small engine expert in the area and he doesn't have a clue. Does anyone know something I can try. It's got to be something simple I would think and I'm just not getting it. :confused2:
Thanks for any help, The Duckster

Did you get this fixed??

 

[Tinkerer200]

So are you telling me that this cannot run without the air cleaner? I have never seen any gas engine that can't run without the air cleaner, this would be the first and I'm 66. I really appreciate your input. Let me know, thanks.

That is not at all what he is telling you ALTHOUGH, B&S says the filter needs to be on for this engine to run correctly. I have never concerned myself about whether it was on or not.

I do not see where you said it runs the same with and without the air filter. Listen to these gentlemen, they are trying to help you. As a youngster you have a lot to learn. I am 84 and still learning.

Since this engine relieves some compression when starting via the Intake Valves, it does naturally blow some out the carb but not to the extent you are experiencing.

Walt Conner

 

[Wild Wild Wes]

I have a MTD Yard Machine with a Briggs and Stratton 18 hp Twin oppose cylinder Model 42A707.

I have rebuilt carberator with new jets, needle valve, and cleaned. The problem is that it floods out as soon as I try to turn it over. Gas shoots out over the top of the top of carberator and dumping a lot of fuel down the intake.

I can start it cold with the throttle wide open but as soon as I try to back it down it quits, floods out.

I have called a lawn mower/small engine expert in the area and he doesn't have a clue. Does anyone know something I can try. It's got to be something simple I would think and I'm just not getting it. :confused2:
Thanks for any help, The Duckster

I know it's late but it might help someone else out water in the fuel weak fuel watered down

 

[1madmouse]

Did this ever get solved? I have a splitter doing the same thing

I know it's late but it might help someone else out water in the fuel weak fuel watered down

.