18HP B&S opposed will only run on full choke

skyflier22

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Hi, I have a 18HP briggs twin II on a Craftsman yt3000. I am unsure of the exact model but it has a 3 screw carb. I bought the mower for a hundred bucks, and it ran terrible the and it was pouring a lot of fuel out of the main jet in the carb so I bought a carb rebuild kit and cleaned the whole carb and replaced all the gaskets. It ran much better, It will run nearly perfect at full choke but when you push in the choke it will surge at full throttle and a low throttle it will die :mad: I have cleaned the carb three times and it still will only run on full choke. I don't have any air leaks and I have good spark and spark plugs.

PS: I do mower repair an the side so I am fairly knowledgeable on them but this is stumping me:confused2::confused2::mad::mad::mad:
 

RDA.Lawns

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Dose this mower have a fuel pump?
 

Pumper54

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If you slowly take the choke off does the engine RPM increase and then drop? It almost sounds like you have an intake leak and need the choke to reduce the airflow to the point the air fuel mixture is correct. Double check your carb and manifold mounting to insure they are tight and have the proper gaskets in place.
Tom
 

skyflier22

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If you slowly take the choke off does the engine RPM increase and then drop? It almost sounds like you have an intake leak and need the choke to reduce the airflow to the point the air fuel mixture is correct. Double check your carb and manifold mounting to insure they are tight and have the proper gaskets in place.
Tom

I will check on Monday but I am almost positive I don't have a air leak.
 

Tinkerer200

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Check your thread on other forum.

Walt Conner
 
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