Briggs and Stratton vanguard 20 HP V twin spitting fuel

[Ianv]

A video of the engine running
https://youtube.com/shorts/iYbA8e2mHao?feature=share
Can’t put the filter back on without it stalling, won’t rev out all the way, spits gas out of the carb and Black smoke coming out of the exhaust

 

[ILENGINE]

Sounds like running on one cylinder. possible dropped exhaust push rod or intake valve seat came loose.

 

[hlw49]

Don't think a dropped exhaust valve would cause that since it is not building compression to spit back. It would be rare for an intake seat to come loose since in coming fuel would keep the valve and seat cooler it is usually the exhaust valve seat that comes out. Exhaust push rod out could cause it or even a worn out cam. Pull the valve cover and look see. If the push rods are intact and valves adjusted properly turn the engine over by hand and makes sure the cam is opening the valves like it should.

 

[Ianv]

Don't think a dropped exhaust valve would cause that since it is not building compression to spit back. It would be rare for an intake seat to come loose since in coming fuel would keep the valve and seat cooler it is usually the exhaust valve seat that comes out. Exhaust push rod out could cause it or even a worn out cam. Pull the valve cover and look see. If the push rods are intact and valves adjusted properly turn the engine over by hand and makes sure the cam is opening the valves like it should.

Valves checked out

 

[Scrubcadet10]

Does fuel continue to flow up and out of the carb if you shut it down? Im wondering if you have float/needle issue inside the carb, i have seen them bad enough where they run way too rich.

 

[Ianv]

just cleaned out the carb everything is good still spitting out gas though out of one side

A video
https://youtube.com/shorts/4ZESyPeyAKI?feature=share

 

[slomo]

just cleaned out the carb everything is good still spitting out gas though out of one side

A video
https://youtube.com/shorts/4ZESyPeyAKI?feature=share

You need to pressure test the needle and seat inside the carb. Should hold 7psi for a good while. Looking at it and spraying cleaner does not verify the needle and seat is working proper.

Another thing you could do. Remove the carb WITH fuel line attached. Hold carb at same engine mounted level. See if fuel pours out the engine side of the carb. Guess depending on how you hold it, could come out the air filter side too.

Can also remove the carb. Take a piece of fuel line. Connect it to the carb. Blow into the fuel line. Listen for air leakage inside the carb.

 

[slomo]

I hear a clinking noise. Like a loose valve seat possibly. Pull the head and see what you got.

 

[Ianv]

It’s getting spark but it’s only running on one cylinder

 

[slomo]

It’s getting spark but it’s only running on one cylinder

Where is the spark at exactly? One cylinder has spark and the other doesn't? So one cylinder is running, the other is dead? Both cylinders have spark?