I have a Briggs & Stratton 5HP Engine (Horizontal shaft) And it has the diaphragm carb on it. The last person to own it messed with the carb adjustments and it'll have trouble starting and idling sometimes. I was wondering how to adjust the screw on this type. For example, do I turn it out like 2 1/2 turns and adjust from there or what? I can't find repair info in my manuals for some reason. I've adjusted hundreds of carbs but just don't know it's specs. the model number is 135212 and the type number is 0140 01 code number is 93031127. it's mounted on a MTD chipper. And also the carb might need rebuilt which is why the person was attempting to adjust. I just want to get it all right before I tinker with it.

Water being heavier than gasoline is likely to be in the carburetor. If a bowl type carburetor, remove the bowl and clean. Allow the fuel to run for a few seconds to clear the water from the lines.
If a diaphragm type carburetor, remove the diaphragms and allow the fuel to clean the lines.

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My money is on a partial blockage of the main jet or the passageway to it. You're having to force it to run through the idle jet by fully choking the incoming air. There's not enough gas coming in with the choke open to allow it to run.

I'm thiniking total carb disassembly, carb cleaner and an air compressor combined with a ton of patience will take care of the issue.

Could be that the needle is stuck in carb, or else the fuel pump diaphragm is bad. Check the pump, thats what I would check first.

acid dip rebuild carb make sure fuel selinoid on bottom of carb moves freely

you have a gloged carb try takeing it off and blowing out the carb with a compressor
take the bowl apart its on the bottom of the carb you will find a float and needle seet
blow all of that clear and make sure the fuel line is clear

hope this helps you
bob

There is a solonoid valve in the carburator that shuts off fuel to meet emissions standards. Be sure it is wired to be powered when key is in run position. You can hear a "click" at the carb. when the solonoid powers up.

Your Briggs & Stratton Classic engine uses a diaphragm to pump fuel. Yours has deformed and needs to be replaced. It is a very easy repair. Remove the air filter. There is a bolt on the end of the fuel tank nearest the spark plug. Remove this bolt. There is another bolt just behind the carburetor that holds the tank to the engine. Remove this bolt also. Now you should be able to gently pull the tank away from the engine. After the carb clears the intake tube, you can tilt the tank enough to remove the governor linkage from the carb butterfly shaft. Now the tank/carb assembly is loose and in your hand. Go to the workbench. There are 5 screws that hold the carb to the tank. Remove these 5 screws. When you lift the carb from the tank, you will see the diaphragm gaskets. Remove the old and install the new set. The 2 part diaphragm set consists of a rubber diaphragm and a paper gasket. The rubber part goes against the tank, then the paper gasket, then the carb. Leave the screws in the carb as you reinstall it, and the screw tips will align all parts during reassembly.
The diaphragm set is readily available at any Briggs parts dealer or online. Make sure you take the Model, Type, & Code numbers with you when you go for parts. These numbers are stamped into the metal fan shroud just above the spark plug.
Good luck!

if its a vertical shaft as in the shaft points down,its a 6 sided bolt nexr to the shaft/if its a horizontal shaft its right at the base just above where it bolts to the machine usually below the oil fill cap

an easy way to know that is to start engine and give it a shot of starting fluid ,if you can keep it running by this method I would replace diaphragm.

Try cleaning the air filter, and check fuel tank for any debris.
Replace fuel filter if there is, and give the fueltank a good cleanout.
Use fresh fuel to refill.