19 horse Briggs & Stratton will only run with choke half on

[TobyU]

When you say it runs okay or fine with two fingers over the carburetor hole, does it rev up and go to normal full speed of around 3,400 RPMs or do you have to keep the RPMs much lower even with your fingers to get it to run?
If it will go up to its normal operating speed above 32 to 3400 when you're giving it extra choke from your fingers, then you either have a massive air intake leak or the carburetor is not flowing enough fuel.

New doesn't mean good or right..
I never replace carburetors as I would much rather keep the original one and just clean it out.
You will either have a Nikki or a walbro carb and most likely a Nikki.

These things only have one main jet but on the Nick you it can fall out but if that happened it would be laying in the bowl and it'll be running excessively rich.

 

[JimP2014]

Generally speaking I can offer you this advice I bought a new carburetor installed it and for 6 weeks I was troubleshooting problems that really didn't exist meaning after 6 weeks I purchased another carburetor I installed it not a problem in the world with the engine. I did purchase a completely different product in other words after 6 weeks I did not buy another one of the same thing I haven't had a problem with it since zero adjustment after install.

Jim

 

[JimP2014]

Generally speaking I can offer you this advice I bought a new carburetor installed it and for 6 weeks I was troubleshooting problems that really didn't exist meaning after 6 weeks I purchased another carburetor I installed it not a problem in the world with the engine. I did purchase a completely different product in other words after 6 weeks I did not buy another one of the same thing I haven't had a problem with it since zero adjustment after install.

Jim

Carbhub 594605 Carburetor for 594605 792768 591734 594603 Single Cylinder Engine Replacement Carburetor - 594605 Carburetor

That's the carburetor I bought that eventually worked perfectly my engine is a 19.5 horsepower single OHV engine now whether that's the spec for yours or not I don't know but in my case it's strange cuz there was no fuel air mixture screw to adjust but there was nothing to adjust it was unbelievable how it ran Right from the get-go. But you could do the Nikki wall bro thing if you choose to.

Jim

 

[rhkraft]

Probably a small crack in the plastic fuel line and it sucks air. The crack could be in the fuel tank. I had one that ran good with a full tank and went to hell when the fuel level dropped enough to expose the crack and suck air.

 

[slomo]

OP checked out on us.

Did you get this running?