Briggs Vanguard 6.5 hp only runs with choke on

The bowl bolt on most small 4 cycle carbs has 2 passages - vertical and horizontal. Run a thin wire (phone jack wire) thru them and spray with carb cleaner. Make sure the jet above this bolt is clean, too.

Yeah, hard to clean the passages on that bolt! You have a fuel restriction in some passage or jet, having to choke to run. There must be a tube that dips into bowl for fuel pickup - make sure it's clean and flows. Also, get your engine # and find a carb part # - there may be an AM carb for cheap. I've rebuilt these carbs with a kit and never got engine running correctly - ended up buying AM carb. Now, chances of a good rebuild increase if you have a parts washer with carb cleaner.

A good carb cleaning should do the trick. Stabil is a fuel stabilizer. It doesnt help with the ethanol issues. Unless stabil has come out with something new. I use startron and have been using it for 7 or 8 years and have not had any ethanol relate problems with any of my stuff

Your jet(s) are plugged. Can of carb cleaner, air compressor, and maybe a thin wire and blast out all passages you can find from bottom and top.

On some carbs that bowl bolt screws into a tube that has ports through it higher up in the carb. Make sure those are clean and the jet that goes out the top of that tube is clean. Be careful spraying carb cleaner, don't ask how I know.

Sounds like you have a fuel blockage somewhere. I would get some ethanol gas, or make some yourself by adding 10% heet to a tank and try running that through the system. Ethanol is excellent at dissolving varnish and all the other crud the dead dinosaurs leave behind. Though if the carb is 100% plugged, then it likely needs a mechanical cleaning and re-build.

When I had this issue it was chunks of rust getting through the fuel filter gumming things up. You are on the right track. Its definitely a fueling issue. Speaking of which I guess I'd make sure you have free flowing fuel to the carb as well.

Get some Seafoam.

I used to have to take apart & clean one small engine carb or another a couple times a year - between the stuff that sits all winter & the stuff that sits all summer. Now I try running a tank or part tank of gas with Seafoam added to it first - and it's been a while since I've had a carb apart. I have a Stihl weedwhacker that I always had to have a bit of choke on to use (given to me by an in-law, sat for a couple years) - one treated tank and it works like a top. Just a month ago noticed my JD LA135 with Briggs twin in it was running rough after sitting the winter. I did the Seafoam thing & it's running like new again after one lawn mowing session - and also stopped the smoke-puff-on-startup thing it's been doing for a couple years now.

Magic juice.

(Still a chance you'll have to disassemble, if it's a piece of real dirt - but most times it's gas gum)

EDIT: Looks like some green in your float bowl - a sign of possible gas gum in a jet.

A/M carbs are cheap. I got one for my Honda powered log splitter for $20.00 off ebay. Quicker to replace then dick around trying to clean every little port out after disassembly. I have done it that way and had success, but for $20,00 and the ease, the new carb was the way I decided to go last round.

Pouring some magic juice in the tank is even easier. I always try that first.

I find seafoam works well but have you checked the gas tank vent sometimes it's the smallest
of things that give trouble.

If you have to run it choked the carb probably needs cleaning. Like the folks say, it's easy to do. Compressed air makes the job easier yet.

Had this issue with an older Briggs opposed twin some years ago, a garden tractor freebie. Just the ticket for hauling rounds out of the woodlot. Pulled the carb apart and sprayed with cleaner then blew it out with air. Been running like new ever since.

It was an orphan, had set abandoned for lord knows how long. When I got it going I installed a shutoff valve in the fuel line. If it's gonna set for longer than a few weeks, shut off the fuel and run the carb dry.

Clean the carb.Then seafoam in every time you fill your gas can.The new ethanol fuel only has a shelf life of a couple months.So don,t store a lot of fuel.Fresh is best.

Reminds me... I need to put a little time on my splitter today.

Ya, if it's a piece of solid dirt like a rust speck or grain of sand or whatever, getting physical with it will be needed. We also have a 2" water pump here with a 5hp Briggs on it, and there is a piece of steel in the internal tank structure that is rusty and will bung a carb jet up with a rust spec once in a while. Intended to get a new tank for it for a while now but just hasn't happened yet.

But for the gunky varnishy spoogey type stuff that happens when gas deteriorates, Seafoam kicks butt.