Does the spring loaded screw on the carburetor bowl on the 15hp liquid cooled engine adjust the float level?

If your motorcycle's fuel system is not functioning properly, it can prevent the engine from starting or cause it to run poorly. One issue that can cause these problems is a faulty float in the carburetor.
The float in a carburetor is a small device that helps regulate the fuel level in the carburetor bowl. It is attached to a needle valve that controls the flow of fuel into the bowl, and floats on top of the fuel in the bowl. When the fuel level in the bowl rises, the float rises with it and closes the needle valve, which stops the flow of fuel into the bowl. When the fuel level in the bowl drops, the float lowers and opens the needle valve, which allows more fuel to flow into the bowl.
If the float in your carburetor is not functioning properly, it can cause the fuel level in the bowl to become too high or too low. If the fuel level is too high, it can cause the engine to flood or stall. If the fuel level is too low, it can cause the engine to run lean, which can cause it to run poorly or not start at all.
If you suspect that the float in your carburetor is not functioning properly, you may need to remove the carburetor and inspect or replace the float. It is always best to consult a service manual or a professional mechanic for specific instructions on how to do this.

there will be a plug at the side top of the fuel bowl that you remove to check and adjust the float level while running
the float level is adjusted by the bolt at the top of the cover above the needle and seat adjust until the fuel is level with the threads of the plug
screw that mixture screw/s in all the way then back out 1 1/2 turns
start the engine and adjust the idle speed by the screw on the accelerator lever
set to around 800 rpms
adjust the mixture screw in until the rpms start to slow
now screw the mixture out until the rpms again slow
mixture adjustment is achieved by turning the screw back in 1/2 the turns that you used to turn it out from the slow in position to the slow position out
again adjust the engine rpms by the accelerator screw to the 800 rpms
most engines idle between 700 and 850 rpms unless and efi engine which have around 850 -950 rpms range

- Now days some carburetors are produced which are fixed and no adjustment is provided.The float is made up of whole plastic like material.
Some floats have the copper/metal notch for the adjustment of fuel level.
- Take the carburetor assembly out.
- Remove the fuel bowls.
- Place the carburetor assembly with the floats upward towards yourself.
- Float level gauge and active data list (taken from the workshop manual) is required to carry out the adjustment. But you can simply adjust the float level correctly without any gauge.
- Hold the carburetor assembly at your eye level in such a way that the carburetor No. 1 is in front of you. Behind is No. 2 carburetor, then behind is No. 3 and then the No. 4. Or we can say that the carburetor No. 1 hides the carburetors 2, 3, and 4.
- Examine carefully the floats of all the individual carburetors be parallel to the surface of the carburetor where the float bowl face is seated and tightened.
- Adjust the float level by bending the float notch towards the needle valve (to decrease the float level and to raise the float) or away from the needle valve to increase the float level (to lower the float).

if the carburetor keeps flooding out, the float could be stuck in the up position. tap lightly on & around fuel reservoir to free. depending on age of carburetor, you might need to put in a carburetor kit.

Why did you need to clean the carb? Routine servicing of the aircleaner would keep the carb clean for life. The pilot screw should be 1.5 turns out approx. with a small adjustment either way. Idle speed is set to a smooth low idle.If this doesn't fix it have you got something in the carb not replaced correctly? The float needle/float assy? How did you clean it? Have you introduced fluff/dirt into the carb and did you blow it clean with an airline?

pour large amounts of liquid carb cleaner into the gas tank
Let it run for a couple of minutes then shut it off and let it sit for a couple of days.

Correct that there are no adjustments, but try cleaning the carb jets first, as many times a small amount of debris in the fuel can cause a performance problem. A replacement carb will be close to $200, and NO carbs will be adjustable. A gasket kit is available if you need. Contact your local Briggs dealer to procure the part.

Try cleaning the jets first.
Fuel Starvation - Float Bowl Carburetor
1) remove air filter assembly
*be cautious of tearing the mounting gasket. If it does tear, you HAVE to replace it. It is part of the priming system
2) remove the float bowl fastener. This is the main jet
3) carefully remove the float bowl, the rubber o-ring/gasket will not be able to be used if it is removed, you WILL have to replace it
4) using a spray 'carb cleaner'
spray up thru the center of the carburetor
spray and clean the main jet with cleaner and 'tag' wire
(tag wire is very thin, and can be used to clean the hole in the center of the main jet)
5) clean any debris from inside the bowl or carb body
6) re-install bowl and center bolt, air filter assembly

*if you need gaskets, your Briggs dealer can supply. The kit is cheaper than individual gaskets, and all the parts needed to finish the above repair are in the kit.


I’m happy to assist further over the phone at https://www.6ya.com/expert/rolandw_c013176d62ee17ae

What's most likely happened is some foreign debris (dirt, rust, fuel varnish, etc.) has gotten stuck on the float valve seat. The first thing you should try is draining the fuel from each float bowl. Turn the fuel petcock off, then loosen the drain screw on the bottom of each float bowl and let the gasoline drain out (catch it in a clean container, if you can, so that you can see what's come out).
Usually, this is enough to clean out whatever is hanging up the float valves. Also, locate the fuel strainer, usually located in a bowl on the bottom of the petcock, and clean it. Installing an in-line fuel filter might help, too.
If this fails to improve the situation, then your next step would be to remove the carburetors and take the float bowls off. Plan on replacing each float valve and, while you're in there, take each float and shake it next to your ear, listening for any signs of liquid inside. Replace any float that has taken on fluid.
Finally, check the float levels. Basically you want the float arms to be parallel with the float bowl gasket surface, just as the little metal 'tang' makes contact - but does not depress, the spring loaded plunger on the end of the float valve. Carefully bend the tang to adjust the float level.

For the corrosion in the fuel tank get a liquid tank liner. It lines the fuel tank walls then hardens to seal the tank from rust. Google “ kreem fuel tank liner “ or go to www.http://www.4secondsflat.com/Fuel_Tank_Sealer.html

For the hard starting, clean the carburetors. (unfamiliar with your bike, I assume it has carburetors and not fuel injection).
ALWAYS have a fire extinguisher on hand when working on carburetors.
Remove the water trap bowl at the bottom of the petcock, (gas valve). Is there any water or trash in the bowl? Drain a cup of gas from the tank. Is there any water or trash in the cup? Dump it, clean it and re-mount it, ( not all bikes have a water trap bowl ).

Drain the carburetors. There should be a screw on the lower side or bottom of the CARB float bowls. Remove the drain screw then replace it after the fuel drains. Turn the gas back on and wait a minute for the carbs to fill with gas. Install new stock NGK spark plugs and try to start the engine. If the bike doesn't start and run properly then shut off the gas and remove the carburetor from the engine.

FOR EACH CARB > Remove the float bowl and clean the entire CARB with a spray CARB cleaner from the auto parts store. Wear protective goggles to avoid getting spray in your eyes. Spray into all the little airways and fittings in the CARB. Remove the idle screw and the air screw on the outside throat of the CARB and spray into the screw holes as well.
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Be sure to put these two screws back in the same hole they came out of. IMPORTANT > do not tighten these two adjusters down. Only screw these in until they LIGHTLY seat. Now turn each adjuster one and one half turns outward. Put the rest of the CARB back together, clean the air filter and install the CARB. Let the float bowl fill then start the engine. This process should get you back on the road.

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