Got a new carb on my 2pg but running super rich

[tomj]

The original carb started leaking in my 2 stroke robin 80's ezgo, so I replaced it with one on ebay and its running horribly rich, takes a long time to start, smells like gas when it finally does and loads up for the first 50' of driving. The screw on the side has no effect. Everything I've read said that is the only adjustment. Is that true? It runs great just before it runs out of fuel...

[newtjl]

I have adjusted that horizontal screw nearest the engine with some degree of success. The base setting on it is run it all the way in to a soft seat, then out 1 1/2 turns and adjust from there. To see if the screw is making any difference, just run it all the way in to a soft seat and see if will start at all. These Chinese carbs arent very precisely machined and tend to run a bit rich out of the box if they run at all, at least in my experience. It will probably never run as well as it might with an OEM carb but you should be able to get it adjusted well enough that you are satisfied with it. One other quick note and this may not make a bit of difference in the world but I did notice that none of your hoses are clamped off. I have seen at least one occasion in which air was getting into the fuel system at a hose connection. I hope you get it lined out.

[cart around]

Look at posts 51, and 52 of this thread. https://www.buggiesgonewild.com/show...80#post1730380

You will want a spring like that on the throttle cable to prevent backfiring, and get a smooth throttle response.

What part was leaking? You may want to repair the original with parts from the new one.

Pages J-6, J-7, and J-8 will tell you exactly how to adjust your carburetor.

[tomj]

I swapped the float needle from the newer carb to the old one and put the old carb back on. The problem is just as bad as before, The carb is just getting totally flooded with fuel to the point where it is puddling in the corregated intake hose with the older carb like it was coming out thru the overflow hose in the newer carb. (the older carb does not have an overflow hose) Is there some sort of pressure regulation on the fuel pump? Because if there is and it is allowing unregulated pressurized fuel to overcome the float needle that would explain the problem...

[cart around]

Fuel going the wrong way, and pooling in the intake hose would have me checking the reed valves.

You should have suction, but no blowing.

[tomj]

I pulled the carb and reed cage and the reeds were fine, then I went to remove the fuel pump and it was a little loose to the engine case to the point where there might have been a leak of crankcase pressure/vacuum. I opened up the (mikuni diaphragm type) fuel pump and although it looked fine inside I'm not sure of how the diaphragms are supposed to feel- they are made of a transparent plastic (sort of a thin flexible version of the stuff used for plastic clamshell packaging) rather than fabric reinforced rubber like I'm used to seeing and sort of oil-can when flexed rather than flex smoothly like a softer rubber would, which has caused problems for me in string trimmer carb diaphragms in the past. In any case I reassembled everything and the first test run was OK but I need to try it again cold to be sure.