Agility 125 Starting / Running Problems

[mt_100]

My Agility 125, 7300km is having an issue.

Starts fine when the tank is full, and runs great. However once it gets below 1/2 a tank it has a hard time starting, just cranks. Eventually it will start however it will die when I brake to stop.

Filling with gas fixes the problem however it returns again as the tank gets low.

Any ideas on the problem?

[Lammy1000]

Your fuel filter is clogged.  When the tank is full more head pressure is available to push the fuel through the partially cllogged filter.  How many miles, where do you live and is the fule quality known to be bad?

[mt_100]

I had checked it and disconnected the line from it, cranked it, and a good stream of fuel came out. Not a trickle.

I live in W Michigan. Not sure if the fuel is known to be bad, just overpriced.

[kymcomandan]

I just put a new clear fuel line on my scooter today. Is there any way you can put a clear fuel line on yours, run the gas past half way empty so there's just a few inches of fuel in the bottom of the tank & check through the clear fuel line to see if you're getting fuel to the carb when it's running or cranking? If you can see fuel getting to the carb through the clear line then it's probably carb related with maybe some junk in the bowl or jets. But if there's no visible fuel flow to the carb through the clear line when it's cranking or running then you have a blockage somehwere between the tank & the carb that could be in the bottom of the tank or the fuel filter, regardless of whether it flows without back pressure or not. Because the carb creates back pressure at the entry to the carburetor by what's called the needle & seat. Your flow test without back pressure is subjective & not a reliable test compared to while the scooter is running or cranking.

[kymcomandan]

I'm not a hundred percent sure about the name of the needle & seat. In any case there is a valve at the entry to the carb that is controlled by the floats that creates slight backpressure when everything is assembled & working properly. So checking your fuel flow without the carb being attaches is different than when everything is assembled & cranking or running.