Seems to be runing out of fuel

[dobey]

I have a 77 ezgo 2 stroke cart. It starts right up, runs for a few minutes then just quits and runs on the starter. When I turn it off and let it sit for a few minutes it starts right back up and does it again.

At first I thought it was getting hot but I just replaced the plug and fuel filter with a clear plastic one and I can see now that it is running out of gas, stalling and when I get off and lift the seat I can slowly see the filter fill back up.

I was next thinking the tank was building a vacuum and checked the vent hole in the cap (fine) and even tested it with the cap off but it still does it.

The lines seam fine, no cracks that I can see, and blowing and sucking on the line from the pump to the tank is easy and gets bubbles blowing and gas sucking. I pulled the pump and cleaned it all up, the diaphragms are fine and I cant blow through it backwards, when there is gas in the line it pumps enough to get a bit out the overflow line on the carb.

Sorry for the long post I am just trying to be really descriptive, I cant figure this one out and it is driving me crazy. I had about a 1/4 tank of fuel and even thought maybe it was low, and the bumps were sloshing it enough to get air in the line so I filled it to half tank with the same results.

I guess I am hoping someone here had a similar problem and can say 'It is just this stupid' before I go in for the full tear down.

[kc1ez]

I had the same problem and it was the valve in the carb that opens and closes with the movment of the float, it had a small burr on the black rubber needle that caused it to stick even when the float droped

[ezwrks97]

I would agree, think you need a carb rebuild. usually a pretty easy job. "best o luck".

[dobey]

I got some clear fuel line on it to see what was happening and this is what I found out.

There was allot of air in the line (maybe 50% air) and the pump seemed to be having trouble pulling more fuel. I hooked up the line from tank to pump, and then put a long piece of clear line on the exiting side of the pump and sucked fuel through the system till all the air was gone. I noticed that it would very slowly go back the wrong way and I am assuming the little clear plastic disks the pump uses for check valves are whipped and just not sealing tight, making it hard to pump fuel if there is allot of air.

Once I got all the air out it stayed out, and is now working fine.