Fuel problems

[tsyama]

Aloha all from Hawaii. I have a 04 John Deere L130 with a 23hp Kohler Commander. When not in use the fuel filter is 3/4 full. Starts right up but eventually level goes down to almost nothing then starts to surge until I choke it a little and then will continue to run. Changed fuel filter but still does the same thing. Took apart and cleaned carb, fuel solenoid, float and needle valve. Blew all lines, tank to filter, filter to pump and pump to carb. Also, blew pump with a little air, all clear. Problem still exists. Could it be the pump not pulling gas from the tank? Need some help...please

 

[ILENGINE]

Everybody likes to make an issue of how much fuel is in the fuel filter. Due to how the fuel system is set up with the pump down range of the filter, it causes cavitation in the filter which causes some vaporization leading to an almost empty filter. If the mower keeps running I don't think it would be the fuel pump, but stranger things have happened. I suspect it may be a heat issue, with fuel vaporizing in the carb bowl.

make sure there are no cracks in the fuel line between the tank and the pump which could be sucking air, and opening up when everything gets warm. Also check the pulse line from the pump to the engine for cracks