145a runs for a while (20 min) then starts to quit.

[tomplum]

They are a PITA . You could try blowing back through the fuel line behind the fuel filter with the cap off and a clean rag on it to see if that improves the situation. It is more likely that plant debris has started to clog the line. If you get more mileage so to speak, you know what has to happen.

 

[02chuck1]

Took the beast out to mow the lawn, figured I would run it till it died and check for vacuum on the tank. When it died I jumped off and opened the fuel tank and did not hear any escaping air.
When the engine was trying to quit I looked at the fuel filter to be sure it had plenty of fuel in it. I think I will replace the fuel cap, just because and pull the carb off again and see if there is anything in there I might have missed. I noticed that one time when it was trying to die and I pushed the choke on it ran really well for a short bit. That sort of leads me to think there might be something in the one of the carb passage ways. I figure the choke pulls fuel from different spots.
Any ideas excepted as usual.
I did manage to dick around with it enough to finish the lawn

Thanks
Chuck

 

[rayikeo2]

Chuck, Put that new cap on before you mow any more. Here is what happens when the vent hole is plugged. The fuel pump draws the gas from the tank and the vacuum starts to form, the more gas used while mowing causes the vacuum to increase continuously. The longer you mow the stronger the vacuum gets. All this time the fuel pump is straining harder and harder the pump the gas. Finally it can't mechanically do it and the carb is starved for gas and the mower actually runs out of gas no matter how much gas is still in the tank. Now when the engine quits running the vacuum in the tank actually sucks the gas out of the fuel line and returns it into the tank. When you take the cap off the vacuum is released but there is no fuel in the carburetor so it doesn't restart until you run the starter long enough to re-prime the gas line and carb. You put the cap back on and the whole process starts again. Note: The fuller the tank the quicker the vacuum occurs. A nearly empty tank takes longer to create the vacuum because of more air in the tank. All this time you are running the engine with a vacuum the fuel pump is straining to overcome it and the diaphragm in the fuel pump stretches out of shape and it eventually ruptures. I am betting this is your problem and to save more damage to the fuel pump you need that new cap on before you mow any more. Post the results after you replace the cap so we will know if it fixes the problem.