M8540 loosing power

[McDonaldFarms]

Have a M8540 that started loosing power and running rough when under a load. Drained the water separator and cleaned it and changed the fuel filter. Bled the system still doing the same thing. Can watch fuel level fluctuate in the separator glass. Talked to dealer and suggested drain the tank. Did that still having same problem. If we let tractor sit overnight separator bowl fills back up with fuel and tractor cranks right up and runs good for about 5 minutes and then same problem reoccurs. Manual mentions checking tightness of the fuel coupler bolt but does not say or show where it is. Checked with dealer and they don’t know where it is. Any help with where bolt is or experience with this problem would be greatly appreciated.

 

[rentthis]

I have had problems with that style Kubota fuel water separator. The fittings where the hoses connect to the separator get loose and suck air. I have ,in the past, had to replace several. I diagnosed that problem by plumbing the separator out of the system and running it for a while.

 

[Tx Jim]

Welcome to OTT
Several yrs back I had similar fuel issue with my M4900. Local Kubota dealer service manager advised me to check for clogged screen in water seperater housing fuel shut off valve. I located screen ,cleaned it & fuel starvation problem ceased. YMMV,Jim

 

[lugbolt]

Check the fuel tank vent.

Check the lines for restriction.

Check the separator inlet/outlets for black stuff in the hose connection.