Kubota F2560 losing power

[ch1ch2]

The mower is stored outside and covered. I replace the fuel supply rod. I cleaned out the tank and found that the old fuel supply rod was coated with rust. Since I think I have done everything that would be from the fuel tank supply to fuel tank return, for the moment, let's assume that is not the problem. What else could cause this problem? I appreciate everyone's help.

Joe

I am going with fuel also. I had a metal tank that started rusting and I gave up on it and bought a new tank. I have another tractor with a plastic tank. It stopped flowing fuel at times. I took off the tank and could not find anything until I washed it out with a water hose. It took 4 times until stuff stopped coming out.

 

[kuboman]

The mower is stored outside and covered. I replace the fuel supply rod. I cleaned out the tank and found that the old fuel supply rod was coated with rust. Since I think I have done everything that would be from the fuel tank supply to fuel tank return, for the moment, let's assume that is not the problem. What else could cause this problem? I appreciate everyone's help.

Joe

Ok lets assume its not fuel. When it starts to loose power, is there black smoke? Does it regain speed as soon as you let off on the peddle?
We need more specific details. Post a video if you can. It still sounds like fuel to me. But if you can provide more information then you might convince some of us it is something else.

Just an aside, I had a JD diesel mower that would run great for days but then for no reason act like it was starved for fuel. I replaced filters blew out lines replace lines changed pumps but the problem would show up at any time. Finally i got a really bright light and looked in the tank. In the bottom was a handful of pea gravel that would get sucked into the supply line and plug it. No pattern to the problem, just when ever. You may have a object in the tank that is not obvious that can stop the flow of fuel. Just saying!!

 

[JOESCDP]

Fuel tank cap vent may be plugged up. Worth taking a good look at. Next time it shuts down on you after 15 Min, unscrew the cap and listen for air rushing in, and see if it'll start right up again.

I replaced the fuel tank cap and I have taken the cap off when the mower starts to bog down with no improvement. When I vacuumed out the tank I fashioned a 24" wand that I attached to my shop vac. I made an intermediate tank to collect any fuel or debris. The wand was able to go across the bottom of the tank and I got all the fuel that was left after I drained the tank and a bunch of rust flakes. The thing I don't understand is why would the lose power when the HST is engaged? When I ran the mower with the blades engaged it ran fine. What happens when the HST pedal is pushed to make the mower go forward fuel wise? Is there some linkage that is suppose to push more fuel to the engine?

 

[aczlan]

IIRC, there is no HST to throttle linkage (to test, try moving the mower around at idle and see if it throttles up when you start moving.
If you stop moving, does it recover, or does moving "trigger" a case of the engine loading up and shutting off even if you stop moving?

Aaron Z

 

[JOESCDP]

IIRC, there is no HST to throttle linkage (to test, try moving the mower around at idle and see if it throttles up when you start moving.
If you stop moving, does it recover, or does moving "trigger" a case of the engine loading up and shutting off even if you stop moving?

Aaron Z

OK, I am going to shoot a video clip and post it to help along. Everyone has given great suggestions. I am struggling with a little injured back issue and it is raining here in Maryland, so check back in a day or so to view the video. Thanks again.

 

[JOESCDP]

OK, I am going to shoot a video clip and post it to help along. Everyone has given great suggestions. I am struggling with a little injured back issue and it is raining here in Maryland, so check back in a day or so to view the video. Thanks again.

Spoke with a Kubota mechanic today. He said there is a safety switch connected in the HST path, but I am having a hard time finding it.

 

[EastTexFrank]

Spoke with a Kubota mechanic today. He said there is a safety switch connected in the HST path, but I am having a hard time finding it.

I may have an answer for you in a couple of weeks. I know that's not much help. I dropped mine off at the dealer this week for the exact same problem except that mine will almost stall when sitting still. It only has just over 400 hours on it. I did just about everything that you did to try to fix it but nothing worked so I gave up and brought it to the dealer. Let them figure it out. I sure as heck can't.

I will say though that I miss that thing. I'm back to mowing a 4-acre yard with the ol' B2400 and rear mount mower.

 

[JOESCDP]

Spoke with a Kubota mechanic today. He said there is a safety switch connected in the HST path, but I am having a hard time finding it.

The Kubota mechanic also said the problem might be electrical and not fuel related. Replace the controller unit in the steering housing and put in a new battery. Problem reoccurred 24 minutes after starting.

 

[kuboman]

A video of your unit when it is having the problem would be helpful. To eliminate any kind of electrical problem hot wire the fuel solenoid directly to the battery. If that stops the problem then you can assume it is electrical. If not then its fuel related.

 

[IvanS]

I had this exact problem with my F2260. You said you replaced all the fuel lines, I just want to inquire if you truly replaced "all" the lines. In my case I did nearly everything you did before replacing every fuel line. It turns out that the rubber line that crosses over the top of the transmission was collapsing due to heat, heat that is only experienced when you engage the PTO and operate the unit for some time as you described. The combined heat of the HST and PTO operation was the only thing that would cause the issue.

I had the rusted metal pickup line inside the tank as well. Cleaned all, replaced filters, replaced cap.

Once I had replaced all the fuel lines - some were a bugger to get to - the problem was solved. It sounds like you almost experienced the cure after replacing the fuel lines. Are you sure you got all of them? And did you use a high quality hose?

Your machine is likely about the same vintage as mine. I had the problem two years ago with around 500 hours on it. I think it's a matter of the age of the rubber hoses more than anything.