I have a Kubota B-21. It is a 3 cylinder diesel. It only has 127 hours on it. I was in the woods cutting old trees and wanted to bring the logs out. So I started the Kubota, let it warm up for about 10 minutes, then drove into the woods. I left it idle while I was loading the bucket. All of a sudden it died. It will not even turn over. The lights work. The battery is new. The fuel filter is clean. I don't have a wiring drawing or any idea where to start. Does anybody have any experience with these things? Any help would be appreciated. Where it is I can't even drag it out, so I have to fix it there.

 

Sounds like you lost electrical power. Can you get it to crank on the starter by jumping the terminals on the starter solenoid? If you can, then run a wire from battery pos. terminal to the fuel shut off terminal on the injector pump and it should start.

 

Thanks for the reply. I tried the starter. I jumped the 2 big terminals and it sounded like it was spinning but not engaged with the flywheel. Would the fuel shut off stop it from turning over? Is there only one wire to the valve? Or is it obvious which one is hot?

When I turn the key on all the lights work and it looks like the glow plug light will work. Where would the lose of power come from? Between the switch and fuel shut off?

 

Since that uses a starter-moutned solenoid, you need to jumper it from the battery terminal to the small starter terminal to get that to engage. Turn the key to "on", jump the solenoid, and it should fire right up. If not, check the fusebox for an "ign" fuse, it's probably blown, or one of the plugs for the engine harness has come loose. Those little 3cyls vibrate a lot when idling, which will work electrical stuff loose and damage fuses, lights, etc.

 

It does shake a bit. The fuses must be under the dash somewhere. I never looked for them before this. I will look in the morning. Thanks.

 

All the fuses in the little panel are good. The panel is in the engine compartment. Except none of them have anything to do with running. I found one inline fuse at the starter which was also good. I jumped the starter and it works, but still not starting. I looked at the plug on the pump. It has 2 red wires going into the plug. Can there be 2 hot wires to it. I didn't want to try and jump it without knowing a little more. I can't get the dash off because I added a windshield and it is down tight to the dash. I have to pull it off but it is raining right now. So later I will pull it and look around a bit more.

 

Normally the fuel shutoff solenoid would only have one hot wire going to it and it would be grounded through the pump.
However thanks to Ford_Six you now have the starter running.
The wire to the FSS should be hot when the key is at on (run) and when the key is at start. The light gauge wire at the starter solenoid should be hot when the key is at start. It would seem that neither is happening. I think I would try to see the wiring at the ign switch.

 

I had a similar situation happen to my John Deere 4310. I'm not too familiar with Kubotas as I have breathed Deeres my whole life, but does your B-21 have a seat that will kill the engine if you get off of it when the PTO is engaged? My Deere died on me once when I got off of it and I couldn't get it to re-start for the life of me. Turns out I hit the PTO switch on my way off of the tractor and caused it to kill itself. Might be an easy fix if thats what it is. If not, these guys have you pointed in the correct direction with the igntion.

 

Good call Deere's built 20+ years ago wouldn't let you start then if the PTO is engaged so I am sure all the new ones do that by now no matter the brand.

 

Thats the only thing I can think of because it took me about a 1/2 hour to figure it out when it happened to me. Sometimes its the simple things that are the hardest to fix.

 

It could be worse, you could have a modern tractor:
(the good part starts about 3:20)
YouTube - Top Gear - Tractor Challenge part 1

I actually had to operate a tractor to run an earth auger when my boss couldn't figure out how to make it work. 2008 JD, he could start it but couldn't move it or engage the PTO.

 

Update. I checked the PTO cut off and the pedal cutoff too. They were not the problem. I went to the dealer and asked for advice so I could get it out of the woods. He said to pull the solenoid off the fuel pump. There are 2 hot wires to it. The ground is through the pump. One wire is supposed to activate the solenoid at starting and the other is supposed to hold it open. Here is what I don't understand even though it worked. There is a pin sticking out that pulls in when the key is in the start position. Then it is held in by the other hot wire when the key is in the run position. The dealer told me to pull the solenoid off and put something in the hole to push the little flapper in. When I did that it started right up. I moved it to a better location. I held the solenoid against a ground and turned the key on, and the little pin pulled in like they said. But that is opposite of pushing something into the hole to make it start. I put it all back together and it is starting yesterday and today. I didn't replace anything or fix anything that I know of, but it is running, so I shouldn't complain. I just hope it does not happen again.

Thanks for all the input, I appreciate it.

 

Sounds like you fixed it to me! Atleast now you know where to start if it happens again.