Ok guys, I've got a 6800 that has been giving me problems for quite some time now. Wasn't serviced for quite a while before I got to it. Changed all filters and fluids. Also began running lucas fuel additive in because seemed to have dirty fuel and wanted to clean the system. Once It got bad enough I decided to remove injectors and have them cleaned, guy told me there was a black syrup looking substance in them but now they look brand new. Installed them and after bleeding system it fired right up and fuel knock seemed to go away and ran great. Few days later someone was driving it and it just died. After I bled lines again and attempted to prime it, I finally got it running but was dumping black smoke. Pulled delivery valve section out to have cleaned and checked. Guy said it was relatively clean, thanks to fuel additive I'm assuming, but 2 valves were turned, so he fixed it up and I installed it. Now it won't start on its own.
m6800 won't start
- Thread starter kmoeller
- Start date
I can manually slide the governor connecting rod and it will start but idles all the way up and dies unless I keep holding the governor back. Also seems that the throttle lever and foot pedal have no effect on it, meaning, it doesn't throttle up or down. I have removed the back section of injection pump and everything thing seems in good working order, but obviously I am missing something.
Assuming silence means no one else knows whats wrong either. Guess I'll keep trying to figure out the issue on my own and post with the solution.
That black syrup thing gives me pause. Have you cleaned out the fuel tank? Could whatever causes the syrup still be in the tank. Seems logical since it ran well for a time. You might pull an injector and see if it's fouled again.
"Syrup" was probably due to poor fuel and not changing the fuel filters for a very long time, and its spent its life in a sandy environment. Has nice clean fuel coming out now. I am 90% positive my issue is with the governor in some form or fashion.
You may end up having the injector pump rebuilt. Plugged fuel system probably wasn't limited to just injectors. I'm sure it has trash from one end to the other. Running fuel treatment has started it's job but the gunk it breaks loose has to go somewhere. May have even stopped up the injectors again.
That tractor is pretty basic. If it has fuel and air it should run. Follow the fuel system down the line. Could be as simple as bad fuel line. I always like to start with the simple stuff first and go from there. Keep us posted.
That tractor is pretty basic. If it has fuel and air it should run. Follow the fuel system down the line. Could be as simple as bad fuel line. I always like to start with the simple stuff first and go from there. Keep us posted.
RCW
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BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
I'm only swinging at fences - don't know your tractor at all. Given it ran good for a while, not sure I would suspect governor just yet.
But, if spent so much time in sandy conditions, lack of service...any chance tank bunged up like rentthis suggested, or maybe fuel lines from and returns back to tank?
Sometimes it takes some time running for the junk to clog things up - then it's all stop....
Also, someone recently said something about a screen at the top of a water separator on an MX(?) getting plugged causing fuel starvation....
Maybe just track good fuel flow between tank and IP?
I tried to attach a schematic of separator from:
http://www.kubota.com/part/partsList.aspx
But it didn't work - I'm not smart enough!.
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I would rig up a portable fuel tank with a rubber hose like an outboard motor tank with a primer pump in the hose. Put a cheap in line fuel filter in the line and connect it to your injection pump. Put the tank some height above the engine so gravity will siphon fuel from the high tank once you get it primed using the bulb in the hose.
If it will start and run OK then you know the problem is in the tank, lift pump and filters. If it does not start then you know the injection pump at the very least is one of the problems.
If you don't have access to a boat tank, any tank can work if you get a basic electric fuel pump to send the fuel to the injection pump..You are trying to supply brand new fuel through a new delivery system to the injection pump bypassing many fuel system components which may or may not be bad.
To find a solution you need to narrow down where to focus your efforts and it sounds like you have not been able to do that with confidence.
Dave M7040
If it will start and run OK then you know the problem is in the tank, lift pump and filters. If it does not start then you know the injection pump at the very least is one of the problems.
If you don't have access to a boat tank, any tank can work if you get a basic electric fuel pump to send the fuel to the injection pump..You are trying to supply brand new fuel through a new delivery system to the injection pump bypassing many fuel system components which may or may not be bad.
To find a solution you need to narrow down where to focus your efforts and it sounds like you have not been able to do that with confidence.
Dave M7040
I have narrowed down the problem to within the governor housing. I have had the delivery valve section of the pump rebuilt. I also had the guy who rebuilt that and the injectors come take a look at it and eve he is stumped but we do know something is wrong within the governor housing. As I said earlier, I can get it to run by manually controlling the fuel rack.
My rebuild guy and some "Kubota Master", believe that the start spring is hooked up in the wrong spot and that the fuel shut off solenoid is bad. I find that hard to believe because I tried starting with the shut off solenoid in and also watched the solenoid with it out and it was working. As far as the spring location, I don't believe that either because I have pictures from the manual that show where its supposed to be hooked up.
Has anyone ever rebuilt the delivery valve section of one of these pumps? I'm wondering if maybe he did something wrong to cause the fuel rack to not slide as freely as it should, therefore the spring isn't enough to pull it back.
Has anyone ever rebuilt the delivery valve section of one of these pumps? I'm wondering if maybe he did something wrong to cause the fuel rack to not slide as freely as it should, therefore the spring isn't enough to pull it back.
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Yes it's possible that the delivery valves have a part swapped or not installed right.
It's also possible that he didn't time the delivery valves properly to the rack.
And yes I would match the springs exactly how the manual has them set of it will not start of if it does it could run away if they set it to full throttle.
With no delivery lines hooked up the injection pump should put out a small fountain of fuel (amount varies) usually 1" to 3" high or more.
If any one or more of the fountains are not to the same level as the others there is an issue, if there is no fountains or very week then something is completely wrong.
Well guys, I got it figured out. I had noticed that the fuel rack would only move freely when the governor connecting rod was no attached, and as soon as I put it on the stud and put the hold down nut and spring on it was kinda tough to move. After giving it some thought, I decided to loosen the nut as much as I could in order to get it to move freely. It started up great and I could throttle it up and down as normal. I assumed that meant there was supposed to be some sort of washer behind there to allow it to not bottom out on the housing, however couldn't find any mention of a washer in the parts manual. SO what I did is put a washer on the stud, then the connecting rod and then hooked the spring to the stud and then put some lock tite on the nut and threaded it on as much as I could without over tightening it. All seems good now. For future reference, that nut is a "lock nut" but as we all know, once you use one over and over that "locking feature" fades away. Sure I could've gone to town to get a new nut but my Kubota dealer sucks and chose lock tite instead. Hope this helps someone in the future. Thanks for all the input.