M9000 Fuel Issue/Loosing Power

[dvcochran]

I think this same problem started last year with my M9. I thought I had gotten bad fuel because the tractor would run normally then loose power almost stalling then run normally again for a few minutes. I drained the tanks (did not remove them), removed the crossover tube and inspected. I tested the fuel pump which seemed to pump strong in a bucket. Replaced the fuel filter and separator filter and added fuel from another source. The tractor ran fine last cutting of last year and all winter. The tractor (1200 hours) ran strong all first cutting and baling this year. Saturday, I had the bush hog hooked up and it started doing the same thing again. I limped it back to the shop and left it. I used it this morning moving hay for about an hour and it did fine. Then it started stalling worse than ever and I barely got back to the barn.
There is fuel in the separator and it is clean as a whistle. I blew air through both of the vent tubes. When I blow through the right side tube (injection pump side of tractor) fuel/mist blows out the other vent tube. I looked at the hand pump on top of the filter housing and it is pushed all the way in and will not move. I do not recall this from the last repairs. I have been looking at the fuel system diagram on the Kubota website but nothing seems obviously wrong.

I honestly don't know where to start. I am hoping some of the folks on here can lend me a hand.

 

[SidecarFlip]

If the system is pressurized the pump knob will not move. Far as the rest goes, don't have a clue. I have to ask however, when it peters out and dies, is the plastic sediment bowl full of fuel or is it empty or nearly empty?

 

[dvcochran]

It is near full, about 2/3rds.

 

[SidecarFlip]

It is near full, about 2/3rds.

It should be full to the top. You are sucking air somewhere. I had that issue as well on my open station M9. I looked at everything from the in tank pickup to the fuel lines, nothing. Then on a lark, I bought a new sediment bowl, brass mesh filter, spring, water float and gasket and replaced everything. It's full now. I believe it was the rubber gasket. Mine would lope all the time like is had a race cam in it. Never lacked for power, just ran terrible, wouldn't smooth idle for beans.

You do have the knurled knob closed on the top of the pump right?

 

[dvcochran]

It should be full to the top. You are sucking air somewhere. I had that issue as well on my open station M9. I looked at everything from the in tank pickup to the fuel lines, nothing. Then on a lark, I bought a new sediment bowl, brass mesh filter, spring, water float and gasket and replaced everything. It's full now. I believe it was the rubber gasket. Mine would lope all the time like is had a race cam in it. Never lacked for power, just ran terrible, wouldn't smooth idle for beans.

You do have the knurled knob closed on the top of the pump right?

I believe I know the knob you are talking about. Maybe 3/4" to 1" in diameter?

 

[dvcochran]

SidecarFlip, I could not Kubota's part diagram site to pull so I went through Messicks. Are you talking about part number 060 on the injection pump diagram?

 

[Hayroller]

I had a

I think this same problem started last year with my M9. I thought I had gotten bad fuel because the tractor would run normally then loose power almost stalling then run normally again for a few minutes. I drained the tanks (did not remove them), removed the crossover tube and inspected. I tested the fuel pump which seemed to pump strong in a bucket. Replaced the fuel filter and separator filter and added fuel from another source. The tractor ran fine last cutting of last year and all winter. The tractor (1200 hours) ran strong all first cutting and baling this year. Saturday, I had the bush hog hooked up and it started doing the same thing again. I limped it back to the shop and left it. I used it this morning moving hay for about an hour and it did fine. Then it started stalling worse than ever and I barely got back to the barn.
There is fuel in the separator and it is clean as a whistle. I blew air through both of the vent tubes. When I blow through the right side tube (injection pump side of tractor) fuel/mist blows out the other vent tube. I looked at the hand pump on top of the filter housing and it is pushed all the way in and will not move. I do not recall this from the last repairs. I have been looking at the fuel system diagram on the Kubota website but nothing seems obviously wrong.

I honestly don't know where to start. I am hoping some of the folks on here can lend me a hand.

 

[Hayroller]

I had a similar issue with our M135Gx last summer..but it would stall but would start after a bit of cranking..i blowed everthing from the filter back to the water separator..still did the same thing..i was about to pull my hair out...had hay down and rain was forecast...i was leaning to a weak lift pump but was told they rarely fail..especially on a 600 hr tractor..i finally pulled the seperator and took it apart...everthing looked fine but in a elbow thier was rements of a grass hopper that evidently flew in the tank refueling...problem solved..my mistake was not blowing thru the separator..i took the fuel line off at the separator and could hear bubbling in the tank so I assumed all was clear.

 

[SidecarFlip]

I believe I know the knob you are talking about. Maybe 3/4" to 1" in diameter?
[/QUOTE


That it. On top of the pump facing you with the hose coming off it. Opening it allows any air to be liberated from the pump (when the engine is running) It feeds the entrained air back into the injector fuel return line through the one way valve and back to the fuel tank. Needs to be closed at all times, except when bleeding the system (purging entrained air.

 

[SidecarFlip]

Never had an issue with any blockage in the fuel lines but I do use Powerservice winter and summed additive in every load of fuel and I also add biocide to my bulk tank that I fill the units from. One nice feature on the M series is, the saddle tanks can be drained without removing them from the tractor. Each have a bung fitting on the bottom you can remove the drain / flush the tanks if necessary.

 

[JerryMT]

I think this same problem started last year with my M9. I thought I had gotten bad fuel because the tractor would run normally then loose power almost stalling then run normally again for a few minutes. I drained the tanks (did not remove them), removed the crossover tube and inspected. I tested the fuel pump which seemed to pump strong in a bucket. Replaced the fuel filter and separator filter and added fuel from another source. The tractor ran fine last cutting of last year and all winter. The tractor (1200 hours) ran strong all first cutting and baling this year. Saturday, I had the bush hog hooked up and it started doing the same thing again. I limped it back to the shop and left it. I used it this morning moving hay for about an hour and it did fine. Then it started stalling worse than ever and I barely got back to the barn.
There is fuel in the separator and it is clean as a whistle. I blew air through both of the vent tubes. When I blow through the right side tube (injection pump side of tractor) fuel/mist blows out the other vent tube. I looked at the hand pump on top of the filter housing and it is pushed all the way in and will not move. I do not recall this from the last repairs. I have been looking at the fuel system diagram on the Kubota website but nothing seems obviously wrong.

I honestly don't know where to start. I am hoping some of the folks on here can lend me a hand.

Intermittent failures like this are very difficult to track down.
I see you're from the SE part of the country where high humidity is common. Have you checked the fuel tank outlet for crud? Sometimes floating bacterial sludge or other debris can intermittently block the tank outlet. Draining the tank won't necessarily get this stuff out. When the problem occurs, check the tank out flow. If it's stopped or just dribbles, try blowing compressed air through the tank outlet to see if that clears up the problem. If you find this problem, it's usually caused by condensation in the tank and that's what the bacteria need to live (they live at the fuel/water interface). Keeping the tank full will minimize condensation and a biocide will kill the bacteria.

Do you have a lift pump ahead of the IP on this tractor. Does it have a screen on the inlet side that can clog? It could also have an intermittent failure. These type of pumps usually deliver 3-5 psi fuel to the IP so you might check the outlet pressure. Check the filter head casting . There could be something clogging there.

 

[dvcochran]

Can you confirm that turning the knob Clockwise closes it? Just want to be sure.
Work kept me away from the tractor today but plan to work on it tomorrow.

So you did not replace the complete separator? Just the bowl and assorted parts? I see the whole thing on line for about $70 aftermarket and Messick's shows it as not available. I will check at my local dealer.

Here is my plan; tell if it makes sense to you:
The tractor will be cold so I am hoping it will run long enough to get the loader off. If it is stalling right away maybe that will aid in the troubleshooting but with loader on it is a Lot harder to get at the fuel system.
My plan right now is to work from the injection pump back to the tanks, line and component at a time, looking closely for trash/leaks.
Replacing the lines as I go.
All of the clamps are the spring type. Would you suggest replacing them with screw clamps?
Take the separator back off and give it another good look, replace the bowl O-ring, and fill it completely full of fuel.
Replace the main fuel filter and little gasket.
Replace the lines from the tank to to the separator, separator to fuel pump, fuel pump to main fuel filter, filter to injection pump.

Am I right in thinking a crack in one of the vent lines would show up as a leak but not cause a running issue (as long as not blocked)?
What purpose does the check valve in the vent line serve (Fig. 206 on A14000 Fuel Pipe diagram)?

I have been adding Power Services winter additive (grey bottle) and algaecide (white bottle/green label) since the problems last year.
Thinking about buying an inspection camera to look inside the tanks. I had a skid steer with a bad case of algae and it looked like caked up sand or dirty chalk.

Any other suggestions?

 

[SidecarFlip]

Can you confirm that turning the knob Clockwise closes it? Just want to be sure.
Righty, tighty, lefty Lucy....

Work kept me away from the tractor today but plan to work on it tomorrow.

So you did not replace the complete separator? Just the bowl and assorted parts? I see the whole thing on line for about $70 aftermarket and Messick's shows it as not available. I will check at my local dealer.
My dealer had all the parts in stock I prefer my dealer over Messicks anyway. Why pay shipping

Here is my plan; tell if it makes sense to you:
The tractor will be cold so I am hoping it will run long enough to get the loader off. If it is stalling right away maybe that will aid in the troubleshooting but with loader on it is a Lot harder to get at the fuel system.
Learned a good trick, if you will, from my Kubota Tech at the dealership about getting the ring off the fuel separator. Use a pair of oil filters pliers like HF sells. Not the vice grip kind, the ordinary hinged ones and put a little PBlaster on it ahead of time. The ring uscrews easy then and the loader isn't in the way. Actually, if you have an open station M9, there is a bracket welded to the FEL frame right in front of the floor pan. That is where the separator is supposed to go when there is a loader attached. No one ever relocates it seems like,

My plan right now is to work from the injection pump back to the tanks, line and component at a time, looking closely for trash/leaks.
Replacing the lines as I go.
All of the clamps are the spring type. Would you suggest replacing them with screw clamps?
I'm still using the OEM spring clamps but you can use worm clamps if you want to.

Take the separator back off and give it another good look, replace the bowl O-ring, and fill it completely full of fuel.
As suggested, blow back through the infeed line from the separator to the fuel tank as well.

Replace the main fuel filter and little gasket.
Replace the lines from the tank to to the separator, separator to fuel pump, fuel pump to main fuel filter, filter to injection pump.

Am I right in thinking a crack in one of the vent lines would show up as a leak but not cause a running issue (as long as not blocked)?
I would think so.

What purpose does the check valve in the vent line serve (Fig. 206 on A14000 Fuel Pipe diagram)?
Keeps the excess fuel from the injectors flowing the right way, back to the fuel tank.

I have been adding Power Services winter additive (grey bottle) and algaecide (white bottle/green label) since the problems last year.
Thinking about buying an inspection camera to look inside the tanks. I had a skid steer with a bad case of algae and it looked like caked up sand or dirty chalk.

Any other suggestions?

harbor Freight has a dandy one for $49.95, I have one. I know all about algae. Cost me over a grand to rid my pickup truck of that crap and I did all the work myself.

 

[dvcochran]

I started taking lines off yesterday. Found what looks like grass in the line at the inlet to the separator. I could not see it until I cut about an inch off the line (to take to the parts store to get the correct size). Oddly that separator bowl and screen are clean. Per the diagram the hoses in/out of the separator were swapped. Would this matter?
I went ahead and dropped the tanks and cleaned them out, carefully trying to look for contamination. There was a little trash in the tanks but nothing that looked like grass. The pickup tube runs down to the crossover nipple on the RH tank so it is easy to see how any trash is going to find its way into the system. I left the tanks out in the sun to dry out and will inspect again. I am changing the lines and filters and will disassemble the separator and clean out. My Kubota dealer did not have the separator gasket in stock so I may have to get creative until it arrives.
I also use Power Services Kleen (white or grey bottle) and algaecide in my transfer tank. Since I washed the tanks out I think I will add some 911 in the first couple of loads as well. Damn hard to fully drain when washing them out.

 

[SidecarFlip]

Might not be a bad idea (I'd use Powerservice Bio-Kleen) which is a straight pesticide formula). Comes with all the warnings on the bottle...lol

The tanks are a bugger to wash out. That little bung on the bottom isn't the best avenue for cleaning and the tank straps are kind of a PITA to get off.

I suspect that little bit of grass may be your issue and as far as swapping the hoses, I have no clue. I really dislike taking the loaders off either one. Kubota don't allow much in the way of excess hose length for the couplers and on my open station, the valving and the couplers are very tight against the side of the tractor. I do a lot of swearing and bust my knuckles every time I dismount it.

On the cab tractor, dismount is much easier as the valving and couplers mount down low (the FEL actuation is via a cable setup with the in cab controls mounted in the cab on a metal post), so everything external is really accessible. Was nice of Kubota to design the loader uprights right in front of the engine oil filter and fuel bowl. Both are a PITA to remove and replace, especially the oil filter. I always make a mess when changing the oil filter as the oil runs down over the side of the engine and drips on the fittings below.

How was the crossover hose? Was it clean? That is the lowest point in the fuel system. You have to remove the metal shield to get it off (4 bolts) and 2 spring clamps.

 

[dvcochran]

I ran the tractor for a few hours today moving hay and had no issues. Hopefully the problem is gone.
You are 100% correct on the loader hookups, they could have spread things out less than an inch more and made a huge difference.
The crossover was clean. I was going to replace it just because of its age but Kubota wants almost $50 for it. I tried a piece of flexible hydraulic hose that is fuel rated but it was just a little too small to get on.
I had a damn hard time bleeding the system. Took a long time get fuel to the front line. Once it finally hit it went pretty fast.
I don't know if algaecide would have cleaned out what I found but I am going to run it more frequently.

 

[SidecarFlip]

I ran the tractor for a few hours today moving hay and had no issues. Hopefully the problem is gone.
You are 100% correct on the loader hookups, they could have spread things out less than an inch more and made a huge difference.
The crossover was clean. I was going to replace it just because of its age but Kubota wants almost $50 for it. I tried a piece of flexible hydraulic hose that is fuel rated but it was just a little too small to get on.
I had a damn hard time bleeding the system. Took a long time get fuel to the front line. Once it finally hit it went pretty fast.
I don't know if algaecide would have cleaned out what I found but I am going to run it more frequently.

Never replaced either of mine but I'll keep that 50 buck price in mind if I ever do.

My cabin M9 isn't too bad (loader couplers), but the open station is a real pizzer to get off and on. No room between the valve and the upright and the hoses are just long enough to hook up, I mean just. I added hydraulic street Ell's to space the couplers a bit but I still have to grab them with Channel Locks to get them to release and of course the joystick housing is also in the way. Terrible design.

 

[dvcochran]

Do you have trouble with your remotes leaking when you have something hooked up? I have changed the O-rings a couple of times but it doesn't seem to make much difference.