I have an MX5000. Starts fine and runs good for 15 minutes. It then wants to stall under load and won't rev past 1500. I turn it off and leave it in the cold for 90 minutes and all is well again for 15 minutes. I bled the system. fuel filter was replace 10 hours ago as well as the air and oil filters and oil. All ran well until two days ago. I thought that maybe it was a gas tank venting problem so I cleaned the cap and cleared away any ice and snow. I have to think that this is a vacuum problem but apparently not. So, any other recommendations, suggestions would be greatly appreciated as we're in for a lot of snow and the dealer is backed up for 2 weeks. Thanks.
loses power after 15 minutes
- Thread starter Timberbank
- Start date
Sure sounds like a fuel problem. Can you remove a line just before the filter to be sure it's all clear to that point? Or maybe a gasket not sealing in the new filter installation? Try running it without the fuel can on, or just setting loose.
85Hokie
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first thought would be algae inline/filter - but after sitting a while somehow clears itself up....which would be strange. Do you have any treatment in the fuel? Algaecide in tank?
If you can - pull the fuel line off the anywhere that is accessible - let it drain into a glass jar or something you can see through....the rate of pour should be a constant stream - if it slows, remove you filler cap, if still slow or slowing down - you have a something clogging the fuel supply in the tank - and after it shuts down, it moves away to allow fuel to flow once again.
Also - take this glass sample inside and allow to sit still - any separation near the bottom?
I have heard that MX5000 have a problem with water getting in the fuel from either condensation or being left outside uncovered. Here is another post on your problem:
http://www.ssbtractor.com/wwwboard/view_all.cgi?bd=kubota&msg=25725
(Edit - D2Cat - quick on the trigger!)
If you can - pull the fuel line off the anywhere that is accessible - let it drain into a glass jar or something you can see through....the rate of pour should be a constant stream - if it slows, remove you filler cap, if still slow or slowing down - you have a something clogging the fuel supply in the tank - and after it shuts down, it moves away to allow fuel to flow once again.
Also - take this glass sample inside and allow to sit still - any separation near the bottom?
I have heard that MX5000 have a problem with water getting in the fuel from either condensation or being left outside uncovered. Here is another post on your problem:
http://www.ssbtractor.com/wwwboard/view_all.cgi?bd=kubota&msg=25725
(Edit - D2Cat - quick on the trigger!)
I'm having trouble figuring out why it runs fine for 15 minutes and then loses power. I'm going to try running it with the cap off and also blowing out the vent holes in the cap with compressed air. Bad fuel or a blocked line would mean that would run rough as soon as I start the tractor no? Is there anything in the fuel system that would change as the tractor heats up after 15 minutes? It doesn't run hot, just it's normal operating temperature.
armylifer
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It sounds to me like you are having weather related fuel gelling problems. Are you using any grade of biodiesel? That can cause all kinds of problems in cold weather. Also, have you tried adding an anti-gel fuel additive such as Diesel Kleen Power Service in the WHITE bottle?
Even if you are using straight No.2 Diesel fuel it will start to gel at ~15 degree Fahrenheit. Some grades of biodiesel can start to gel at as high as 32 degrees.
If the fuel in the tank is partially gelled little crystals of wax will form and accumulate in the fuel filter and clog it up. Then when you shut the engine down for 15 minutes, the engine will heat up the fuel in the filter and let it flow freely again until enough wax has accumulated again in the fuel filter from the fuel tank and it exhibits the running problem again. This will repeat until the fuel in the tank is warm enough to stay un-gelled.
Try adding the fuel additive and see if your problem goes away. I think it will.
Even if you are using straight No.2 Diesel fuel it will start to gel at ~15 degree Fahrenheit. Some grades of biodiesel can start to gel at as high as 32 degrees.
If the fuel in the tank is partially gelled little crystals of wax will form and accumulate in the fuel filter and clog it up. Then when you shut the engine down for 15 minutes, the engine will heat up the fuel in the filter and let it flow freely again until enough wax has accumulated again in the fuel filter from the fuel tank and it exhibits the running problem again. This will repeat until the fuel in the tank is warm enough to stay un-gelled.
Try adding the fuel additive and see if your problem goes away. I think it will.
Kubota Newbie
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M4500, New Idea Cut-Ditioner, JD 14T Baler, IH "Plow Chief" plows, Oliver Rake
Last time I had a problem on my M4500 like that it was gas in the fuel. Not enough to detonate/ping/rattle etc. But it had no power, seemed to idle ok, wouldn't rev up etc. Ran smooth enough but wouldn't pull itself up a hill when hot. Give it the smell test.... it doesn't take much to cause a problem.
coachgeo
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L225 w/woods Few Mowers & Back Blade, D722 in Motorcycle (Triumph Tiger), LMTV
Need more information in your user info. Stouffleville means nothing to 99% of us. That could be in South TX or North Dakota.
Please update your info for us Geographic Ineptiphiles.
It sounds like a fuel starvation problem. check for fuel flow through the filters. Also make sure the lift pump is working! We have had some problems with lift pump failure on that series of engines. When the pump fails the symptoms are just like yours. ( the lift pump is the small pump on the side of the injector pump) The reason it works OK for 10- 15 minutes is because the fuel tank is higher than the filters and the injection pump so gravity fills the system when it is shut down but when you start it it gradually loses fuel because the fuel cannot get through the failed pump quick enough.
Ed
Whitchurch-Stouffville Ontario Canada, L4A2T7. Current temperature is +1F. Tonight's low will be -4F. High tomorrow, +3F. Eight inches of snow on the ground.
Thanks. That makes a great deal of sense. Can a DIY guy check a lift pump or is that a dealer mechanic fix?
Determine which of the fuel lines is discharge from the pump. Remove it then crank the engine, fuel should spurt out. if the pump is failed there will be very little discharge. ( the discharge hose goes to the main fuel filter)
You can use fuel additives in that tractor if you want to ( no DPF) but it is designed to operate properly on available fuel in north America without additives.
armylifer
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I would not be looking for anything mechanical at this point. Try the easiest solution first. You already said that it runs fine for 15 minutes and then shuts off. Try the fuel additive first. It cost very little to try and if you need to start looking for a mechanical solution after that you have not really lost anything by trying the cheapest solution first. Give how cold it is by you, it is a guarantee that the fuel is clouding. That is the nature of diesel fuel in cold weather.
Sounds like restricted fuel delivery. What's the temperature where you're tractor is located?
Are you using summer fuel? That can wax up at ~28°F in the filter or on the tank outlet strainer, etc .Ice from condensate can form on the tank outlet strainer or on the filter itself. If you can get the tractor into a warm place the wax will dissolve or the ice will melt. or if your fuel filter is metal, you can try using a blow dryer on it to warm it up. Make sure that you don't have any mechanical damage to the fuels lines.
Hope this helps.
Yes however, why would it start and run fine for 15-20 minutes and then start to stall under load and not rev past 1500? It's something that's changing as the tractor gets up to it's operating temperature. Frustrating.
armylifer
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BX1860, FEL, RCK54P MMM, BB1548 Box Scraper, Quick Hitch, Piranha Bar, BX6315
What have you tried so far? Several people have mentioned additives to prevent gelling in the fuel. We have experienced exactly the same symptom you describe and solved the problem with fuel additives. Tell us what you have done so far to eliminate solutions that don't work so we can move on to different suggestions. Help us to help you.
85Hokie
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or.....something that is being drawn into the fuel line via the tank, once a suction is placed on the tank, the small debris finds its way to the line and restricts flow. Under load requires more fuel per unit of time, maybe your restriction is such that a certain amount of fuel is allowed - yet once you demand more, it cannot deliver. AS we have said, add a algae additive and see if any difference is noticed.
And as eserv said - it could be a fuel delivery problem with the lift pump. The algae treatment is easy and quick - the lift pump will require more energy/time to fix.
But I would start with a $15 bottle of fuel treatment!