Winter and 3901 cranks but wont start .I checked fuses and 190hrs on it.I cleand the fuel screen and did the bled the air out of the fuel filter.
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Kubota 3901cranks but wont start
- Thread starter Poophead
- Start date
If you said you bled air out of the filter - did you run dry before this started?
If so - you probably need to bleed the injectors too...
If not - some history as to what happened prior to it not starting would be helpful!
You said winter... are you running a winter fuel and/or any additive? What is the temp?
If so - you probably need to bleed the injectors too...
If not - some history as to what happened prior to it not starting would be helpful!
You said winter... are you running a winter fuel and/or any additive? What is the temp?
It ran fine 3 weeks ago . I didnt run the engine til fuel shut it down . I dont use additives but i will now .The temt today is in the 60s.
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The fuel pump is working and there was a little water in the seperator.When i bled the air out of the fuel filter i turned on the key and fuel came out of the vent.
Thanks for your help
Thanks for your help
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I wish it was the bowl .
When the pump is running, there are no leaks .
I dont see any smoke out of exhaust while cranking the engine.
Still stumped.
Thanks for the help
When the pump is running, there are no leaks .
I dont see any smoke out of exhaust while cranking the engine.
Still stumped.
Thanks for the help
whitetiger
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Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
You will not see smoke from a DPF equipped engine! (that is the purpose of the DPF)
There's no flashing lights ,the battery is charged and the motor turns over quick. No water in the seperator now but there was a little but not up to the line.the air filter is clean . I even tried to start it without it .There are no codes flashing either.
Thanks for the help
Thanks for the help
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if you're getting fuel during starting, there should be some white-ish smoke coming from the exhaust pipe.
You say the temperatures in the 60's so we can rule out waxing or ice.
Since you say you don't see any, make sure you have adequate fuel delivery. Start at the tank outlet. there's a strainer in there and it could be partially clogged, allowing just enough fuel to eventually fill the filter. If you pull the fuel supply line at that point, and open the fuel valve, the fuel should come out like a cow peein' on a flat rock! If it just dribbles the strainer is blocked.
If the fuel does gush out, go on to the fuel filter and check the fuel flow at the filter outlet. Again t should gush out. If it doesn't check the filter, the passages in the filter head, etc for blockage. Make sure your filter and any O-rings are installed properly.
If you have good fuel flow at the filter discharge and you have a lift pump, the best way to check that is with a low pressure gauge and a "T" fitting at the pump discharge. You should have 2-4 psi at the pump discharge when you are cranking. f you can't get a gauge on it, there should be a lot fuel coming out as you crank the engine. Some of these lift pumps have a screen on the inlet side. Check that if you have that configuration.
Finally, if there is a bleeder on the injector pump, open that up and crank the engine. lot of fuel should squirt out of there. Finally check to make sure the "return to tank" fuel line flows some fuel when you crank.
these are general trouble shooting methods for diesel engine fuel delivery problems. Kubota's have a few different types of fuel delivery systems and I certainly am not familiar with them but the same general methods apply to them. You can not start a diesel without fuel and air so you trouble shoot fuel delivery and ninety nine times out of hundred you will find crud or a extra o-ring in the filter, etc that interfering with fuel delivery. DON"T MESS WITH THE INJECTOR PUMP UNTILL YOU CHECK THE SIMPLE STUFF AND DON"T USE STARTING FLUID!
Ive checked all that .Today I did check the top high pressure line that goes to the injector pump . I cranked the engine and no fuel to the top .I know its a high pressure line .Where am i missing this at ? They have so many hoses and stuff on
both sides of the egine its hard to see in there.
both sides of the egine its hard to see in there.
The days of the home mechanic being able to diagnose and repair their own equipment are nearly over. there are probably dozens of reasons why a L3901 might not start. it is a common rail engine with electronic control of the injectors through a ECU. there are a multitude of sensors that have to be satisfied to allow the injectors to inject fuel. The only proper way to repair this is to have a Kubota tech connect Diagmaster to it to determine what is and what is not working.
Specifically, what did you check and what did you find? Did you have fuel coming out of the tank to the filter, out of the filter to the lift pump, out of the lift pump to the injector pump....
The engine parts associated with emissions system have a 5 yr warranty, so seems like it would be worth taking it in for diagnosis. Check your pamphlet that came with the tractor, but probably includes fuel delivery/common rail items.