L3301 HST cranks, starts briefly then stalls

[Joeb1]

I’ve been through several threads and I don’t think I found the solution. I’ve cleaned the fuel/water, separator, and replaced the fuel filter. I have ensured there is no air in the system. I’ve confirmed that I have fuel going through the fuel pump. The tractor cranks, starts briefly, when I release the key back to the run position, it stalls.

 

[North Idaho Wolfman]

On an older tractor i would say you have a Run solenoid / Fuel shut off solenoid issue.
But with a newer tractor that is computer controlled you can't have that issue.

If it is doing it rather consistently, My best guess, with limited information that we have, is you have a main switch issue, that is cutting power to the engine controls when the key is released from the start position.

One other possible odd scenario is that there is a safety switch issue that is keeping it from running, but that's a long shot because most of those safety switch issues should also keep it from cranking too.

 

[Edke6bnl]

Mine did that and it was a bad key switch

 

[Joeb1]

Thanks for your insight. By “main switch” do you think it could be the ignition switch?

 

[North Idaho Wolfman]

Thanks for your insight. By “main switch” do you think it could be the ignition switch?

Yes ignition=main switch.

 

[Joeb1]

Ok, I’ve verified that the ignition switch is not the culprit. I’ve visited my local Kubota shop and they seem to think it’s a fuel issue. Possibly a clogged injector. Anyone experienced this and possibly fixed it?

 

[JasonW]

How long would it stay running if you held the key in the start position? Does it run smooth when it is running?

Did your filters look clean? How would something get past the filters to an injector? I would think if it was one clogged injector it would run just poorly.

When it shuts off does it seem like it’s starving for fuel or acting like you just turned the key off? Does it turn off immediately or a few seconds after releasing the key?

 

[Joeb1]

It will run as long as I hold the key in the start position. It runs smooth.

I didn’t cut the fuel filter open but the water/fuel separator had some gunk in it. I cleaned it thoroughly. One theory is that some of the fuel has gelled at the injector.

I don’t know if I can tell if it sounds like it’s starving for fuel. I would say it’s acting like I just turned the key off or just ran out of fuel.

it turns off a few seconds after I release the key.

 

[North Idaho Wolfman]

Ok, I’ve verified that the ignition switch is not the culprit. I’ve visited my local Kubota shop and they seem to think it’s a fuel issue. Possibly a clogged injector. Anyone experienced this and possibly fixed it?

A fuel delivery issue would not just cut off and neither would an injector issue.
How did you figure out it's not the Ignition switch?

 

[JasonW]

It will run as long as I hold the key in the start position. It runs smooth.

I didn’t cut the fuel filter open but the water/fuel separator had some gunk in it. I cleaned it thoroughly. One theory is that some of the fuel has gelled at the injector.

I don’t know if I can tell if it sounds like it’s starving for fuel. I would say it’s acting like I just turned the key off or just ran out of fuel.

it turns off a few seconds after I release the key.

What part of Alabama are you in? Anywhere in Alabama currently you shouldn’t have fuel gelling.
I’m leaning towards something electrical.

 

[Joeb1]

When I spoke to the folks at the Kubota dealership, they said if the tractor was starting, even briefly, that the ignition switch was not the problem. Do you have reasons to believe it is the ignition switch?

 

[JasonW]

When I spoke to the folks at the Kubota dealership, they said if the tractor was starting, even briefly, that the ignition switch was not the problem. Do you have reasons to believe it is the ignition switch?

Well if it stays running as long as you hold the key in the start position and shuts off when it’s returned to the run position. Test the key switch pin outs with a multimeter.

 

[North Idaho Wolfman]

When I spoke to the folks at the Kubota dealership, they said if the tractor was starting, even briefly, that the ignition switch was not the problem. Do you have reasons to believe it is the ignition switch?

That has got to be one of the worst "testing" methods I've ever run across.
Also some of the worst dealer supplied info to you.

The start and run circuits are 2 different circuits and 2 different switch output positions.

You need to follow the WSM to troubleshoot it properly and not just guess that something is OK.
I'm not going to suggest you take it to whatever dealer you talked to because they are not the brightest bulb in the light fixture!

 

[Runs With Scissors]

Since the ignition switch is responsible for turning the tractor "on AND off", simply "dismissing" the switch as a possibility, sounds like a mistake to me.

That kind of "troubleshooting" is the first step in loading up a "parts cannon".

(I know this because I have been guilty of firing the "parts cannon" once or twice.)

I would respectfully submit that simply 'dismissing" things is the #1 mistake made in troubleshooting anything.

It sounds like it's time to get the WSM out, and start testing, (without skipping steps)

 

[GreensvilleJay]

If Kubota kept same wiring philosophy, the 'main' switches 'on/run' pole is the one with a red/wht wire on it. Hopefully you do have the wiring diagram.
Attach a 12 volt light to it(better than DMM ) . turn key on ,light lights, turn key to start, light should still be on, release from start, light should still be on.

If this test works then it is NOT the main switch. For me to help further NEED the wiring diagram.

Since it will start ,in the 'start' position ,unlikely a fuel problem, perhaps the 'run or stop' engine solenoid ? different models have one or the other. Whichever it is, I'd disable it then test start,see if it runs inthe 'on' position as you can manually shut engine down by 'moving' the 'run/stop' solenoid.

 

[PoTreeBoy]

There's a wiring diagram in the WSM, available on KubotaBooks. Here's the starting system:

This is a common rail system and doesn't have a fuel solenoid. The culprit is almost certainly the key switch. Test it for continuity from bat to ac in the start and run positions.

 

[North Idaho Wolfman]

Thinking about this more, one other component pops up as a possible failure, the crank sensor.
If it's bad enough it could just not send a signal to the ECM to tell it the motor is spinning?

 

[PoTreeBoy]

Thinking about this more, one other component pops up as a possible failure, the crank sensor.
If it's bad enough it could just not send a signal to the ECM to tell it the motor is spinning?

If I understood correctly, Joe said it runs as long as it's in the start position. He could get a longer test by jumpering the BAT terminal to AC and starting it.

 

[North Idaho Wolfman]

If I understood correctly, Joe said it runs as long as it's in the start position. He could get a longer test by jumpering the BAT terminal to AC and starting it.

Yes possibly, but you've really got to be careful jumping anything on a computer controlled tractor.

His best bet would be find a better dealer and have them read it with a computer!

 

[whitetiger]

Thinking about this more, one other component pops up as a possible failure, the crank sensor.
If it's bad enough it could just not send a signal to the ECM to tell it the motor is spinning?

If no reading is detected, the hour meter display would have a "P" code in the hour meter display.