I have a Kubota L3400 HST that suddenly died on me. When I try to start it, it turns over and runs for maybe a second at most and dies again. I can repeat this over an over. It will only run for this second when turning the key from position 1. If I try from position 2, nothing happens.
L3400 starts and dies within a second
- Thread starter Kleus
- Start date
Bad lift pump or a faulty fuel cutoff solenoid. You need to check the pressure at the hand pump on top of the spin on fuel filter to make sure it's firm and pressurized before anything else.
I appreciate the quick reply. I am not familiar with ever seeing a hand pump on top of the fuel filter assembly. Could you elaborate please?
From following posts on this site I've learned (some?) fuel cutoff solenoids have a start position and a run position. Start pulls the solenoid into place and the weaker run coil holds it open. Your run winding may be open. Get a schematic and check out the solenoid.
Most Kubota's at least the mechanical injected ones have a plunger type pressure pump on top of the fuel filter housing that initially pressurizes the fuel system so the pump will draw fuel. If the pump knob is soft, there will be no initial pressurization of fuel and the motor will start but shut right off.
I'd start with that. It's the easiest thing to diagnose.
I'd start with that. It's the easiest thing to diagnose.
The Scottish version of the WSM shows both pull and hold coils of the stop solenoid wired together.
What is also apparent is the OPC timer's involvement with the solenoid.
If the tractor's wiring looks like this one, start by checking the 5 amp OPC timer fuse.
The Scottish wiring may not be the same as the North American tractor's.
Dave
What is also apparent is the OPC timer's involvement with the solenoid.
If the tractor's wiring looks like this one, start by checking the 5 amp OPC timer fuse.
The Scottish wiring may not be the same as the North American tractor's.
Dave
it ain't got a hand pump filter housing assembly on a L3400HST. It's got a cheap plastic housing with a filter inside of it no pump on it
it has a lift pump on the side of the block, no manual lever on it (unfortunately). Seldom failure point. Usually when the other techs suspected a failed lift pump, I'd ask them to check for fuel in the crankcase. If none, do a fuel flow test from tank to lift pump. Should flow on it's own (tank is mounted higher than the filter housing). If no flow, has a restriction in the line somewhere-or plugged filter or filter housing restriction. Just work your way back.
need fuel air compression to run. Which one does it lose within a second or two after starting initially? I am suspecting a shutoff solenoid or wiring or control issue but the issue was not described very well, so that's all we have to go on.
it has a lift pump on the side of the block, no manual lever on it (unfortunately). Seldom failure point. Usually when the other techs suspected a failed lift pump, I'd ask them to check for fuel in the crankcase. If none, do a fuel flow test from tank to lift pump. Should flow on it's own (tank is mounted higher than the filter housing). If no flow, has a restriction in the line somewhere-or plugged filter or filter housing restriction. Just work your way back.
need fuel air compression to run. Which one does it lose within a second or two after starting initially? I am suspecting a shutoff solenoid or wiring or control issue but the issue was not described very well, so that's all we have to go on.
19thSF
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B2650, loader, MMM, pallet forks, tooth bar, rear blade, JD 318 w/plow, JD X350
This may be a long shot, but my tractor was doing something similar. It turned out to be a clogged fuel cap breather port that was preventing air from getting into the tank, which created a vacuum, preventing fuel flowing from the tank.
As I say, a long shot.
Good luck with your problem. I hope that is is resolved by 2021!
As I say, a long shot.
Good luck with your problem. I hope that is is resolved by 2021!
On my B2650, if the treadle pedal isn't sitting just right in the center, I will get this exact scenario. Starts instantly for a second and then shuts down.
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This is a short compressed clip of what happens. Not good quality video but the sound is right on.
19thSF
Active member
Lifetime Member
Equipment
B2650, loader, MMM, pallet forks, tooth bar, rear blade, JD 318 w/plow, JD X350