L3301 cranks but will not start

kphend

New member

Equipment
L3301 HST
Jun 6, 2019
6
0
0
Cincinnati, Ohio
Tractor is about 4 years old, has about 135hrs. Tractor was running and then stopped. I drained the fuel/water separator and removed a little water. Still will not start. I noticed the electric fuel pump is not working. Checked all the fuses, they are fine. I checked voltage at the connector at the fuel pump with the key on and get 0 volts. Printed off the electrical portion of the workshop manual and started trouble shooting. Removed surround around steering wheel and checked relays. They are fine. Also checked voltage on the high rail pressure, it is supposed to be getting 5V, I get 0 volts. Removed the ECU and checked to make sure pin 50 was getting battery voltage and it is. Baffled and frustrated. ?! A gas engine needs fuel, air and spark...a diesel engine needs fuel and air. Emission from a small diesel tractor with a control unit with 60 wires.....:mad:

Please help.... dealer wants over $100 to troubleshoot.
 
Last edited:

BruceP

Well-known member

Equipment
G5200H
Aug 7, 2016
835
353
63
Richmond, Vermont, USA
Those electric 'lift pumps' are notorious for quitting. Many others on this forum have needed to replace them.

To validate if your pump is bad, disconnect the wire and check for voltage (12v) when the key is 'on'. If you indeed see voltage into the pump, you can also try rapping it with screwdriver-handle to see if it starts running.

In any case, if you have voltage and pump not running -- REPLACE it.

There are MANY options to replace a 'lift pump'. You could go with anything from an original Kubota part.... all the way to a chineese knock-off shipped from china. For me, I bought an Edelbrock fuel pump at local autoparts store ==> https://www.edelbrock.com/universal-micro-electric-fuel-pump-38-gph-144-lph-gasoline-e85-17301.html

The rotary-type pump is a lot quieter than the original pump. (no more TickaTicaTicka....)
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
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Those electric 'lift pumps' are notorious for quitting. Many others on this forum have needed to replace them.

To validate if your pump is bad, disconnect the wire and check for voltage (12v) when the key is 'on'. If you indeed see voltage into the pump, you can also try rapping it with screwdriver-handle to see if it starts running.

In any case, if you have voltage and pump not running -- REPLACE it.

There are MANY options to replace a 'lift pump'. You could go with anything from an original Kubota part.... all the way to a chineese knock-off shipped from china. For me, I bought an Edelbrock fuel pump at local autoparts store ==> https://www.edelbrock.com/universal-micro-electric-fuel-pump-38-gph-144-lph-gasoline-e85-17301.html

The rotary-type pump is a lot quieter than the original pump. (no more TickaTicaTicka....)
You totally missed he has no power to the pump! ;)
 

Fordtech86

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Lifetime Member

Equipment
L3200
Aug 7, 2018
4,708
5,480
113
Pineville,LA
Just looking at the wiring diagram for your tractor and what you have said you have checked (besides checking the ground circuit for the ecu) it looks like the engine ecu went out.

Have you checked for the 5 volt reference voltage at any other sensors like the cam or crank sensor, or dpf pressure sensor?

I say that with no experience working on tractors like you have, just from the auto industry with way more modules and wires lol. I think if it were to be the ecu then it would be covered under an extended emission warranty, not sure what it is with Kubota but typical in auto world is 8yr/80,000 miles.
 

North Idaho Wolfman

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Jun 9, 2013
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Sandpoint, ID
Tractor is about 4 years old, has about 135hrs. Tractor was running and then stopped. I drained the fuel/water separator and removed a little water. Still will not start. I noticed the electric fuel pump is not working. Checked all the fuses, they are fine. I checked voltage at the connector at the fuel pump with the key on and get 0 volts. Printed off the electrical portion of the workshop manual and started trouble shooting. Removed surround around steering wheel and checked relays. They are fine. Also checked voltage on the high rail pressure, it is supposed to be getting 5V, I get 0 volts. Removed the ECU and checked to make sure pin 50 was getting battery voltage and it is. Baffled and frustrated. ?! A gas engine needs fuel, air and spark...a diesel engine needs fuel and air. Emission from a small diesel tractor with a control unit with 60 wires.....:mad:

Please help.... dealer wants over $100 to troubleshoot.
Did you disconnect the pump connector then check the voltage, or did you do it connected?
Did you measure the pump resistance?
Did you check if your getting power to the engine relay?
 
Last edited:

kphend

New member

Equipment
L3301 HST
Jun 6, 2019
6
0
0
Cincinnati, Ohio
Did you disconnect the pump connector then check the voltage, or did you do it connected?
Did you measure the pump resistance?
Did you check if your getting power to the engine relay?
I checked the voltage from the connector itself (disconnected from the pump)

I did not measure the resistance, but I did run jumpers from the battery to the pump and the fuel pump runs....but the tractor still would not start.

I did check 12V to the engine relay and it had 12V and checked the relay itself and it is fine.
 

kphend

New member

Equipment
L3301 HST
Jun 6, 2019
6
0
0
Cincinnati, Ohio
Just looking at the wiring diagram for your tractor and what you have said you have checked (besides checking the ground circuit for the ecu) it looks like the engine ecu went out.

Have you checked for the 5 volt reference voltage at any other sensors like the cam or crank sensor, or dpf pressure sensor?

I say that with no experience working on tractors like you have, just from the auto industry with way more modules and wires lol. I think if it were to be the ecu then it would be covered under an extended emission warranty, not sure what it is with Kubota but typical in auto world is 8yr/80,000 miles.
I am also fearful it is the ECU. Another thing I failed to mention...when I run the self diagnostics through the dash. It come up with 3 temperatures that were negative -459 degrees.
 

Fordtech86

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Equipment
L3200
Aug 7, 2018
4,708
5,480
113
Pineville,LA
I am also fearful it is the ECU. Another thing I failed to mention...when I run the self diagnostics through the dash. It come up with 3 temperatures that were negative -459 degrees.
Maybe whitetiger or lugbolt could offer some more Kubota Dealer experience, but in my world a temp sensor would read -40 degrees if unplugged or not receiving voltage. Voltage and ground for your temp sensors appear to come from the engine ecu as well. I would verify the ground circuits for the ecu before condemning it but since it cranks it appears it should be good. Also ask the dealer what the warranty coverage is on the ecu.
 

sheepfarmer

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L3560, B2650, Gator, Ingersoll mower
Nov 14, 2014
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MidMichigan
The latter observation of three temperatures makes it sound like you might have temperature or airflow sensors that have become disconnected or bad, and ecu won't let tractor start until they or it is fixed.
 

lugbolt

Well-known member

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ZG127S-54
Oct 15, 2015
4,807
1,575
113
Mid, South, USA
Only way to diagnose is diagmaster-via kubota dealer. There is no other way, unless you want to start throwing parts at it, and that gets REAL expensive very quickly.

Remember--these things have a 5 year emissions warranty, so there's a possibility that it may not cost you anything; but you'll never know until a dealer diagnoses it.
 

kphend

New member

Equipment
L3301 HST
Jun 6, 2019
6
0
0
Cincinnati, Ohio
Only way to diagnose is diagmaster-via kubota dealer. There is no other way, unless you want to start throwing parts at it, and that gets REAL expensive very quickly.



Remember--these things have a 5 year emissions warranty, so there's a possibility that it may not cost you anything; but you'll never know until a dealer diagnoses it.
Lugbolt, I tried looking up emission related warranty and I never came up with anything beside the factory 2 or 3 year warranty. Is there somewhere you could point me for the 5 year warranty. If so, you have provided me with the best news I've heard today.

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sheepfarmer

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Equipment
L3560, B2650, Gator, Ingersoll mower
Nov 14, 2014
4,440
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It should be in separate pamphlet with the paper work you got with the tractor. It was federally mandated. Even so the $100 dollars your dealer wants to charge is cheap compared to the damage you could do mucking around in the fuel supply system in the high pressure common rail systems. No insult intended to your mechanical skills, it's just hard in these computer controlled things. If you dont run across a disconnected wire dangling loose, that would be the route I'd recommend.. Let us know what you learn please.
 

kphend

New member

Equipment
L3301 HST
Jun 6, 2019
6
0
0
Cincinnati, Ohio
The dealer picked it up Monday. We'll see what the say. I'll post their solution, so maybe someday it will help someone on here

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lugbolt

Well-known member

Equipment
ZG127S-54
Oct 15, 2015
4,807
1,575
113
Mid, South, USA
Just as advice for those that might be searching for L3301 won't start...

again I can't stress it enough. Diagmaster is the only game in town (so to speak) to work on Kubota's. K-OBD isn't available yet, at least not for tractors. I think it works with some of the mini-excavators. That means that no hand-held diagnostic scanners will work, nothing over the counter, Kubota dealer only. There are thousands of things that can go wrong and it would be foolish to try to isolate them without diagmaster's help. Why? From a consumer's standpoint, an electric lift pump is fairly cheap, but a supply pump...about $3500 and change for the smaller ones. Fuel rail pressure sensor? $1000+. Differential pressure sensors? Not cheap either. You can't replace an injector without registering the serial number with the ECU-requires diagmaster. You can't swap injectors from cylinder to cylinder and expect the engine to run properly, without diagmaster. Actually doing stuff like that "can" destroy the engine. They run on the edge of self-destructing anyway and don't really need any "help" from untrained "techs". Throwing parts at it will end up with unnecessary expenses in comparison to having dealer pick it up and properly diagnose it. Good example is that supply pump, if it's damaged, the dealer is going to want to know WHY before replacing it. Was it water in the fuel? Was it lack of fuel? Defect in the SCV? Warranty might buy a new one, but they darn sure won't buy a second one if it's proven that the dealer didn't do the homework to isolate the root.
 

kphend

New member

Equipment
L3301 HST
Jun 6, 2019
6
0
0
Cincinnati, Ohio
Finally got tractor back from dealer!! Thank you for all who suggested emissions warranty and to take it back to dealer. New ECM and engine wiring harness installed for free. The had it for a long time, but gave me a smaller loaner free of charge too!

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lugbolt

Well-known member

Equipment
ZG127S-54
Oct 15, 2015
4,807
1,575
113
Mid, South, USA
They likely had it a while because tech support works along with warranty. I said in another post a while back that the warranty processes have certainly changed and this is a result of the changes. I'm sure the dealer and Kubota both are appreciative of your patience. There is not a dealer that I know of that is immune to this either. they all have a problem child or two to deal with.