Bad news big repair

[24mph]

How about an engine block heater ? In winter it will prevent he rattling and shaking and big cloud of black smoke. Just don't leave it plugged in too long, maybe 30 min. in single degree temps.

 

[Black Dog 2]

Purchased my M135X in warmer months almost 3 years ago (April 2019). Never thought to see if the glow plugs worked. They actually won’t work if it’s over 41*.
Last winter, I realized the glow plugs weren’t working. Ohmed out wires, looked at wiring for mice damage, water damage, bad grounds, etc. Ohmed out wiring. Thats when I learned the glow plug system in larger kubotas is more complex than I thought. All 4 glow plugs passed electrical testing.
The glow plugs have 2 sensors one for air temp, one for water temp. The ignition switch is also part of the circuit. Then there are 2 relays and a fuse. All of this is controlled by the ECU. Last winter, I replaced
Key switch
water temp sensor
air temp sensor
both relays
fuse

Still no glow plugs. With nothing left to replace or test, I succumbed to a very reputable Kubota dealer. They basically did all the same things I did and replaced one of the new sensors I had already placed.
Still nothing. They called Kubotas double secret probation hotline and Kubota thinks it’s the ECU.

ECU price $6000
ECU Not returnable and no guarantee it will fix glow plugs.

So I’m out of answers. Any thoughts on other possible avenues to pursue?

I have a L6060 with 360 hours and no problems so far. I also have a Cub Cadet SS7360 36HP 4cyl diesel that the glow plugs never worked even after replacing all components related to the glow plus system. I installed a manually activated system from the battery to the plugs with a 40 amp fuse. I turn on the manual switch for 7 seconds and have not had a problem since and it starts in very cold weather within 3 cranks but usually on the first one.

 

[RickB]

to overcome the the ECU derating the motor because the sensors are derated the easiest way would be to find a used glow plug and plug it into the ECU while the glow plug that is actually in the motor is run off a manual switch, if you were really tricky you could figure out what the resistance of the sensor is and just wire in the a resistor so the computer thinks there is a glow plug there. me I would just find another glow plug and it in, actually I would just suck it up and pay for the ECU, or just keep running it the way it is, maybe put a block heater in it to help out on the cold days.

There's no real evidence that this tractor has ever derated.

 

[MossRoad]

Unless your absolutely sick over it not working properly (In the tune of $6k Sick...). $50 Katz Block Heater...... Problem solved.

He already said he does not have a place to plug it in.

 

[jacspath]

Don't forget that every time a piston cycles, it severly compresses the fuel/air mix which heats it a lot [converting energy from the starter into heat]. If your battery is in good enough shape it should crank enough rotations to do the same work as the glo plug. I no longer use a block heater. In sub zero temps I just crank it for about 10 sec. Let it warm the metal [from the heated fuel/air mix] for a few seconds and crank her again. It usually takes 3-4 such cycles and a cylinder catches and away we go. Once the engine is warm it takes a long time for it to cool enough [if I turn it off in the field for some reason] to have to run such cycles again. It will kick right over if I restart within 30 minutes.

 

[MossRoad]

 

[Syncro]

I had an l-35 with automatic glow plugs. They never worked right so I hard wired a spring loaded toggle switch and mounted it in an easy to reach location by the starter key. Being spring loaded I could never forget it in the "on" position. It was an easy fix and worked faithfully until I sold the tractor a few years ago. BTW that l-35 was one of the best Kubota tractors I have ever owned.

 

[MHarryE]

You have both a M135X and M126X. Same ECU. Do the glow plugs work okay on the M126X? I had a M135GX, complained about harsh shift and they changed everything including the ECM. It was blank, needed initial flash to match the tractor. Assumed the 2 Grand X models with the 6.1 liter engine had the same ECM until flashed. I am thinking of ways to exchange some components between the 2 as a way to troubleshoot.

 

[northcreek2624]

Why not a block heater ?

 

[shadowm77]

has it got a block heater had an old massey 165 it did not matter how cold it was plug it in for 15-30 min fired right it had no glow plugs