How to start diagnosing crank-no-start on a kubota common rail diesel

TheOldHokie

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Takeuchi owns the right to the Kubota engines they use, so they have their own ECU and diagnostics. A Kubota dealer or Kubota industrial engine service center can not connect to them.

Takeuchi owns its engines, which are different from any others Kubota manufactures. The warranty and software are all Takeuchi's.

Their diagnostic port is also different from what Kubota Tractor and Kubota Industrial use.

.
I understood the diagnostic ports and electrical interface are different.

I thought the software was still Kubota Diagmaster with a Takeuchi specific database and Takeuchi specific access credentials. Much the same as Diagmaster with the Kubota industrial database or Diagmaster with the Kubota agricultural database.

Of course that perception is based on the pirated software and screen shots that are all over the web.

Who owns and warrants the Takeuchi engines is a different issue.

Dan
 

c5vettster

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Well, it will be interesting. The injectors should arrive today or tomorrow. I will plug them in and hope their profile matches the original ones. This also means that even if I were to rebuild the old injectors, they won't likely to work since rebuilding will change their profile. I used to rebuild mechanical injectors and simply make sure that they "pop" using a simple pressure pump-based injector tester. I can still rebuild and test the electronic injectors but calibrating them for the ECU would be a different matter.
 

TheOldHokie

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Well, it will be interesting. The injectors should arrive today or tomorrow. I will plug them in and hope their profile matches the original ones. This also means that even if I were to rebuild the old injectors, they won't likely to work since rebuilding will change their profile. I used to rebuild mechanical injectors and simply make sure that they "pop" using a simple pressure pump-based injector tester. I can still rebuild and test the electronic injectors but calibrating them for the ECU would be a different matter.
Common rail injectors "pop" as many as 5 or 6 times per ignition event. I think its safe to say the new injectors will not match the old ones. How much the mismatch degrades engine performance is a big question.

Dan
 

c5vettster

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lot of kubota stuff
Aug 30, 2022
35
6
8
Maryland
Common rail injectors "pop" as many as 5 or 6 times per ignition event. I think its safe to say the new injectors will not match the old ones. How much the mismatch degrades engine performance is a big question.

Dan
One would think that the ECU has adaptive abilities to accomodate for some range in injectors? One supposes that any injector spray pattern changes with time, fuel quality, ambient temperature, etc. These are industrial engines and are designed to perform in the toughest conditions.
 

TheOldHokie

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One would think that the ECU has adaptive abilities to accomodate for some range in injectors? One supposes that any injector spray pattern changes with time, fuel quality, ambient temperature, etc. These are industrial engines and are designed to perform in the toughest conditions.
Sure. The ECU gets its baseline adaptive data via coding. Thats what the code on the individual injectors tells the ECU. The ECU is not going to "learn" that on its own.

Dan
 

c5vettster

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lot of kubota stuff
Aug 30, 2022
35
6
8
Maryland
One would think that the ECU has adaptive abilities to accomodate for some range in injectors? One supposes that any injector spray pattern changes with time, fuel quality, ambient temperature, etc. These are industrial engines and are designed to perform in the toughest conditions.
Well, I may have to buy a bullet and bite that diagnostic software so to speak. It is amazing how few shops know/have the ability to work on these smaller diesels.
 

TheOldHokie

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Well, I may have to buy a bullet and bite that diagnostic software so to speak. It is amazing how few shops know/have the ability to work on these smaller diesels.
There is more to it than writing a check. If it were that easy lots of people would bite the bullet.

My understanding iz you also have to demonstrate a "need" and attend annual training and certification classes. Licenses are then renewed annually (another check).

Dan