# Kubota V2203DI Generator RPM Issues



## Rahr24 (Apr 30, 2021)

First post here. I have a V2203DI kubota diesel with a variable 50/60hz generator. When working correctly, they run at 50hz (1500rpm) in low load operator and 60hz (1800rpm) in high load. One of the ones I'm working on starts up at 60hz no matter what. It has a voltage controller that provides a signal to the electronic governor. Normally if one of those is bad, it will run at 50hz no matter because thats standard, so I know that's not the issue (switched it out just to make sure). There is an engine speed sensor that sends signal to the the EG, checked the pins on that into the EG and they have continuity, also replaced the speed sensor just to verify its working correctly, still starts up at 60hz. Switched out the EG with one from a unit that is working correctly, same problem exist.

One thing I do not quite understand is how these electronic governors work with the speed sensor and the mechanical injection pump. How do they get the signal and regulate the fuel on the injection pump to maintain rpm from load? I haven't taken out these injection pumps before to look at the internal mechanical governor (fuel solenoid too). Maybe somebody could help me explain how these work as I figured most basic diesel generators work close to the same. I'm guessing that the mechanical governor or pump has an issue? No smoke or anything on startup although it does take a bit to turn over (probably just from standard hour accumulation). Once it does start, it runs just fine. Just need to get the voltage down to 50hz where it is supposed to be during startup. Any help would be greatly appreciated


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## tabora (Sep 6, 2018)

Rahr24 said:


> 50hz (1500rpm) in low load operator and 60hz (1800rpm)


I would think that the 50hz (1500rpm) setting would be for overseas use like in Japan or the UK, while 60hz (1800rpm) would be for use in the US.


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## iowagold (Jan 22, 2020)

most of these units are servo controlled.
so they have a sense setup for what ever the parameters for sensing
then use the servo for the fuel control on the injection pump..
that is if it is mechanical injection.
speed as hz

the new tier 4 and tier 5 setups are full computer controlled injection.
better emissions and better on fuel...
but you need a special computer setup to work on them.


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## Rahr24 (Apr 30, 2021)

iowagold said:


> most of these units are servo controlled.
> so they have a sense setup for what ever the parameters for sensing
> then use the servo for the fuel control on the injection pump..
> that is if it is mechanical injection.
> ...


Yes you are correct. I figured it out. I always thought that these shut off solenoids only shut off the engine, not true. The electronic governor sends a varying voltage to the solenoid and that changes the rack position on the pump. Makes much more sense now. Speed sensor is used to compare current rpm to governor set point, governor sends signal to output (solenoid) to balance the rpm from load.

Change out the shut off solenoid, good to go. Just sticking a little bit.


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## iowagold (Jan 22, 2020)

yea pesky fuel shut off sol are the weak link.
we keep spares on hand for them!
easy to swap out on most of these little units..
but in the middle of a run failure...... nice to have a spare!

same on fuel filters..
did you do a separate over sized after market water separator yet???
cool up grade!
we do that on all diesel gear in the fleet..
and check the separator for water every day when checking the engine oil.

big note some of the new JD engines now have a de rate for water in the fuel as well as a shut down.
water is hard on an diesel injection pump and injectors...
rust inside!


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