I’m looking for some help to lower the idle speed on a kubota v2403 that was used in a Lincoln welding machine. It has a low idle and high idle feature. Low idle rpm is 1400. High idle rpm ranges from 1450-1600 controlled by a potentiometer. The set screws located on the injection do not move when rpms are changed. I believe it all controlled by the fuel shut off solenoid. Any help would be much appreciated. Thank you.
Kubota v2403 idle adjustment
- Thread starter CalebHardy
- Start date
Can anyone point me in direction to find the help? Possible dealership or shop that is familiar with this style of engine. CA shops do not want to change it in fear of emissions even though it’s used in other applications at lower RPM’s.
I believe it’s by the fuel shut off solenoid. Which is controlled by the ECU. There is also a potentiometer that allows you allow you to raise and lower your rpm. (1450-1600rpm)
The 2 screws that are locked by the locking wire are used to adjust low speed idle and high speed or rated rpm. Are you changing the application of this engine or do you just want it to idle at a lower rpm?
If you do adjust the idle and rated rpm you will have to install some sort of control to the governor input lever.
If you do adjust the idle and rated rpm you will have to install some sort of control to the governor input lever.
I would like it to idle at a lower rpm. I don’t know if you can see it in the picture, the bracket that set screws hit against are not independent. There is a weld connecting the two. Also as the rpms change the set screws and brackets they push against never move.
Strange. I’ve never seen that, I’ve also never worked on a Kubota powered genny. Sorry I can’t help. Will stay along for the learning though.
A nearly fixed operating range is typical for the prime mover in a genset but speed control via a fuel shutoff solenoid is a new one to me.
I have a 40KW standby generator powered by a Mitsubishi 3.3L turbo diesel which starts and runs at 1800 RPM. It has fixed stops like the Kubota pictured but they are set to allow a slight amount of movement. The pump mechanical governor is set for 1800 RPM but the controller for the genset exercises a small amount of control over the governor lever to maintain precise speed control to keep the output frequency at 60 hz.
For the engine in question, it would be interesting to see how the ECM reacts if the mechanical stop on the governor is adjusted to allow a lower idle speed; my guess is it will try to correct back into the range it expects so reduced idle on this set may not be compatible with ECM programming.
Rodger
I have a 40KW standby generator powered by a Mitsubishi 3.3L turbo diesel which starts and runs at 1800 RPM. It has fixed stops like the Kubota pictured but they are set to allow a slight amount of movement. The pump mechanical governor is set for 1800 RPM but the controller for the genset exercises a small amount of control over the governor lever to maintain precise speed control to keep the output frequency at 60 hz.
For the engine in question, it would be interesting to see how the ECM reacts if the mechanical stop on the governor is adjusted to allow a lower idle speed; my guess is it will try to correct back into the range it expects so reduced idle on this set may not be compatible with ECM programming.
Rodger
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I was afraid of that…..do know what type of program they run j1939 or whatever it may be? Or if anyone knows of someone that is able to reprogram?
Hopefully someone who knows that ECM will chime in. If it is using an input fuel restriction to the pump to control speed it might set an error code if the RPM is below its target level with the fuel flow wide open. But at least this shouldn't create any injection pump/engine damage issues. I would be more concerned if you were trying to raise speed above what the ECM expects because it might try restricting fuel flow to the point that the injection pump is pulling more of a vacuum than it can safely do without long-term damage.
Rodger
since this is a welding machine I would like idle at 800-900 when there is a load it will be in the range of 1450-1600. You are correct in it was designed to run that way for EPA reasons. Performance should remain the same as the v2403 with the same injectors bore and stroke are in other pieces of equipment with a wider range of rpms and when it’s under load it will be in the acceptable rpm range (1450-1600)
Is this welder a full Tier IV setup with DPF? If so, the low idle will be an issue with DPF loading due to it running too cool. Otherwise if it isn't a Tier IV with DPF then it won't meet emissions but it shouldn't hurt the system.
To get any major difference between no load idle and loaded operating RPM conditions, the lower RPM stop on the governor will have to be adjusted AND you will need an electro-mechanical actuator to pop the governor to the rated load RPM under load. This could be complex with your setup since it has an ECM controlling the engine but unlike a lot of Tier IV setups, it doesn't use the ECM to control speed directly via using a common rail with electronically controlled injectors.
Rodger
To get any major difference between no load idle and loaded operating RPM conditions, the lower RPM stop on the governor will have to be adjusted AND you will need an electro-mechanical actuator to pop the governor to the rated load RPM under load. This could be complex with your setup since it has an ECM controlling the engine but unlike a lot of Tier IV setups, it doesn't use the ECM to control speed directly via using a common rail with electronically controlled injectors.
Rodger
EPA does not dictate that parameter. It more likely has to do with speed droop when you load the engine such as striking an arc. All the Lincoln welders I have used seem to run similarly. If the engine rpm droops to much it is slow to recover and start of the arc is poor.
The engine does not run a dpf. The EPA did dictate the RPM range according to Lincoln. I just finished adapting an old welding machine with an f162 to a V2203 without an ECU and it has no issues at low idle 800rpm and high idle at 1500rpm. So as the engine sits 1400 low idle high idle 1450-1600. I am just wanting to take the 1400rpm low idle setting down to 800-900rpm.