Kubota v2403 idle adjustment

lugbolt

Well-known member

Equipment
ZG127S-54
Oct 15, 2015
5,207
1,893
113
Mid, South, USA
leave it alone if you're gonna use it as a welder.

Yes emissions does play into it a little but not as much as loading of the engine via the generator. Once you strike an arc a significant load is placed on the engine; and reduction of low idle will usually result in a poor arc until the engine recovers, as said. Also, the frequency of the AC output changes unless there is an inverter involved (I don't know on your gen set). If it's strictly AC only, then yeah lower engine speed=lower frequency and vise versa. Lastly, engine vibration can also play into it; you get much below 1000 RPM on an inline-4 diesel and it's going to vibrate unless it's counterbalanced which the V2403's are not. Someone's fixing to say "my tractor doesn't"....but keep in mind that a tractor sits in a different kind of mounting system, e.g., it's mounted directly to the transmission, Kubota designed it that way which does reduce some vibration that would normally be felt by the operator. Had a customer once who had bought a used ZD 326 as I recall, the PO didn't like the idle speed so he cut the limiter off of it and reduced the idle speed way back. I don't know what the actual speed was, but it was probably 800-900 RPM. At that speed, because the engine was mounted on rubber mounts, you couldn't even read the sticker on the valve cover. Couldn't make out a lot of stuff on the engine because it vibrated so horribly. So I called Kubota directly and asked them what the spec was for low idle speed, explaining that the low idle screw was adjusted, and they told me to pound sand....they won't give you the information based on the fact that adjusting the low or high idle stop screw messes with the emissions. So I just turned it back up to where it sounded like another ZD of the same model, and sent it out after fixing the numerous other problems it had.
 

CalebHardy

New member
Lifetime Member

Equipment
Kubota v2403 Lincoln Welder
Aug 16, 2022
12
0
1
Bakersfield CA
I’ve welded with these machines for 15 years now and never experienced a problem with striking an arc with poor arc characteristic due to the rpm difference. I’ve never had an issue before with the past 4 machines I’ve owned. Everyone one of them 800-900 rpms at low idle. Also there is no AC current on this machine DC only. At 800-900 rpms on the previous build kubota v2203 (similar to the v2403) mounted on rubber mounts ran very smooth. I understand that you think I should leave it alone and I respect your opinion but im looking for help in lowering the rpm. I have adapter 3 other welding machines to the kubota engine. I have never used an engine with this type of rpm control and I’m just looking for some help.