My 3301 regened for the first time this weekend at 20 hours almost exactly. I tend to keep the rpm's up between 2000 and pto mark. All the kubota mechanics i've spoken with have said that they're made to be run high. Has far as the regen is concerned, I started mine up to move it out of the garage so i could rearrange some things. after idling outside for about 10 minutes i jump on it to bring it back in and the regen light is flashing along with the increase rpm light. I had to put the rpm's over the pto line to get the increase rpm light to go out. I think that was only because it was idling though. after about 2 minutes i started backing the throttle off to about 2200 rpms and the increase rpm light never came back on. smelled weird and sounded kind of funny but after about 20 minutes the regen light went out. I'd prefer the tractor not have to do this but it worked fine while it was in regen. I got a little unplanned seat time.
I'd like to know if theres a way that would make it regen on it's own while parked idling like that. I thought it would but I also didn't have the parking break on and probably left it in gear. Does anyone know if in the situation i described, had I have had the parking break engaged and had the tractor in neutral, would it have increased the rpms on its own and regened?
I have had the same questions, which I have posed to Kubota's "customer satisfaction" folks, and finally found some answers in the shop manual which I just received. So assuming the 3301 runs the same as the 3560 as far as the regen programming, here is what I think:
1. You can't trigger a regen cycle whenever you want. I suggested to them they change their programming to allow it , since it would be more convenient if you could when the dpf was getting full and you had 20 min to finish what you were doing. Right now you can't do an auto regen unless the meter reaches 100% and the light starts to blink. You can't do what they call a parked regen until the dpf reaches what tney call level 2.
So in the situation you describe it would not have gone into parked regen mode and increased the rpm by itself. Or at least I don't think so. There are too many things you have to set to permit it to do that.
2. You can park it and do the regen in the autoregen mode, you don't have to find work to do, you just have to increase rpm until the light goes off.
3. It is not a good idea to back off the rpm in case you interrupt the regen since there is some chance of diesel draining into the oil if it is not burned.
4. There are at least 4 levels possible in this process, there is a table in the owner's manual that helps to explain this. It gets tricky if someone misses the light flashing and the engine ECU progresses into stages 2 or 3 without being given the opportunity to regen.
On mine I think the easiest thing is to leave the dash display to show the dpf particle level, and then when it gets up to 99% to make sure it is set already to auto regen, and then when the light comes on, up the rpm and let it do its thing.
As far as the idling issue is concerned, they recommended to me to shut it off when not needed. These engines start easily, so no reason to leave it sit for 10 minutes at dead idle. If warming up in bitterly cold weather cold weather they recommend half maximum rpm, for mine 1350 rpm, for the specified length of time before working the hydraulics.
Hope this makes sense ok. It took me several runs through the manual before I understood mine. It is not very clearly written. Holler if not.