Status of B3350 Regen Issue?

[rjcorazza]

Why does the dpf regeneration pull a high electrical load? I was of the belief that the process injects diesel into the canister itself to increase temps during regeneration.
Is it the monitors and various controls that increase the electrical demands, or is there an electric heating element involved?


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[SDT]

Why does the dpf regeneration pull a high electrical load? I was of the belief that the process injects diesel into the canister itself to increase temps during regeneration.
Is it the monitors and various controls that increase the electrical demands, or is there an electric heating element involved?


Sent from my iPad using Tapatalk Pro

It doesn't, though the load is increased somewhat during regen.

Early 3350 ROPS tractors were equipped with a lower output alternator than have been cab tractors since the outset. Apparently, this was marginal as at some time Kubota decided to install the higher output alternator used on cab tractors on the ROPS models as well. Not sure if they have retrofitted early ROPS tractors with the standard alternator to the cab version, but doubt it.

SDT

 

[SDT]

The tech did mention that the regen system does create a large electrical load and that other accessories could pull enough to cause an issue. The higher output alternator is one of the updates Kubota installed on earlier models to address this. Newer models have it standard. Not sure of when they began making it standard.

As far as creating a checklist to help others to address how to be proactive to prevent problems and reactive on how to resolve them once they occur, I may do that if in fact what the tech told me works. Time will tell.

To be honest if these tractors are this sensitive to cold, water, etc. I am of the belief it should be Kubota that is coming up with the detailed instructions. Their engineers have shared the knowledge with the techs but there seems to be a disconnect where the knowledge isn't making it to the customers in an effective way. Is that due to a failure of dealers to communicate it or is it because the system is so complex and there are so many variables that no matter how much communication there is or how it is done the end user will inevitably have a problem.

I have seen this many times where a sub-system on an otherwise good product doesn't perform well in certain environments and situations. The manufacturer tries to resolve it with retrofits and many times they do improve it, but the problem is inherent in the design and to redesign the entire sub-system is not cost effective or in some cases even possible.

These retrofits can take time (and $$) and perhaps most of all a slice of humble pie, since re-engineering what your highly paid engineers already said would work doesn't. It also buys them time as well (which works in their favor).

The manufacturer then stands by their product and says they resolved the issue with the retrofits over the past XX years. If there are some end users who still experience problems it is their fault and they can upgrade to the newest model that was just introduced.

Not the best outcome for an end user, but a bad product is inevitable to occur a few times in the course of a manufacturers history. Especially a company as old as Kubota. How well they handle the fallout in the form of miffed customers and reputation is usually the indicator of a companies management belief system.

I think Kubota has done everything they feel they should have done and are now just trying to hedge their losses. I understand and have seen it before.

I bet they have spent more time and money on the next model to prevent this from reoccurring. Which is a good thing.

Mike



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The forthcoming replacement LX3310 model uses common rail fuel injection as do other Kubota models. This should make regen procedures as trouble free as is such on other models.

The 3350 and certain dedicated mowers using the same engine is unique in using a mechanically injected engine, rendering the regen system different in just about all respects. It is my belief that this system cannot be made reliable in the intermediate or long term. Whether it can be made so in the short term remains to be seen.

 

[sheepfarmer]

Why does the dpf regeneration pull a high electrical load? I was of the belief that the process injects diesel into the canister itself to increase temps during regeneration.
Is it the monitors and various controls that increase the electrical demands, or is there an electric heating element involved?


Sent from my iPad using Tapatalk Pro

My understanding of the 3350 process (not present in the L tractors) is that there are two processes " a heater glow" and a " burner glow" to control the temperature of the gases entering the DOC. The hot gases from the reformer then go into the dpf filter to burn off the soot.

So my interpretation is yes there is an electrical demand.

 

[SDT]

My understanding of the 3350 process (not present in the L tractors) is that there are two processes " a heater glow" and a " burner glow" to control the temperature of the gases entering the DOC. The hot gases from the reformer then go into the dpf filter to burn off the soot.

So my interpretation is yes there is an electrical demand.

Indeed, but nominal.

SDT

 

[sheepfarmer]

Indeed, but nominal.

SDT

Perhaps nominal, but something in the 3350 process made Kubota add this sentence to that owner's manual that is not in the 3560 manual:

"IMPORTANT
When ambient temperature is so low or when working with such extraordinary use of electricity that the regeneration conditions are not satisfied, the regeneration indicator starts flashing.

If the regeneration indicator turns on and then starts to flash, etc etc."

 

[SDT]

Perhaps nominal, but something in the 3350 process made Kubota add this sentence to that owner's manual that is not in the 3560 manual:

"IMPORTANT
When ambient temperature is so low or when working with such extraordinary use of electricity that the regeneration conditions are not satisfied, the regeneration indicator starts flashing.

If the regeneration indicator turns on and then starts to flash, etc etc."

Agreed vis a vis early models.

I can envision rare circumstances when electrical loads might exceed alternator output at whatever engine RPM during (or not during) regeneration operations, especially in situations when the battery is not fully charged. I can also understand why Kubota might have decided to institute an engineering change replacing the "standard" alternator with the "cab" alternator so as to eliminate such potential issues.

That said, low voltage is NOT the cause of the overwhelming majority of regen issues with the B3350 and other machines using the same engine.

SDT

 

[joelx]

Agreed vis a vis early models.

I can envision rare circumstances when electrical loads might exceed alternator output at whatever engine RPM during (or not during) regeneration operations, especially in situations when the battery is not fully charged. I can also understand why Kubota might have decided to institute an engineering change replacing the "standard" alternator with the "cab" alternator so as to eliminate such potential issues.

That said, low voltage is NOT the cause of the overwhelming majority of regen issues with the B3350 and other machines using the same engine.

SDT

I solved the Kubota 3350 Regen issue, at least for myself. Try this:

I have had tons of issues with the terrible DPF system on my Kubota 3350b. The Regen light would come on and would not go off. Eventually it would demand parked regen. That would fail too and it would beep once a second until I took it to the dealer.



I noticed this did not happen in the summer, just in the winter and spring and fall. The dealer said that when he was testing it, it was not getting hot enough. I suggested putting a blanket on it, he ignored that.



I started having the issue again this week. I went through the process of failed automatic Regen, failed parked regen, and finally tried my blanket idea.



With one heavy moving blanket covering the whole engine and radiator but not the exhaust, the temperature never went above three bars. With two blankets, I was able to get it to 4 bars. With three blankets, I got it to 6 bars and successfully ran the Regen and the errors are all cleared now.



I guess the engine just is too cold by default to run the Regen.

Kubota 3350b Regen DPF Issues SOLUTION!

I have had tons of issues with the terrible DPF system on my Kubota 3350b. The Regen light would come on and would not go off. Eventually it would demand parked regen. That would fail too and it would beep once a second until I took it to the dealer.I noticed this did not happen

joelx.com