DPF v. No DPF

[Allan M]

I own a U55-4 Kubota Excavator and recently sold my first compact tractor and replaced it with a Kubota LX3310. Having read many forum threads here and elsewhere and watching a number of YouTube videos there seems to be a lot of avoidance around more than 26HP (the cut-off for diesel regen). I wanted more PTO hp so the LX3310 is 31hp engine and 27hp at the PTO. I haven't found the U55 regen a big deal. I haven't run the LX3310 long enough for a regen cycle but here is my initial impression: 1) a four cylinder engine runs smoother than a 3 cylinder. Like comparing my V8 truck to a V6 truck. 2) I keep my tractor in a 600 sq ft barn. Starting my former 3 cylinder 23hp tractor would fill the barn with black diesel soot. Not so with the 31hp engine with DPF. 3) I can run this tractor in midrange gear up my mountain roads with no trouble or bogging down on the HST transmission. I had to run in low gear with my former tractor. 4) The extra PTO power is great for running my BearCat Chipper. Doesn't bog down. 4) I can grade uphill no problem as long as I have traction. 5) The tractor runs cleaner. I'm not breathing exhaust fumes that can choke me in the wrong wind direction. So, while I get that my DPF system has more expensive parts and required maintenance, I see only upside here in my situation. I'd be interested in thoughts from others on this topic and their perspectives. Thanks. Note pic: Get a new tractor and get the girls! Just kidding. My son's girlfriends.

 

[funwithfuel]

I appreciate emissions apparatus for what they are. Where I, and probably most other folks, find issue is when a sensor is out of range, it derates and shuts you down. In the beginning, there were a lot of people treating symptoms vs root causes. This put a lot of mom-n-pops out of business. Even now, regular maintenance is a huge expense. Most DPF require cleaning between 4 & 4.5k hours. You either have downtime waiting for a service to clean yours or you pay significantly higher costs for reman exchange where you may receive a compromised DPF. At the end of the day, they have their place. Just don't appreciate how it was implemented.

 

[Allan M]

Hey funwithfuel: Thanks for the response and education. I have very limited experience with DPF. My excavator which I've run about 1000 hrs cutting trails in hilly terrain has only DPF cycled 4 times that I can remember. I can still work during the cycle...but if I didn't have my thumb activated, I'd have to wait until after the cycle (maybe 15 minutes) to do so--and that was aggravating. I wonder if the DPF technology is evolving where it isn't a mechanical nightmare any more on newer machines. I suspect on bigger equipment it's also a very different ballgame. Again, thanks. A

 

[Birken Vogt]

It is a whole different engine between 25+ hp DPF and sub 25 HP non DPF. The DPF engine is full of electronics and garbage while the non DPF engine should be most/all mechanical. Electronics require a dealer of questionable competence to work on sometimes, mechanical anybody can work on it.

 

[Allan M]

I hear you Vogt. I guess one makes trades. If you want the hp then you step into a more complicated mechanical world. I'm hoping my dealer continues to be a good one. During my purchase I had hydraulics added to the rear in order to control a box scraper with curl and side to side angle; and 3rd function added to the front for a grapple. After about 2.5 hrs of run time I blew the seals on the hydraulic valve block on the rear hydraulics--fluid showering everywhere. It turned out that when the mechanic added the rear hydraulics the valve block wasn't torqued sufficiently and blew while I was grading. The good news is that I got an apology from the dealer and a mobile mechanic was on site to remedy the situation in about 2 hrs. I'll keep my fingers crossed on the DPF function.

 

[BC Placer gold]

We had a brand new Kubota KX-040 with dpf (no def, under threshold hp).

The machine sat on an elevated pad feeding loose pay onto a double screen deck wash plant (1/4 yard bucket). Feed rate of 25 yards/h. Problem was…the machine was never worked hard enough in this application. Re-gen’s were every 20-25 hours. By the time we sold the machine re-gens were as often as every 8-10 hours (fall/early winter operation worse)

We ended up selling machine at 700h. Really liked the Kubota ; smooth/powerful/fast hydraulics. Just became concerned about possible de-rate issues; the remote location of the mine site means a 10 h round trip for a mechanic with a laptop…

Currently running a pre-emission (2011) Deere 50d. Much better suited to our operation.

 

[Swetz]

I am not sure how bobcat it doing it, but they are selling their stuff without the regen/def stuff. My neighbor bought a new Excavator and CTL this year, and neither have the regen/def stuff. . They do have a DOC.

Below is a thread that is a bit old, but talks to this subject.

New Bobcats, No DPF, no DEF and a bobcat diesel engine. Thoughts and experiences?

I am about to pull the trigger on a new machine, comparing a cat 262D, 242D and Bobcat 630 & 650. I'm leaning toward the 630 and like that they don't have a DPF or DEF to deal with but am leary on a whole new engine design without knowing it's been put to the test. Does anyone have any good...

www.heavyequipmentforums.com

 

[franklin2]

Not sure if it's relevant or not, but I have a 09 F350 with the dreaded 6.4 with the DPF system on it at work. For years each time the screen on the dash told me it was cleaning the filter, if I was in a slower mph area I would pull it down into 3rd gear. If I was in a higher mph zone I would put it in tow/haul mode. It's fully loaded with junk and I run it hard.

I have never had any clogging issues with the filter. In fact, after a regen now I will get a check engine light for a little while, and then it goes away. It is a regen fault and then it clears itself. I also noticed I get black smoke out of the tailpipe when I floor it. I did some research and from what I can learn, this means the DPF filter is burnt out. Great I say, it runs like a top, lots of power, 153,000 miles.

Moral of my story; Run it like you stole it, and you will not have a clogged exhaust filter.

 

[Birken Vogt]

I am not sure how bobcat it doing it, but they are selling their stuff without the regen/def stuff. My neighbor bought a new Excavator and CTL this year, and neither have the regen/def stuff. . They do have a DOC.

Below is a thread that is a bit old, but talks to this subject.

New Bobcats, No DPF, no DEF and a bobcat diesel engine. Thoughts and experiences?

I am about to pull the trigger on a new machine, comparing a cat 262D, 242D and Bobcat 630 & 650. I'm leaning toward the 630 and like that they don't have a DPF or DEF to deal with but am leary on a whole new engine design without knowing it's been put to the test. Does anyone have any good...

www.heavyequipmentforums.com

There are certain tricks that they are doing on under 50 HP engines to squeak by without DPF. In fact I thought Kubota was one of them. Isuzu also. Just a highly efficient DOC. Did we get it right, this one actually uses DPF+SCR?