Pdf regen on l3901

[fried1765]

I think you are the one missing the point.

We are talking about the operating characteristics of engines equipped with DPF and catalytic converters. What you may or may not ever own is of zero consequence.

A forced regen on those engines runs for 10 plus minutes at WOT and very elevated EGT. Raw fuel is introduced into the exhaust stream to aid in burning off soot and contributes to fuel contamination of the engine oil. The frequency of that process has to be considered in any discussion of comparative service life.

Increasing the operating speed of the engine from 1800 to 2400 RPM is going to add some incremental increase in sliding wear. It also reduces the frequency of active regen by a factor of 2X or more. That reduction in regen cyclez is very significant and could quite easily offset the reduced wear associated with the slower operating speed. Its also important to remember that the higher operating speed improves DPF performance and service life. Like it or not its part of these engines.

I will reiterate - the only way to know how those competing factors balance out would be controlled testing - e.g. an engine test stand or fleet testing.

My gut says the increase in sliding wear associated with an added 600 engine RPM is relatively insignificant compared to the increased wear and contaminatuon associated with overly frequent regens.

Unlike you I own a DPF equipped tractor and I have observed first hand how mildly increasing engine RPM greatly reduces the frquency of active regens. Thats why I generally operate my DPF equipped tractor close to 2400 engine (540 PTO) RPM regardless of the job I am doing.

If you can provide some reliable test data demonstrating I am off base in that belief I would certainly be interested.

Dan

Your claim is therefore that, a DPF tractor operated at 2400RPM will have engine longevity equal to that of a like tractor operated at 1800 RPM.
Engines operated at 2400 rpm with DPF, have the same metallurgical wear characteristics as those same engine models operated at 600 rpm less?
The number of revolutions a DPF engine makes has no noticeable effect on engine wear/life?
Seems like magic!
Wondering what Hagrid thinks about this?

 

[North Idaho Wolfman]

So... help me understand this....
Pistons/rods/crank, etc., running at 1800 RPM (or less) wear ("not hurt") at exactly the same rate as those running at 2400 RPM?

Actually Yes, Kubota diesel engines have less wear when they are run at higher operating RPM'S, it less of a violent combustion, and enertia does a lot of work.
The lubrication systems are also designed to work better at higher oil flow rates.

 

[TheOldHokie]

Your claim is therefore that, a DPF tractor operated at 2400RPM will have engine longevity equal to that of a like tractor operated at 1800 RPM.
Engines operated at 2400 rpm with DPF, have the same metallurgical wear characteristics as those same engine models operated at 600 rpm less?
The number of revolutions a DPF engine makes has no noticeable effect on engine life?
Seems like magic!
Wondering what Hagrid thinks about this?

You seem to be having problems with simple logic.

Number of revolutions is one factor in wear. More revolutions means more wear.

Number of DPF cycles is another factor in wear. Fewer cycles means less wear

So if I increase revolutions by 600 RPM and in the process cut regens in half does total wear go up or down?

I told you what I think and why. I hesitate to put words in Hagrid's mouth but he is clearly of an empirical mind. I think he would agree with my position that the only way to know is controlled testing and that it is also likely engine dependent.

Sliding wear aside I am quite sure decreasing regens will extend the lIfe of the DPF and catalytic converter. Since those are very expensive components and most of my usage is an L3901 doing mowIng and loader work that requires 2000+ RPM anyway the choice is even easier.

Dan

 

[Fido Farms]

Just for some more info on regen and operating rpm check out this video John Deere has. It should help clear up the rpm/dpf regen times maybe.

 

[fried1765]

You seem to be having problems with simple logic.

Number of revolutions is one factor in wear. More revolutions means more wear.

Number of DPF cycles is another factor in wear. Fewer cycles means less wear

So if I increase revolutions by 600 RPM and in the process cut regens in half does total wear go up or down?

I told you what I think and why. I hesitate to put words in Hagrid's mouth but he is clearly of an empirical mind. I think he would agree with my position that the only way to know is controlled testing and that it is also likely engine dependent.

Sliding wear aside I am quite sure decreasing regens will extend the lIfe of the DPF and catalytic converter. Since those are very expensive components and most of my usage is an L3901 doing mowIng and loader work that requires 2000+ RPM anyway the choice is even easier.

Dan

Got it!
My "problems with simple logic" are resolved.
Lesson learned!
Diesel engines with higher RPM and DPF, typically experience less wear than diesel engines operated at lower RPM, without DPF!

 

[lugbolt]

quit worrying about wear. Use it for what its' designed for, keep the maintenance up to date and frequency, and it'll be fine.

just my opinion.

and also, some are failing to remember how the regeneration is done. Electronic injectors that run the engine, inject fuel on the exhaust stroke which raises the EGT dramatically, which heats the DPF. That is your regen. Most are done this way. B3350 is different and we won't worry about that one for this discussion. Because the fuel is a lubricant, it helps reduce wear. And since on most of the electronic common rail engines, the fuel is injected into the cylinder at a time when it's not so much burned in the cylinder as it is in the particulate filter, it kind of "coats" parts, helping to reduce wear.

dpf regeneration frequency can be affected by the condition of the air filter, the condition and level of the engine lubricating oil, the condition of the fuel, operating characteristics, load, engine temperature, and a lot more but those are the majors. Air filter being #1 and oil level and condition being #2. I've seen guys put 2 stroke oil or trans fluid in their fuel thinking they're doing good, but on a dpf engine, that oil will coke the DPF and eventually plugs it. Don't do it. Keep good clean fuel in it with no additives.