Kubota Interim Tier IV Motor Oils

[rScotty]

Exhaust Gas Recirculation (EGR) is often misunderstood.
Exhaust is introduced into the combustion chamber,which dilutes the oxygen level in the chamber.
This results in a lower combustion chamber temperature,thereby reducing NOx emissions.

Thank you for participating. What is it that you think is misunderstood? How to explain it better?

Let me add that the EGR gas is first cooled by engine coolant in a heat exchanger, and then mixed with more heated turbo-pressurized air in the intake manifold before going on to the combustion chamber.
So although lack of oxygen reduces combustion temperatures, the intake air is still heated above ambient.
Retarding the timing further reduces combustion temperatures.

Lower temperatures plus the lack of oxygen reduces NOx emissions, but increases the soot emissions.

In a nutshell, the increased soot is the problem with using EGR to meet Interim Tier IV regulations. The whole Interim regulations is a poorly designed stopgap that met the regulations but missed the point.

Some of us with Interim engines who would like to reduce the soot as well. Anyone who wants please jump in. It would be better for the operator, the world, and of course it would be better for the engines. Soot is not only a poison, it is abrasive.
Thanks,
rScotty

 

[rScotty]

How do you disable the EGR? Thoughts on adjusting the timing?

There is a rather large company in a nearby rural county that adjusts diesel big trucks, big equipment, ag etc to improve performance, economy and longevity. Since they do on road diesels I’m sure they do what’s legal. Not your teenager with diesel pickup hot rod shop.

My old M5030 could bush hog with about half the fuel of my M59. So if one could improve the power and economy would be nice.

Hey Smokey,
Do you have an M59 workshop manual? If so, you'll have noticed that each mechanical system has a "how does it work" section followed by how to fix it.

The EGR section in the engine chapter of the workshop manual is particularly good.

The EGR assembly is a pressure-activated bellows which opens an EGR valve allowing the turbo to force a bit of cooled exhaust into the intake manifold. But the EGR doesn't open until a thermostat at the front of the engine senses that the coolant is above 149 deg.F. At temperature, that thermostat opens to allows a bit of pressure back to work that bellows in the EGR assembly which then opens the EGR valve. The bellows activating pressure is conveyed back to the EGR assembly by a quarter inch diameter rubber hose running back from the thermostat on the front of the engine. Line "B" on page 1-M3 in the manual.

If you simply put a valve in that hose you can turn the EGR on/off as desired.
Since I'm at 7000 feet, and my engine normally runs cool... and I've suspected that the EGR may not function as designed on our M59.
Eventually I plan to add a solenoid valve so that I can turn the EGR on and off from the dash. And may put some pressure gauges and a real coolant temperature gauge there as well.

Yes, the M59 Interim engine is a fuel hog. Remarkably so. Ours also uses a surprising amount of fuel compared to older engines. I suspect that is because of the timing, but I need to know a little more before thinking about changing that. From the workshop manual it sounds to be fairly easy to do.

Right now the easy thing for the soot in the engine is to change the oil more frequently....that's what started this thread.
And maybe someday a vertical exhaust for my own enjoyment.
rScotty

 

[jaydee325]

although I wish the initial low temperature viscosity was lower for cold weather. I compensate for that by never starting up below 30F without having run the block heater for a hour or more.

Multi-viscosity oils are another often misunderstood area.

The W (as in 10W-40 for example) does not mean it's 10 weight at low temperature. The W stands for winter. In multi viscosity oils, such as 10W-40, the oil flows like a 10 weight oil at 32 deg F and has the characteristics of a 40 weight oil at 212 deg F.

Here is a link to a brief description.

Below is the viscosity chart for my LS R3039H. SAE 15W-40 is fine from -5 deg F to 104 deg F.

 

[Smokeydog]

Appreciate your explanation. Yes have a shop manual and enjoy learning. Like doing my own customization to make a better tool but know my limitations and seek more knowledgeable experts.

Some of my old diesels had the cleanest oil and logged 1,000s of hours with minimum maintenance requirements. Also very fuel efficient.

 

[MHarryE]

Here is the API (American Petroleum Institute) word on CK-4 oils:

API CK-4 and FA-4 Background
These new oil standards were developed to better protect new and older engines, improve engine oil performance, and help engine manufacturers meet 2017 government emissions standards. CK-4 and FA-4 improve upon existing standards by providing enhanced protection against oil oxidation and engine wear, particulate filter blocking, piston deposits, and degradation of low- and high-temperature properties. The new categories are the result of several years of collaboration between engine manufacturers, API’s Lubricants Group, the Truck & Engine Manufacturers Association (EMA), and the American Chemistry Council (ACC).

An important issue for fleets, truck and ag, is increasing oil change intervals. I grew up on a farm, worked with engines throughout my engineering career, and bought my first tractor for retirement in 2002 (many years ahead of retiring). With the changes in emissions requirements and oil change intervals, I hear all kinds of bad about new compared to old. Personally, I like the 500 hour oil change interval on my 2017 tractor vs 150 hours on my Cummins equipped 1992 combine. Also its surprising how quickly my combine can empty its 150 gallon tank vs my tractor with its 90 gallon tank - their engine power is about equal. So to see what the fuel economy difference is between the most popular ag tractor when I left the farm (4020 JD) and an equivalent HP Deere from today. Nebraska test - John Deere 4020 PTO HP 91 HP max, 14.20 HP-hr/gal at that power. John Deere 5090R 92 HP max, 18.36 HP-hr/gal. So about a 30% improvement in efficiency. I have a Kubota, not as efficient as a JD but still 16.04 so a nice improvement over the old diesels.

But your question is using new rated oils, and API insists new oils are backward compatible. So CK-4 will work fine in your interim.

I had a Kubota M135GX with Interim T4 engine. Ironically it was more efficient 16.86 HP-hr/gal compared to my M7 - I assume due to all the extra parasitic goodies on my M7.

 

[rScotty]

....SNIP....
I had a Kubota M135GX with Interim T4 engine. Ironically it was more efficient 16.86 HP-hr/gal compared to my M7 - I assume due to all the extra parasitic goodies on my M7.

Hellow MHarryE, nice to have you aboard. I realize the Interim engines are no longer sold, but I suspect they are going to be around for quite a while so I'd like to see them improved if we can.

Did your M135GX have EGR? How was it for soot?
Since your operation sound fairly large judging by the tractors, did you measure the HP-hr/gal or are those mfg. specs?
rScotty

 

[jaydee325]

To be clear here, FA-4 diesel oil is only recommended for a very specific group of diesel engines, 2017 and later and only if the OEM recommends it. It is not backward compatible with any previous API diesel oils.

This article explains it.

 

[number two]

Maybe not of interest here,but 2 cycle Detroit Diesel engines still require CF-2 straight weight oil.
Had 6 of them back in the old days-fun times!

 

[5030]

I have a 2009 pre-tier 4 Kubota M6040. From my Op Manual - -
- Use engine oil with API classification CD, CE or CF
- temp ranges - from above 77F to below 32F - 10W-30 or 15W-40
- they speak of using CF-4 and CG-4 with low sulfur diesel - if used with high sulfur diesel - oil change at more frequent interval.

I use Shell Rotella T4 15W-40. Far exceeds these 12 year old requirements.

I use T6 myself in both my M's and a shot of Archoil Nano Borate additive too.