There are many types of oil and its wrong to make any general statement about any one particular type. In most cases its the issue of getting the right technology to suit the fuel and then the limitations of the engine to accept that technology which is the issue. Additionally the political and aesthetic limitations which sometimes decide the viability of the project.

4960 is the best example but even there we found some limits within the locomotive we could not pass. There are some examples like 2100 which although being a technical failure actually teach you how to make it work properly. In some such instances these engines actually advance the technology more by proving you need to go in the opposite direction. The work in Tasmania also taught me that what was perfect for one fuel was not good for another although the general principles remained the same. Good draughting, an even and ample supply of air, limiting atomising steam and superheating, the correct type of burner and fuel heating are the main points.

I can't comment on 4014 because I am not involved. I have little doubt that she will work as an oil burner but how it will be done is as far as I am concerned a matter for UP to decide in due corse. I really don't see what speculating what they are doing serves any point at this time. The rest of the loco needs to be made fit for purpose first.

From the perspective of having the drawings for 800's/3900's/4000's, fired the 844/3985, modified the 3985 front-end and firepan, worked on 844/3985 for 5 years, been in 3977's firebox, cosmetically restored 4023, been in 52 8055's firebox as well as the footplate, 4960 footplate, modified GCRR 29 footplate, Worked with Nigel Day, read a lot of stuff, I am going to have to disagree with both of the above statements.

Diesel fuel behaves differently when used in a burner/firepan arrangement designed for a heavier fuel. A result of poor mixing with combustion air/ insufficient drafting can be the presence of pockets of cold, "tramp air" in the firebox which causes great local stresses on the firebox sheets. Typical aspects I see of sucessful diesel combustion systems are that the flameways are shorter and a great deal of emphasis is placed on earlier and turbulent admission of combustion air. One will notice the UP designs have a rather crude block of air admission tubes at the end of the flameway.

The copy approach was taken with the 4000 class at one point. In fact, one will find similar components/designs used in all the UP oil burner systems for all classes. Information on what was done is kept by those who value such things.

What was a very interesting and painful lesson for me with 3985, is the paradox of Superpower design, which is epitomized with large articulateds. Essentially, one places a much larger boiler on a locomotive chassis than it needs, with a huge firebox. The objective (for coal combustion) was to reduce the combustion rate per sq/ft of grate such that fuel carry-over (cinders) was reduced. With sufficient draft, the boiler could produce more steam that the engines could use. The problem is, to produce that draft, one needs a lot of steam flow, which is only achieved by running a long cut-off with a lot of throttle. 3985 was very difficult to fire under light loads, and as the cylinder conditions degraded (listen to early recordings vs. later ones) it became more difficult. By the time we made the Lempor/firepan changes the pistons/rings/cylinders were in poor condition, likely attributable to the lay-up fluid placed in the superheaters which continually bled-out over the winter and actually seized the engines up on more than one occasion when it sat for a while. Cylinder work or even inspection was determined to be outside of the scope of the project, which contributed to our failure. However, a major factor was also that the exhaust steam is subject to intense throttling as it travels though the small pipes and passages full of torturous turns from the cylinders to the nozzle stand of this locomotive. For a Lempor to work, it has to be the point of restriction, and with the locomotive design and condition this was achieved only at very small nozzle orifices which were not suitable for the locomotive. As a locomotive design becomes more Superpower, (4960+) it seems to becomes less responsive to Lempor affects and I agree with Mr. Koopman's comments more. One will also notice many firepan arrangements on Superpower locomotives use less admission air than the firegrate did. This allows firebox vacuum to be developed as well as higher velocities in the firepan tubes for better mixing. Yet, the amount of air that one would calculate such a large boiler requires is unsupportable by the small steam engines. So, UP stuck with a small amount of tubes and high vacuum. What you see in the early 3985 oil conversion videos is a lot of smoke, and very poor combustion as evidenced by the different darknesses of smoke coming out the stacks. Around 2000-2003, Matt Austin added quite a bit more tubes in the firepan to 3985 and you see less smoke, but quite a bit more blow back. That is about the limit of gas volume the front-end can move.

A 4000 is more Superpower than a 3900. To me, what that means is that converting a 4000 to oil firing is going to require thorough research of the past, and innovation and/or compromise on performance. Innovation will require invocation of the Scientific Method, which I believe would start with instrumenting a restored, coal-fired 4000 Class to gather data. It may well be worth testing the UP oil conversion afterwards, and reworking the firepan/burner arrangement form there to arrive at a tolerable solution.

Matt Janssen
Vapor Locomotive Company

Thanks Matt - an excellent explanation based on both practical and theoretical perspectives. Having never has the chance to work on a large and modern, close to superpower locomotive much less a legitimate superpower locomotive, I've thought the situation you mention would play out in the ways you suggest, but of course never knew until you shared it.

Improvement means choosing the limiting factor to peak performance, sometimes......and tweaking the other things you can control to work best with it. On the small locomotives I've worked with, the limiting factor in a lot of cases is the steam flow through the cylinder and saddle castings, and once you accept that, you can do the best you can around it.

The only universal limiting factor i know of is funding.

I appreciate your sharing, much to think about - best wishes.

dave

Matt,

Thank you for your response. So, just to be clear, the 4005, when converted to oil, it was basically the same arrangement as a oil-burning challenger? I assume that was the root cause of the purported poor combustion and high fuel usage.

Is there any reason why the burner set up on the cab forward at CSRM couldn't be copied for the 4000 class conversion? If my memory serves me correctly they were only a square foot or two different in grate area, and I don't recall reading anywhere that the ACs were poor steamers...why reinvent the wheel?

4884 1-2 & 4664 3-5 were added to the Thomas Burner drawing, 613CA33059 on 11-22-46. This burner also applies to FEF 1-3 and CSA 1-2. Most of the oil burning equipment drawings for the 4884 start from around this date and share components of additional classes. On my UP drawing index "ALLDATA LIST OF SCANNED DRAWINGS, as of 09-30-02", some drawings for the 4884 firepan and firewall are in 613, 614, 616 CA prefixes for Oil Burning Equipment, some are in 452 CA "Firedoor & Arch." Some appear for 4884 1-2, some as special "4005".

The UPHS has sold a CD of the drawings in the past and I am sure have refined the index of massive project Jules and company took on to save and scan these drawings. I would recommend everyone with an academic interest (or more) in this subject get a copy and study it and then we can all have a common basis for discussion.

I think the root cause of poor combustion is more complicated/broader than the oil burning arrangement itself just as a carburetor and intake are not the only factors on combustion quality of a gas engine.

For everyone's reference, said CD of drawings for 4-8-84s are available here:

http://shop.uphs.org/unionp02.html (Note: Item is currently out-of-stock, though the site promises an updated and improved version "soon" to be available."

And other UP drawings of interest:

http://shop.uphs.org/unionp03.html

Cab Forward comparisons would be smart. The Big Boy today might not be placed in the serious Sherman Hill demands for power than to just move happy fans. I'll repeat what I read somewhere, once the engine is working hard and the coal is being flung into the firebox, the fire is so hot and consumed so fast the fire would start to lift off the grates and the coal fully burned before it landed. Or so I read...

I would not want problems. Some Coal fire tests sound proper as we're working in some uncharted territories here.

It would just seem natural to use the cab forward burner setup, designed for that size of grate, designed for serious steaming capacity, proven design in service, original setup still in existence (not just a drawing somewhere)...does it matter that it would be a "period correct" design? Probably not, but then again, not a space age contraption that would need many months of computer simulations.

I think the exiting sentences from Nigel's post sum up the conversation, but that's just my opinion.

Perhaps the group that devised the oil-firing scheme for the Darjeeling-Himalaya Railway 0-4-0ST's could offer some input:



;-)

It seems to me that with all of the gas and diesel engines around (locomotives, road equipment and MofW) on the UP, maybe in the thousands, that there would be a lot of used lube oil available. Can that used oil be processed economically to remove any contaminants, or is this too 'old school'?

Thanks, this is one solution I have been working towards as a means of developing a waste oil burner that is as close to a vaporizing burner's cleanliness and efficiency as possible. Just because it can never get all the way there doesn't mean it shouldn't be taken as far as practically possible. There are 3 steps involved in what I'm looking at: settlement/separation, centrifugal cleaning, and filtering. My idea is that all of this be done in the tender tank or from the tender tank for the particular railroad in question......but if the operator has a fuel storage facility so much the easier and better.

Once we learn how clean we can make the fuel, we can work on how clean and completely burning a reversably retrofit firebox system we can develop to make optimum use of it.

dave

Hugh,
wouldn't you agree with me that the one name coming to mind as to successful modern oil firing is Roger Waller from DLM?

Cheers,
Mike

Mike,

Certainly Roger and DLM have had success with several locomotives using fairly high tech equipment. Nigel Day (who has also posted to this thread) has also had very good success on both small locomotives and locomotives as large as #4960 at the Grand Canyon.