Jason C. has a number of times mentioned "light at the end of the tunnel" concerning grease for locomotive use. Jason I always like to here your perspectives, how bout it?

Cheers, John.

"Old" chemist speaking here. Back in the '60's when I took my early chemistry classes, greases were defined as mixtures of oils with soaps. Who knows what has happened since then in regard to greases, I don't know - I got involved with polysaccharide chemistry.

But, in regard to the comment about glycerine being mixed in with the grease, that would have to be true, unless it was removed. The Texaco article says the grease was made by cold saponification of fats along with mineral oils added. All animal and vegetable fats and oils are "triglycerides," esters of fatty acids with glycerine. Saponification, soap making, consists of reacting fats and/or oils with caustic soda (sodium hydroxide, lye) [or potash to make a potassium soap]. This breaks the ester bond, yielding the sodium (or potassium) salt of the fatty acids (soap) and glycerine. So, unless it was removed somewhere else in the process, the Texaco product would contain glycerine.

There would be lots of "voo-doo" involved here. Properties of the final product would vary depending on the starting fat - animal or vegetable, beef, pork, corn, palm, castor, etc. Properties such as viscosity, resistance to heat, etc. would vary depending on what was used. Then add in the properties of the lubricant oil. Especially back in the day, lots of art or voo-doo would be involved. People with lots of experience in that area were probably much more valuable than "scientists."

The company I worked for found that out the hard way. We started with a natural feed stock. The guy in charge had worked there for something like 40 years. He retired, and instead of replacing him wit the guy who had been there for 25 years, they brought in a new PhD chem engineer. Took him months to be able to get a decent product made, and that was only after they had to bring the retired guy back as a consultant.

I am going to recommend a book entitled “Which Oil?” by Richard Michel ISBN number 978-1-845843-65-6. While geared toward automobiles it has some info relevant to trains in it. On the subject of my swamp cooler, the squirrel cage runs plain bearings without an oil filter which is the reason it calls for non detergent oil. Plain bearings can easily be found on many steam locomotives in many locations. According to the movie Running Steam Locomotives Volume II Passenger Locomotive Road Operation even the UP 844 does not have roller bearings on the rods.

Robby Peartree

Don't think anybody said it did, Robby. The thread is about journal bearings and block grease, not rod bearings.

Rod bearings were mentioned by Mr. Austin when the thread began, but I do not know of any instances of rod bearings being smoked due to poor quality grease. Anybody else care to chime in that may have more information?

I was under the impression, from this and other threads, that the grease available today was ok for rod bearings, but not for the main bearings.

So, to be clear, the original Texaco M grease is the 'mythical' grease that works in locomotive main journal service? Were there any others made that also worked?

Here we go.... grease 101.

The formulation Matt posted the info on is infact out dated for reasons others mentioned in regards to locomotive size, bearing loadings an resulting temps.

By the late 30's texaco had perfected the grease we know and love under the name of "Hytex 8" which was their journal bearing compound (hytex 6 was the rod compound).

This formulation of grease no longer utilized steam cylinder oil, rather they utilized the same proprietary blend of raw base stocks as was/is utilized to this day in Marfak/Multifak "soft grease". Markfak, incidentally, was nothing more than a soft hard grease. It had a soap content of only 30% versus journal compound which was running about 55%.
There were no exotic materials used in the production of Hytex 8, it consists of 55% sodium tallowate (or palmate depending on era of manufacture) soap with the balance being a blend of two base stock oils with a nominal viscosity of ISO 600. The consistency or hardness (penetration rating) of the grease was achieved by oxidizing the grease via compressed air mixing in a covered kettle while heated to a temp of about 500 degrees (IIRC) for a period of 6-8 hours. Additionally, the cooking of the grease in this manner is also responsible for the ever important high "drop point" (the temperature at which the oil falls out of suspension with the soap base) associated with Hytex 8.
Greases of today have a formulation of Sodium Stearate including additional thickeners to achieve desired hardness AND utilize oil with an ISO rating of 70-100. In addition to the oil being notably thinner than that of hytex, the additional thickeners leave the grease vulnerable to "glazing over" if things heat up a bit. Sadly, since phillips 66 ceased selling sodium tallowate hardgrease with a proper weight oil about 5 years ago this is the best that has been available.
The penetration rating for the hytex grease was about 60 with 300 grams extra weight applied to the cone. Greases of today have a penetration rating of 35 with no extra weight added resulting in a grease that more closely resembles rod compound in regards to hardness.
I have over the last 5 months done exhaustive research in this matter obtaining formulations, speaking to grease scientists (as they are called) from several different corporations located on a few different continents. As I am writing this on the fly I may have left out some obvious details, if anyone has ANY questions, feel free to ask.

Now, FOR THE GOOD NEWS! After having identified some two dozen manufacturers of hard grease around the globe one has been identified as making a spot on match for both Hytex 8 and Hytex 6. This international supplier just last week sent me a 20lb sample of the grease which consists of a blend of Sodium Tallowate/ Sodium Palmate soaps, a base stock oil with an ISO 560 rating and a penetration rating of 35-37 with 150 grams extra weight on the cone. Nothing additional, no additives, the grease is made in the same manner as Hytex 8.

This week a sample of this new grease will be tested side by side with a sample of Hytex 8. By the numbers, by the supplied formulation versus that of Hytex, I fully expect the results will be most favorable.

Again, if anyone has any questions..... Fell free to ask!

Cheers, Jason

Jason,

Besides the different uses (rod v. journal) what were the differences in Hytex 6 and Hytex 8?

Many thanks, and very informative.

Easy enough, the 6 contained only about 42-45% soap and the balance oil. So, simply put.... It contained more oil than soap.

Cheers, Jason

Jason,

Thanks. Is the difference between Hytex 6 and modern Markfak close enough that it can be used in rod bearings without much of a problem? I see the soap content of Hytex 6 is higher than modern Markfak, but was wondering if this difference would be significant.

Or are you working on some new-made Hytex 6 as an encore?

David

It can be derived that the Marfak 3 would not be suitable at the least for higher speed applications. Marfak 3 was utilized in valve gear, spring rigging, etc. all of which see only oscillating motion where rods see rotational motion.
As the temp increases the grease expands, flows out of the reservoir and into the bearing. Soft greases have a lower percentage of expansion per degree of temperature increase for a given volume than do hard greases. In addition, I have seen locomotives that use one type of soft grease or another on rods and they all have grease built up around the collar which has a slight bronze hue. The soft grease traps to much particulate matter and essentially becomes a honing compound.
I can't quote the specific mechanics as to why hard grease does not do this..... But, it doesn't.

The company I am dealing with does also offer a spot on match for Hytex 6 but at this time I don't see the need to import such a product as Hytex 8 (while the supplies lasted) worked perfectly well as did the commonly available post texaco hard grease until recently. Also, I have a partial list detailing what railroads bought what in terms of hard grease in the latter years of steam and out of a dozen or so listed only 1 was purchasing rod compound.

So yes, for an "encore" I could also facilitate the supply of rod compound but why?

Cheers, Jason

quote
Rod bearings were mentioned by Mr. Austin when the thread began, but I do not know of any instances of rod bearings being smoked due to poor quality grease. Anybody else care to chime in that may have more information?

I was under the impression, from this and other threads, that the grease available today was ok for rod bearings, but not for the main bearings.[/quote]

I stand corrected.

However, let's get the terminology straight. "Main bearings" refers to the rod bearings on the main driver crankpins. "Rod bearings" are all the other crankpins. "Journal bearings" are on the driver axles (also engine and trailer truck, tender, etc) and were (I think) the thrust of the thread about grease, since there has been so much trouble with said bearings running hot on a number of plain-bearing locomotives when using modern grease as compared to the old greases.

Rod bearing grease available today does the job well, assuming that the pins and rod bushings (bearings) are machined to the correct sizes,shapes, and tolerances; that everything is in tram, and in quarter.

I am personally aware of one locomotive that runs a few times a year that came under new management. The new head man decided to replace the rod brasses with new ones, machined to gnat's eyelash tolerances, because he didn't like the noises they made. To no one's surprise but his, everything suddenly ran hot. Smoking hot. This lead to a blame game, starting with blaming the grease (which had worked just fine for decades), blaming the shops that did the machine work, blaming the material the brasses were made from.

The cure was simple: They quietly opened up the tolerances and, like magic, the overheating went away, suddenly the grease was just fine again. There are still mutterings about the shops and the bronze foundry, but nobody buys those tales now.
The rod bearings are noisy again, too, and a search is still on to find a way to make them silent.

Sometimes, fixing things that aren't broken actually breaks them. Then the search for scapegoats begins, and occasionally that ends up with blame being cast on things that have nothing to do with the issue.

How many times have I heard the saying "I'd rather hear them than smell them".
A lot of people confuse steam locomotives as highly precision machines. They are, but a looser tolerance high precision machine. Heat, tram, fit and many other things have to be considered.
We never had any problems with the "substitute" HY TEX 8 using it to dope the rod pins. It just didn't do the job in driving box grease cellars. I've been hearing the story for 25 years now that somebody has formulated an exact duplicate to Hy Tex 8.
From what I've heard, it's like the old style of making meth, cooking it can be disastrous and dangerous and no reputable company wants to fool with it.
I've often wondered how it would have worked out if we had converted to oil on the driving axles on 1522.
There are more things to be considered besides the grease. The screens, the fit of the screens and pressing the cakes until no air pockets remain. It's gotten to be a forgotten art for mainline running.
Book 'larnin is fine, but following the examples of our predecessors who had to learn the hard way means more to me. Reinventing the wheel and fixing things that aren't broken will bite you in the butt sometimes. There are far enough things to fix on steam engines, so if it's right, leave it alone.

Back when the CNR was operating 6060 in excursion service there was a sign on the wall of the Spadina Roundhouse in Toronto stating which lubricants were to be used on the locomotive.

It specifies a product called Obra 30 Grease for All Rods, Wrist Pins & Driving Boxes and Driving Box Cellars.

http://www.trainweb.org/j.dimech/6167/6060-lub.html

Correct you are! Sadly, Obra 30 (though it is still listed in places online) went out of production just a year or two ago. The oil used in this product was heavier than the modern day stuff but still not quite up to the Texaco spec. Also, while the drop point is higher than some others it too falls short of Hytex 8.

http://www.imperialoil.ca/Canada-Englis ... EsObra.pdf

Cheers, Jason