Caterpillar's oily past - PeachParts Mercedes-Benz Forum

seo · #1 11-27-2006, 03:05 PM

I just saw this in a website that belongs to Caterpillar, and thought that it might be of interest to diesel lube oil commentators.

"Just as diesel power was beginning to take hold, the world caved in on the young industry. Engines that had gone 3,000 hours without ring sticking or liner scuffing were suddenly dying at 300 hours. As the piston rings got stuck in their grooves, the engine lost compression. As the engine lost compression, it lost power. Eventually, there would not be enough compression for ignition and the engine would not run at all.

"The engine manufacturers blamed the oil companies and the oil companies blamed the engine manufacturers. It took several years before everyone realized that a new refining process introduced in the early 1930's had removed naturally occurring detergents from the crude oil. With the detergents gone, there was nothing to inhibit the formation of combustion by-products in the ring grooves, which eventually led to the ring becoming stuck in the groove and not sealing. At this point, a serviceman would have to pull each piston and scrape off the accumulated sludge after applying a boiling bucket of chemicals to the piston. Caterpillar knew there had to be a better way. In discussions with the Shell Oil Company, a chemical was identified that did not require boiling to remove the sludge. It was a chemical detergent. One enterprising serviceman started putting the chemical in the engine crankcase just prior to each oil change. As he drained the oil, he also drained the dissolved sludge. This process quickly evolved into adding small amounts of the detergent to the oil to replace the natural detergents that had been present in the crankcase oil just a few years before. From that point, the Shell Oil Company started adding the detergent during production back at the refinery.

"In an effort to cut through the brand loyalty of consumers, and at the same time insuring that Caterpillar engines received the proper type of lubrication, Caterpillar started issuing certificates to oil companies whose detergent oil was approved by Engineering. Since other oil companies did not want to be left out, Caterpillar was put into a position of having to create standards for diesel engine lubricating oil. After investigation, Engineering was convinced that it was impossible (in 1935) to evaluate a lubricating oil on the basis of chemical and bench tests. They only had confidence in actually testing the oil in an engine. To facilitate this, the one-cylinder engines that Caterpillar used for development work were made available to the petroleum industry to test oil performance. One-cylinder oil test engines are still manufactured today."

vstech · #2 11-27-2006, 03:57 PM

ya think that is where the "C" rating on diesel specific oil came from? CI C4 etc...
John
oh, and hey, post a link to that page for us...

#3 11-27-2006, 11:29 PM

S= Service
C= Commercial

seo · #4 11-28-2006, 07:06 AM

I'm next to absolutely certain that "S" stands for "spark" ignition, and "C" stands for "compression" ignition, otherwise known as diesel. The place where "Caterpillar" graded oil became significant in my life was in the '70's, when standards for diesel fuel were relaxed to allow higher sulpher content. At that time some lube oil was labelled as "Cat Series 3" oil, which signified that it had higher capacity to disperse (or suspend, I don't know which) sulpher.
Caterpillar operator's manuals usually include quite long and weighty pronouncements on oil. They take it pretty serioiusly, and I was interested in this little article above because it shows that they've been taking it seriously for a long time.
seo

#5 11-29-2006, 01:50 AM

Quote:

Originally Posted by seo

I'm next to absolutely certain that "S" stands for "spark" ignition, and "C" stands for "compression" ignition, otherwise known as diesel.

From The API website: http://new.api.org/aboutoilgas/motoroil/api-quality-marks.cfm
"These letters officially stand for "Service" and "Commercial.""

vstech · #6 11-29-2006, 12:31 PM

Yup, apparently the c rated oils are for two stroke gas or diesel, and four stroke Diesel...
http://new.api.org/certifications/engineoil/categories/upload/EngineOilGuide2006.pdf
John

vstech · #7 11-29-2006, 12:34 PM

Quote:

Originally Posted by vstech

oh, and hey, post a link to that page for us...

I did find this page...
http://ohe.cat.com/cda/layout?m=85361&x=7

seo · #8 11-29-2006, 03:10 PM

Here's the actual passage from the API website:
"The letter "S" followed by another letter (for example, SM) refers to oil suitable for gasoline engines. The letter "C" followed by another letter and/or number (for example, CI-4) refers to oil suitable for diesel engines. These letters officially stand for "Service" and "Commercial."

So how do they get one sentence to follow from the other? What the Hell does "service" mean when related to oil? Why do they tell us that "The letter "C"... refers to oil suitable for diesel engines." and then tell us that it means "commercial?" I have a gas engine powered bulldozer, a gas engine Case 411 tractor, you get the picture. These are commercial gasoline engines. But wait a minute-what does "commercial" mean? That the engine is used in commerce? So the florist delivery van is engaged in commerce, but the diesel engine in a tank is not, because warfare is not commerce? Seems like the word they were searching for is "industsrial," because that's how the engine manufacturers break down the horsepower curves of their engines, between industrial service and others.
Well, who cares? Just remember that a "service" engine has spark plugs to ignite gasoline, and a "Commercial" engine relies on compression to ignite diesel fuel, and you'll be just fine.
seo