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Herb W
03-03-2002, 04:02 PM
I've always used lithium based multi purpose grease for most applications. Recently started using grease with moly disulfide added, for direct metal to metal apps. such as pin & bushings.
Noted that southbend recommends teflon based grease for cone pulley bushings and I've also come across recs for silicone based grease (think it was for caliper slides - brakes on my old chev pickup)
Can anyone tell me what the attributes of these other grease types are?
Also, where do the synthetic greases fit into the picture? Are they worth the extra cost?

Thanks,
Herb

Thrud
03-04-2002, 12:21 AM
Herb
Most greases are one of several types:

Lithium is most common type grease. When a synthetic base oil is used the low/high temperature range and bearing speed is superior to any mineral oil based product. Moly is added (rarely above 5%) to increase the Timkin load rating as it is an extreme pressure additive.

Glyol based is used in places like kiln lines or carts but is generaly not available and should be avoided because of toxicity.

Aluminum Soap based is (or was) used by Ford in 4x4 hubs. Highly water resistant. To regrease with any other grease requires thorough clean out of the old grease as it reacts with other greases and polymerizes.

Aerospace greases include Silcone greases that combine extreme temperature ranges at atmospheric pressure down to absolute vacummns. Lubricity is minimal and usually used with specific materials.

Food Grade greases. Only one synthetic available (Amsoil - don't know part #), and few mineral based.

Specific application greases - these include extreme load greases for pile driver mechanisms (I know of one that has annealed Iron or steel powder instead of moly) and other severe applications.

Most people on the planet will rarely need anything but a standard NLGI#2 Chassis & bearing grease. Synthetics have proven themselves as the superior base oil giving lower friction, better performance under adverse conditions, and less wear. Using too heavy a grease can cause overheating and distruction of bearings. Over greasing is one of major cause of failure on properly installed bearings as well as the lack of lubrication

If you go to buy any synthetic (lubricant) you should be aware that the API has loose standards as to what is a "synthetic" - so ask if the base stock is a full synthetic (manufactured chemical - not re-refined or a minersl/synthetic mixture). Also some "so-called synthetics" will use petroleum based additives to reduce cost. Caveat emptor.

Dave





[This message has been edited by Thrud (edited 03-04-2002).]

Herb W
03-04-2002, 08:17 AM
Dave

Thanks for all the info!

The multi purpose grease that I'm using now is called epic 102 & has a part synthetic base oil.(one of the mineral/synth. types that you alluded to).

The synthetic component gives it characteristics of both 1 and 2 NLGI classes - hence the 102 designation.
Cost, I pay approx $3/cartridge, so it's less than the full synthetics. Hard to know how much dif there would be in performance - full synth vs part.

The moly grease I use is basically the same stuff, I think, just with the moly disulfide added.

I've read more than once (somewhere) that the moly greases shouldn't be used in bearings (ball or roller etc) as it can "build up" on the bearing surfaces. OTOH I've also read that it's included in some wheel bearing greases.
What's your take on this?

Herb

Thrud
03-04-2002, 10:21 PM
Herb
I do not know what you are using this on, but if you want a really excellent synthetic grease try Amsoil's "Racing Grease". It is $14 a tube up here but for precision stuff you will be real happy with it. It can also handle higher loads than greases with moly. It isa nice white color - so things stay nice and clean. Great for ski-doos and desert use too.

The Moly is added so that when the base oils film strength is exceded (thus allowing metal to metal contact) the moly will continue to protect the bearings. You can use a #2 Moly grease in wheel bearings and chassis including kingpins and u-joints - but a lighter grease is normally specified for things like half-shaft constant velocity joints - use the proper viscosity grease in these!

A truck driver I know hauls logs for the Diashowa paper mill in Alberta. His trailer lights worked until the day he put Amsoils GHD moly grease on the fifth wheel - then they would not work! Turned out that the ground wire in the trailer harness had broken . This tells me the regular greas allowed metalto metal contact while the Amsoil grease did not - the reason for grease in the first place!

You can't have a grease that is two NLGI designations unless it is breaking down when it warms up...

Herb W
03-05-2002, 08:32 AM
Dave

I use the greases on a variety of farm, seed plant, and shop machinery & equipment.

Not really looking to solve any particular problems, just seeking more knowledge.

I'll try some of the Amsoil grease, but at that price I'll be a little picky about what I use it for!

Thanks again for all the info!

[This message has been edited by Herb W (edited 03-05-2002).]

[This message has been edited by Herb W (edited 03-05-2002).]

paul wehrmeister
03-05-2002, 06:30 PM
i was talkink to a guy who rebuilds machinery he showed me a can of grease it was for lubing the bearings on a surface grinder he told me it was some un godly price i couldnt believe it looked like white grease to me he also said only one company made it does any body know anything about this grease is it a synthetic paul w

Thrud
03-06-2002, 03:18 AM
Paul, Herb

I had a customer with a German made pile driver. The grease used in the hardend bushing and shaft that the "vibrator" runs on uses a grease that has metal powder in it to buffer the shaft from the bushing. The gear box produces something like 20,000 Kg force and can drive pilings down 600+ feet. This particular grease is $200 US per tube. They use around 15 tubes to drive a single 600' pile! I also seen a grease for a vacuumn pump system that was $150 a tube and came in a glad freezer bag because it was dripping out silicone oils (not a Dow/Corning grease!)

The Amsoil Racing grease is white, the regular is red, the HD with moly is brownish red, the water resistant is blue, food grade is clearish white. They run from around $4/tube (general purpose)to $14/tube (Racing Grease) (Canadian retail). They are all Lithium greases and have 100% Synthetic base oils (some type of polyalphaoelifin made from renewable resources I was told). The food grade one I am not sure of its base compound.

[This message has been edited by Thrud (edited 03-06-2002).]

Herb W
03-08-2002, 03:46 PM
A few years ago, a salesman stopped in - wanted to sell me some grease. He took out two small spoons, each with a small hole in the bottom - filled one with the product he was selling, the other with my regular grease. He then applied heat (flame) to the spoon that held my grease - soon the base oil started to drip out, then the grease started to burn. Next, he applied the flame to the spoon with his product in it - nothing, no oil dripping, no fire.

He says "see how much better mine is". I'm thinking, this could be a very good high temp grease - or it could be some heat resistant goo that's utterly useless as a lubricant. Asked him for some technical info on his product - he had none, nada.

Price of course was outrageous, something like 10x the $ of my regular stuff.

He was persistent, but I was anxious to get back to work, so I told him - leave me your card, if I ever feel the need to operate with my machinery on fire I'll be sure to get some of that grease from you!

Hope he didn't waste too much of his time trying to sell that stuff, whatever it was!

[This message has been edited by Herb W (edited 03-08-2002).]

Thrud
03-08-2002, 08:36 PM
Herb
Have ever seen one of those machines the snake oil salesmen use - they call it a "Timkin Bearing Machine". They have a motor and a torque wrench to show how much pressure is applied to a roller from a timkin bearing held against a rotating sleeve. They put your favorite oil in and stall it out on the "One Armed Bandit" (the technical name for their so called Timken Bearing Machine). Then they put an additive in - low and behold, they can't stall it now! What they dont tell you is this:

Coca Cola would keep it running longer, but would you put coke into your motor - NO! Clorinated Kerosene will do the same thing - don't use it! Sulphurized oil will as well - forget about it! It is because they are extreme pressure additives - that is what they do!

An actual Timken Bearing Machine did exist, it was used to measure the film strength of greases and Gear Lubes. It used a Timken bearing cup rotated against a steel block. A computer added weight until galling occurs and the film strength was then known - sort of. ANSI dropped it as a valid test because you could run 100 tests and get 100 different results and was therefore invalid as a legitimate laboratory procedure. It looked similar to a bridgeport, big ugly - useless.
It was replaced by the four ball wear test which rotates a ball bearing against 3 others inside a cup filled with the lubricant. The apparatis is elevated to test temperature and a fixed pressure is applied for a legnth of time. The result is a scar on the balls whose diamter to measured to determine the lubricants RELATIVE FILM STRENGTH (not absolute - only an indicator). The larger the scar diameter the more significant the wear is. It is still the most effective test for film strength available but is not ANSI certified as of yet.

Thought you might find that interesting. By the way, the ONLY additive that should ever be added to any equipment is one the Manufacturer approves (limited slip additive for differentials is the ONLY one I know of...) for use in their equipment. They can deny warranty on damage from additives - easy to prove with oil analysis.

Herb W
03-09-2002, 12:58 PM
Dave
I haven't seen the timkin machine, but I've heard of it, and other gadgets that the sales guys have used to promote their products. If you think it through, they usually don't really prove anything - at least not anything relevant.

Agree with you on additives. 25 yrs - numerous thousands of hours on a bunch of different diesel engines - never put anything but oil in the crankcases - 0 failures so far - the oil must be working!

Something I've wondered about; how does one compare the quality of the different brands of oil? They all meet the same API specs and of course each dealer claims that his is second to none. Is there any independent testing done?

Thanks again for all the info!

[This message has been edited by Herb W (edited 03-09-2002).]

FLPR@juno.com
03-09-2002, 03:53 PM
A long time ago I worked in service stations.(1950's) Several times salemen came around with a ball bearing device to demonstrate how much their additive would cut down the friction. It really worked! Later, I found out about some research done on friction during the 1930's. The friction in a beearing that was oil lubricated could be cut nearly 90% with a simple additive. The catch? The additive was oleic acid. Do you want acid in your car or machinery bearings?

Thrud
03-10-2002, 01:23 AM
Herb
I would only recommend two synthetics Amsoil (100%) or Mobil (not 100% synthetic base stocks/addititves). In that order. If I could not buy the Amsoil I would buy Mobil - no others. I have seen engines (diesel) that have had over 1/2 million miles that were within spec for a new engine (wear was minimal). I have seen gas compressor engines running on regular lubes that where so coked up that a partial overhaul is required after 1200 hrs., but 25,000 hrs after a 14TBN synthetic was used no signs of carbon could be found in the oil analysis or in the boroscope inspection.

Now the bad part. Because sysnthetics offer such high film strengths they tend to leak in equipment with marginal sealing to begin with. A crack that is filled with carbon using regular oils will be cleaned out quickly by the synthetic because of its high detergency. The dispersants in the lubricant then clump these carbon particles together until it is large enough for the filtration system to remove it. The bad part is now you have a clean crack where carbon previously filled in. Because of their high film strength the capillary action is greater with synthetics - hence it starts to leak - a lot. Not the Lubricants fault, it was the leeching of the plastisizers by the petroleum oil that caused the gasket or seal to get hard and crack in the first place. Synthetics tend to keep seals and gaskets softer and more supple.

That is why they tell you to change you oil every 3000 miles or less (I would say 600 mi tops myself). For a unit with hour meter multiply the time by sixty to get approximate milage - idling decreases life of the lubricant and wastes fuel. Long drain intervals are becoming mroe common on fleets and HD trucks.

Highway tractors can get over 1 million miles without dumping the oil using proper filtration and sceduled analysis of the Synthetic lubricant (with minor top offs for filter changes and make up for turbo losses, etc). Synthetics are never recommended on any equipment that is poorly maintained or mechanically unsound because of the possibility of major leaks.

API - American Petroleum Instutute. Funded, run, and policy directed by guess who - the petroleum companies. The standards are very loose to be kind, their standards are substandard compared to European and Japanese basic requirements. API also charges to use their Symbols and name on products. To get the API "starburst" you have to pay so much per qt sold and submit your formula to them - they say for quality control.

Every Lubricant company does research. They all know how bad or good the other guys stuff is. Nobody will tell you how bad oil "x" is because of lawyers - it is considered "bad manners" in the industry. Be aware too that large companies like Mobil supply base components (chemicals) even to their competition! (this does not mean that Mobil makes that company's product - they simply supply "pieces" for it)

Usual disclaimer - no financial interest in any of the forementioned companies, organizations, or products.


[This message has been edited by Thrud (edited 03-10-2002).]

Herb W
03-10-2002, 09:27 AM
FLPR
When I read your post, oleic acid rang a bell. There's a component in flaxseed called linoleic acid - wonder if that's where it came from?

For lube products (and most anything else I 'spose) now as then it's buyer beware!

Dave
Once again, thanks for that info!

[This message has been edited by Herb W (edited 03-10-2002).]