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View Full Version : How does a Machine Designer pick an oil?



Mcgyver
05-23-2009, 09:18 PM
So exact a science is this, machine designers selecting what oils should be used? I suppose at some intellectual level it comes down to engineering, psi and all that, but there seems such variance. I mean is the design, pounds per square inch on bearing ways, size and fit of the gears, type of bearing used, etc, that much different than other mills in this size? Yet the oils vary quite a bit from machine to machine -32, 50, 68 and mine 90w.

My Elliot calls for Vitrea 37 which near as I can figure is the same as a 100 ISO or about 90w gear or hydraulic oil . It's prescribes throughout - gearbox, ways etc. Perhaps in a gear box there's engineering to be done, but the ways? how much different can they be between other machines in the same class?

its a @#$@# to find, so i think I'm going with 68, but it just got thinking as to how much rhyme or reason there is to the specified oil??

John S, what are you using in the Victoria?

DR
05-23-2009, 10:02 PM
I took a class in lubrication theory years ago.

The one thing I still remember is the instructor saying to use the thinnest oil that the seals or configuration will contain.

Forrest Addy
05-23-2009, 10:06 PM
It aint rocket science. Oil is oil and even the wrong oil is better than no oil. I stock 4 oils and 3 greases and these fulfil 99% of my lubricating requirements. Get hold of a good cross ref fror lubricants modern and historical. Learn what lubes are generally used f[r what purpose. After you build a little discration about lubricants and lubrication you can wing it.

Oh, your question: how does an engineer pick an oil? His outfit usually has a 4 lube policy too and a cross index. As for brand: safe assumption - he specs the brand whose rep last bought him lunch.

saltmine
05-23-2009, 10:28 PM
I learned a valuable lesson about oil last week.

I usually oil the ways and leadscrews after cleaning up my machines. This time I noticed I was out of 30 wt oil that I normally use. But I had some Amzoil 5W30 synthetic oil from a recent oil change in my car. So, I poured some of the synthetic into my oil can and lubed everything up real good.

Well, since I got busy with something else for about a week, I forgot about the synthetic.
When I went to machine a part on my lathe, I noticed the handles were silky smooth, but the cut was terrible. I resharpened the M2AL tool bit I was using and tried again. Still the finish was bad...and the handwheels were creeping.
WTF?? I tried carbide, still lousy. But, I noticed the crossfeed handle was actually creeping while making a cut.
The synthetic oil! I got out a can of "Brake cleaner" and sloshed down all of the ways, lead screws, and feed gears. After the cleaner dried, I re-oiled everything with plain 'ol 30 wt oil. The next pass was almost mirror finish...
Could it actually be the synthetic oil?

airsmith282
05-24-2009, 12:10 AM
i use 30 w non detergent in my gear box and my ways and every where else on the thing and yes i can get a mirror finsih as well , i been using the 30 w on my hole lathe sence the day i bought it , and i wont change, way oil is BS ,its another exuse to spend money...even busy bee told me the 30 w was the better choice even though my book says 10w ,, the 30 w it runs smoother and quieter and i get great results...i have also started to do more dry turning as well and finding iam also getting better results as well on alot of the stuff iam doing,, where before well it was a challange,,

fake oil is just that its fake and no good fr nothing and its very bad for your car as well..

people that know what the hell is dip stick is use real oil and we have less engine problems then thoes using fake oil, its fake its gota be good is the way they think sad to say on the same note thoes that know what the dip stick is also us fake oil and they have more problems over time as well then thoies that know the dip stick and use real oil..

some guy ask me to put fake oil in his car or any engin he has itell home go else where and get riped off iam and honest guy,,

then they are like what are you saying,, well go put vegtable oil in it, it will last about as long well maybe not but you get the idea guys. ok

not every thing you read is true or LAW ,

my son use to belive everything he read and thougt of it as its the only way it is and thats it well he learnd different now,,

my x wife calls me up, iam the computer expert here, also the most trusted , any how, she has this problem with her printer , tell me she called the place and they did this and did and still its half dead and wont print but it scanns so its half alive i tell her call back ask to talk to someone that has a brain in there head , the daughter board is shot 5 other people say no its the software, well not if you did a freash realod and all the drivers are in and you ahve also tested other devices onthe USB ports and they check out , ok morons ok thats what they are over paid morons and they want to give her a 300 dollar bill to have it looked at buy someone else they gave up on her , and blame the software, dummies got no brain in there head and call them selfs computer technitions that ar IT certified and trained well.. any one with half a brain cell would know its a 3 in one printer scanner fax and it runs indpendent boards on one main board in this case and it can stil runsome features if the others are down aka blown , the tech there dont even know the product they sold her ..

get the idea here,, not trying to hi jack the thread but just show and example
which also further shows not to belive everything you read its not always LAW whats in the books or what people say..

use quaker state motor oil its the best , well same crap as tech 2000 from walmart at 2 times the price ..
auctually its worse and still more expensive but thats another story,,

use the 30 w on your ways, its not a problem and its not a hi precision million dollar machine that must have it ,,

anyhow on that note good nite and happy machining

jacampb2
05-24-2009, 07:55 AM
:eek: Wow, just... Wow.

I use pretty much just Iso 32 and 68 in my machines. I buy it in big 5 gallon buckets from Napa.

I have opened machines and found all sorts of crap in them. There is no way I would put automotive gear oil in anything critical. Its specifications are not highly controlled, and it smells like a rotting swamp... Iso 100 oil is less than half the viscosity of 90W gear oil (middle of the road spec, 90W can be anywhere from ~125cST to ~300cST at 40C. Iso 100 has a spec of ~90-~110cST at 40.

If I am not mistaken, the "Iso" oils are graded according to their viscosity. I use Iso 32 in oil baths, and Iso 68 on sliding surfaces.

If you manage to decipher the recommended oils on any old machine, you will typically find that they match to any of the commonly available ISO xxx hydraulic oils.

Later,
Jason

Mcgyver
05-24-2009, 09:40 AM
thanks for the replies, as to how designers select oils, i guess I'm still in dark but Forrest I think nailed how they select brand. I guess its less finicky than say how a violin maker selects his wood (which can come down to which side of the tree the sun was on).

As to what I need, Jaso, your post made me realize how ignorant i am of viscosity. I'd erroneously assumed the the "number" was viscosity not realized motor and gear oil were completely different series....ie the "80w" on the gear oil scale is NOT thicker than 30 on the motor oil scale.

http://i20.photobucket.com/albums/b201/michael0100/oilviscosity.jpg

The Shell Vitrea 37 i can't find, but i've found lots of other Vitrea oils.....http://www.shell.com/static/au-en/downloads/lubricants/product_data_guide/technical_properties.pdf
the Vitrea number is always the ISO number. So if what i read, that Vitrea 37=iso 100 is wrong and its in fact its ISO 37 I need....wow that's a much lighter oil than I'd been thinking...10-20w on the motor oil scale. does that seem right?

are hydraulic oils graded on the same scale as motor oils, ie would an 10 or 20w hydraulic oil equate to an ISO 37?

thanks

jacampb2
05-24-2009, 11:27 AM
I have never personally seen a hydraulic oil, sold as such, that was graded in the "wt" measurement. The stuff I buy is mobile brand ISO 68 and ISO 32 hydraulic fluid. Even the tractor supply who sells "universal hydraulic and transmission oil" doesn't grade it in the "wt" scale.

I think the important part is to get as close to the recommended viscosity as possible, and to use an oil w/o detergents, friction modifiers, and other stuff intended to be used in IC engines.

You can blend the oils to arrive at the needed viscosity, it would probably be much easier to go to the local farm store and buy a gallon of ISO 68 and 32 and blend to get your 37 cST variety then it would be to hunt for someone who is still producing it.

Later,
Jason

jacampb2
05-24-2009, 11:32 AM
There is a Shell Tellus Oil T 37, listed on page 7 of your linked document, and it is indeed 37 cSt oil...

Good Luck,
Jason

Cheeseking
05-24-2009, 12:50 PM
Now I'm curious. What exactly is "fake" oil??

Also, what is a "hole" lathe??

saltmine
05-24-2009, 01:05 PM
Well, I know not to use synthetic oil on the moving parts of my machine tools, but....for automotive use, I beg to differ.

Sitting in my driveway is an eight year old car, with over 100K on it. After a break-in on conventional motor oil, I started using Amzoil 5w30 pure synthetic. The car picked up 2mpg when I switched over, and is tight and free of leaks. It uses no oil between changes (I usually change the oil @ 16,000 mile intervals) When it's ready to be changed, the oil is as clear and clean as it was when I first put it in. I'm a retired mechanic with over 40 years of experience, so I should know where a dipstick is. I've seen and had to repair sludged up engines (from paraffin based oil, AKA Penzoil)

Next time you board a jetliner to take a trip, look out at the wing. See that jet engine hanging out there? Probably cost $1.2 million. If you had to pay for it, you'd want the best oil, right? ALL jet engines use synthetic oil for lubrication, always have, always will. "Turbine oil" is all pure synthetic...And, if you knew anything about your "fake" oils, you'd know the original founder of Amzoil created the original formula by blending conventional and turbine oil together, eventually settling on full synthetic.
If you don't believe me...go to the Amzoil web site and look at the International diesel engine they took out of a school bus that ran for 275,000miles without changing the oil (the oil was Amzoil). NO measurable wear.

Paul Alciatore
05-24-2009, 01:19 PM
It aint rocket science. Oil is oil and even the wrong oil is better than no oil. I stock 4 oils and 3 greases and these fulfil 99% of my lubricating requirements. Get hold of a good cross ref fror lubricants modern and historical. Learn what lubes are generally used f[r what purpose. After you build a little discration about lubricants and lubrication you can wing it.

Oh, your question: how does an engineer pick an oil? His outfit usually has a 4 lube policy too and a cross index. As for brand: safe assumption - he specs the brand whose rep last bought him lunch.


Great answer. I suspect that the design engineers rely more on experience than anything else. If you have been designing lathes for 35 years, you pick up some knowledge about what works and what doesn't. Observation of the problems, complaints from customers, problems solved, etc. Forrest alludes to this.

And don't discount the free lunch thing. I have learned a lot at such things and a brand preferance can last a long time even in the presence of the the sure knowledge that other brands are equally good. I think you tend to have more confidence in a company that takes the time and effort to contact you personally.

Cal Haines
05-24-2009, 06:50 PM
Motor oil should not be used in a machine tool. It's designed to hold debris and water in suspension until the oil filter can remove the debris and the heat of the engine can drive off the moisture. In a machine tool you want the debris to precipitate out and you don't want it to hold water. You don't want the fine grit to stay in the oil and keep getting on the gears, etc..

Try this: Get two glass jars. Put motor oil in one and machine tool gear oil in the other. Put very fine grit and water into each. Shake the jars. Let them sit for a week.

Cal

ligito
05-24-2009, 08:09 PM
Now I'm curious. What exactly is "fake" oil??

Also, what is a "hole" lathe??

Synthetic.
One that is used for making a hole, using the whole machine.:rolleyes:

Give the guy a break, he may,or may not be typing in a second language, give him the benefit of the doubt.

bollie7
05-24-2009, 11:24 PM
:eek:
I There is no way I would put automotive gear oil in anything critical. Its specifications are not highly controlled, and it smells like a rotting swamp...
Jason
Thats interesting, so what do you run in your car gearbox (if its a manual trans)?
Think about it. An automotive gearbox is pretty critical, has to handle a lot more power than your average HSM machine (Don't know about the torque) Has to handle extremes of temp, vibration, uneven loading and general abuse from a variety of drivers, yet generally, most gearboxes seem to survive for a lot of distance using automotive gear oil.

bollie7

rotate
05-24-2009, 11:54 PM
... When it's ready to be changed, the oil is as clear and clean as it was when I first put it in. I'm a retired mechanic with over 40 years of experience, so I should know where a dipstick is. I've seen and had to repair sludged up engines (from paraffin based oil, AKA Penzoil)


I agree that synthetic oil for automobile is far superior to the mineral based ones, especially for turbo charged engines, however if the drained oil is as clear and clean as when it was new, then I don't think the oil is doing its job.

chief
05-25-2009, 06:08 AM
Not to highjack anything but on the subject of machine lubrication I recommend Castrol or Girling red rubber grease for all seals and O rings.
It keeps the rubber soft and supple as a young babe's butt.
It also keep CV joint boots from cracking, just light coat applied with your fingers.

airsmith282
05-25-2009, 08:05 AM
Now I'm curious. What exactly is "fake" oil??

Also, what is a "hole" lathe??


olk spelling error on my part should read Whole lathe ,, ok fake oil is that synthetic crap its not real oil its FAKE oil and the crap anit no good for nothing..

you want to live on tofo its fake food to just like the oil is ...

i prefer real food bacon is bacon hamburgers are hambugers ,,

oil is oil and synthetic oil as its called is fake oil...

airsmith282
05-25-2009, 08:15 AM
Well, I know not to use synthetic oil on the moving parts of my machine tools, but....for automotive use, I beg to differ.

Sitting in my driveway is an eight year old car, with over 100K on it. After a break-in on conventional motor oil, I started using Amzoil 5w30 pure synthetic. The car picked up 2mpg when I switched over, and is tight and free of leaks. It uses no oil between changes (I usually change the oil @ 16,000 mile intervals) When it's ready to be changed, the oil is as clear and clean as it was when I first put it in. I'm a retired mechanic with over 40 years of experience, so I should know where a dipstick is. I've seen and had to repair sludged up engines (from paraffin based oil, AKA Penzoil)

Next time you board a jetliner to take a trip, look out at the wing. See that jet engine hanging out there? Probably cost $1.2 million. If you had to pay for it, you'd want the best oil, right? ALL jet engines use synthetic oil for lubrication, always have, always will. "Turbine oil" is all pure synthetic...And, if you knew anything about your "fake" oils, you'd know the original founder of Amzoil created the original formula by blending conventional and turbine oil together, eventually settling on full synthetic.
If you don't believe me...go to the Amzoil web site and look at the International diesel engine they took out of a school bus that ran for 275,000miles without changing the oil (the oil was Amzoil). NO measurable wear.

ok then you say "When it's ready to be changed, the oil is as clear and clean as it was when I first put it in"

now fo thies thathave the digitial tattle tail on out dash like i do we know when to change hte oil what about thoes that dont have it, or better yet if its still just as clean and clear thats odd but ok,, well do you change it every 5000 or is it 10,000 miles cause i heard the stuff last 2 times longer but your saying when it time well to me if its still clearish its good ,, my car when it says 4% left i change the oil and its usually black at that point..

so why change it then if it has not changed in color at all etc..

if it aint broke dont fix it right.. so help me understand this please iam interesed in hearing about this one,

wendtmk
05-25-2009, 08:37 AM
Thats interesting, so what do you run in your car gearbox (if its a manual trans)?
Think about it. An automotive gearbox is pretty critical, has to handle a lot more power than your average HSM machine (Don't know about the torque) Has to handle extremes of temp, vibration, uneven loading and general abuse from a variety of drivers, yet generally, most gearboxes seem to survive for a lot of distance using automotive gear oil.

bollie7

Well, in my 1998 Chevy Camaro Z28 with the six speed manual transmission, GM calls for automatic transmission fluid. 220,000 miles, and still going strong.

Mark

A.K. Boomer
05-25-2009, 10:09 AM
Well, I know not to use synthetic oil on the moving parts of my machine tools, but....for automotive use, I beg to differ.

Sitting in my driveway is an eight year old car, with over 100K on it. After a break-in on conventional motor oil, I started using Amzoil 5w30 pure synthetic. The car picked up 2mpg when I switched over, and is tight and free of leaks. It uses no oil between changes (I usually change the oil @ 16,000 mile intervals) When it's ready to be changed, the oil is as clear and clean as it was when I first put it in. I'm a retired mechanic with over 40 years of experience, so I should know where a dipstick is. I've seen and had to repair sludged up engines (from paraffin based oil, AKA Penzoil)





I can attest to your claim about penzoil sludging up an engine --- Where you would really notice this is with heat, and no engine cooked their guts out more than the common air cooled volkswagon, add living in a mountain state and it even gets worse, I remember pulling the valve covers and having black waxy burnt crap drop all over the shop floor -- ask the customer if their using penz -- yup --- occasionally you get the quaker state reply - that's another one --------- this is old news so take it for what its worth - don't know if they've finally modified the formula but like you stated paraffin is the culprit - decent protection until it thermally breaks down.

Ams oil is superior - fake oil is the bomb - If your oil is staying that clean after 16,000 miles it not only means youv got one tight engine but that your oil is keeping it that way,
The most amazing engine iv ever ran across that way is actually in my brothers old Case skid steer - this is a diesel and its being ran on conventional Rotella T mineral - All diesels iv ever ran across soot up their oil in no time, this thing does not - not even when its due to change it, its as clean as a gas engines oil in really good shape at the end of its run interval, just a slight amber color, that blows me away, The piston rings are a near perfect seal in its combustion chamber to achieve this...

As good as synthetics are their are examples of mineral doing some amazing things - the fact of the matter is that if you use a high quality oil and keep it clean and have a high quality engine you will do very well --- You can run the best oil and have a crappy air filtration system and prematurely wear out your cylinder bores because you live and drive everywhere on dirt roads.

One of the biggest improvements for engine longevity has not just been engine oil, its been air filtration - no longer do we have a round dry filter mounted and sitting in the middle of a vibrating engine that does nothing more than "sift" the dirt through the paper element like your grandma used to sift flour - if particulates were to big to get through it would work them against each other or use them to cut through the filter medium till they could :rolleyes: What crap....
Now for the most part our filters are mounted on the vehicles body and many of the elements have a light coating of oil... This keeps engine oil cleaner better than the best engine oil filter ever could.

fasto
05-25-2009, 10:24 AM
so why change it then if it has not changed in color at all etc..

if it aint broke dont fix it right.. so help me understand this please iam interesed in hearing about this one,
For synthetic engine oils, I can offer one data point:
In 1993 I bought a new VW Corrado with VW's VR6 engine. It runs hot. Really hot. Always has. Oil temp ~250F on the highway, measured at the oil cooler outlet. I've had this car since new. I've always used Mobil1, with 10,000 to 12,000 mile oil changes. It's now got 210,000 miles. I replaced the oil pan gasket a couple weeks ago to fix a leak. The engine's bottom end looks new, oil pressure is unchanged from when it was new (presumably conrod bearings aren't excessively worn). Not a drop of sludge in the oil pan. Mind, the engine's top end is pretty worn (valve guides). I am very happy with my Mobil1 test.

That said, don't use engine oil on a machine tool. The additives in engine oil aren't needed and can be harmful. If way oil is not to your taste, use hydraulic oil. Hydraulic oil won't have the additives found in engine oil.
Mobil lists it's DTE "Circulating Oils" (hydraulic oils) as being suitable for hydraulics, ways, headstocks, and cutting oil.

Keep in mind that appropriate way oil for a 200-pound machine might not be appropriate for a 2,000 pound machine or a 20,000 pound machine. The smallest bearing surface on my 4,000 pound horizontal mill is around 100 square inches, so an oil with decent stick-slip properties is needed. Brown & Sharpe specify ISO32 hydraulic oil.

clint
05-25-2009, 11:01 AM
I have to put in a few comments here... We think we have come so far in air filtration ( not picking on you AK Boomer) however way back when they used a oil bath breather, those were some of the best air filters as far as filtering out debris/small particles. Also Pennzoil did have some problems as you mentioned, as did most other oils of that period, but they have come a long way in oil science, and now Pennzoil is one of the best oils on the market. In fact the oils are now rated by the starburst seal or whatever it's called by standards for oil to meet certain criteria.

Now on motor oils I think our biggest problems now is the removal of ZDDP, that's what made our early 90's and before motors last so long, push rods etc, now car manufactures have gone to roller low friction engines, so the oil manufactures remove the ZDDP which does not hurt the new cars such as my 02 Honda Accord V-Tech any at all, however older engines will suffer wear. If one really wants to compare oils, Shell Rotella T or regular, Dello 400 any heavy duty engine oil will out perform pretty uch all synthetic high priced oils, and stay well within the dino oil price range.

I ran Shell Rotella T 0-40w in a 97 Honda Accord and hit 40 MPG on road trips I was working on the road 115 miles each way to work a day, I was afraid the oil was to thick, however I have read over, and over this id not really problem, but I still stay on the safe side and use the recommended weight of oils. I do plan to try the Shell Rotella T again soon in the 97 accord to see if it was just a one time deal, or it was the oild that caused the fuel mileage increase.

Wow I really went astray on the top, and rambling in general, here is an outstanding site on oils in general http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=cfrm

saltmine
05-25-2009, 11:23 AM
I love it. For 40 years I made my living rebuilding engines and transmissions belonging to guys like you, airsmith282. They refuse to come into the twentieth century. These are the guys who like to use paraffin and mineral based oil, 160degree thermostats, and 90wt oil in their transmissions.
They're also the guys whose engines wear out at 30,000 miles, transmissions pack it in at 50,000 miles, and radiators get clogged up before most other cars are even out of warranty.

I make a practice of replacing my oil at 16,000 miles to replenish the additive package in the oil. The oil is doing it's job, of carrying contaminants to the filter, but as the oil is used in a car, the additives in the oil are consumed.
As I mentioned, the Las Vegas School District ran an International Harvester bus 275,000 miles on synthetic oil without changing it. They had a schedule where they would check and top up the oil periodically, and the oil filter was replaced every 20,000 miles. The condition and life of the oil was checked by pulling oil samples which were tested in a laboratory to assure the quality of the oil hadn't changed.

That's another thing you seem to have your head "up and locked" about, airsmith282. The "oil life" readout on your car. "Oil life" has nothing to do with the state of the oil in your engine. It is an alogirithm based on temperature, throttle position, speed, and time your engine management computer estimates how long you should run your oil. The formula is based on normal driving conditions and conventional mineral or pariffin based oils. My "oil life" readout comes on too, but I just reset it and continue on.

Yes, even though my oil still looks clean when I change it, cutting open the old oil filter gives graphic evidence that the oil was doing it's job, black as the ace of spades. The only way synthetic oils get discolored is from excessive heat, not contaminants.

As far as running heavier than called for oil in late model cars, Clint....don't do it. When I worked for the Sheriffs Department, we got numerous calls from other agencies about the Crown Victoria police car engines burning up bearings, cam chains and guides. We never had a problem. Why? We were using the recommended grade of engine oil in our cars, and many of the the other guys who were experiencing failures were running 15-40 oil. Later, I found out that many late model engines have very small oil passages to reduce the weight of the block castings, and high pressure pumps to deliver a lot of oil through them. When Ford recommended 5-20 wt oil, they were not kidding. Warranty has been denied because of the wrong oil..

rantbot
05-25-2009, 11:30 AM
The notion that automotive applications tell us anything useful about lubricants in general is probably the single greatest cause of the general confusion about oils for machine tools.

I have designed machinery for use in hard radiation environments, furnaces, deep sea applications, cryogenic environments, clean rooms, food service/washdown environments, vacuum chambers and space. These applications place some stringent demands on lubricants, and finding suitable materials can be a chore. It usually starts with guesswork - educated guesswork, but still guesswork - and proceeds to a testing program, which is the final step needed to convert guesswork into engineering.

Compared to any of the applications listed above, lubricating everyday machine tools is drop-dead easy. In my own tools I use a way oil for the ways (Vactra is easy to get and works fine), and everyday SAE 20 or 30 non-detergent oil for spur gears, screws, ball/roller/needle bearings, and unpressurized journal or sleeve bearings. That's it. Even that is a bit fussy - the SAE 30 works fine for ways, so the Vactra is optional. The SAE 30 is not such a good choice for a high-speed spindle or hypoid gears but I don't have any tools with such things so they're not a problem.

My choices are doubtless not the only ones - as I said, it's not a difficult environment, and the requirements on the lubricants are not exotic. Detergents, EP (extreme pressure) additives, etc just don't enter into consideration.

Automotive "gear oil" (usually with "EP" somewhere in the name) is the stuff for hypoid gears. It is not the right stuff for other types of gears. Hypoid gears have significant sliding action which is missing in spur gears, helical gears, bevel gears, etc. The EP additives keep the oil from getting wiped off the contact surface when the tooth loads are high. But they prevent things like the baulk rings and synchro cones in a regular manual automotive transmission from working properly, as those need a certain amount of friction to work at all. If you put "gear" oil in a manual transmission it won't shift. The lesson - just because something has gears in it doesn't mean that it should be lubricated with "gear" oil.

Peter S
05-25-2009, 10:13 PM
I haven't read all of the above, but I would think a machinery designer would ask an oil company to recommend a lubricant. And ask a few different oil companies while they were at it. Over time you will build up knowledge in any area if you follow this course (and reading and filing their product literature), however I would still be checking with oil companies on any particular application.

I have spent most of my working life in mechanical design, I make use of advise from outside specialists where ever possible.

QSIMDO
05-25-2009, 11:29 PM
Yeah, I was going to say something stupid like "consult an applications engineer with a lubricant manufacturer" but this has been far more entertaining.
;)

chief
05-26-2009, 07:27 AM
I have worked on jet engines(marine gas turbines), diesels, (Single cylinders Listers up to Sulzers). We did not change oil in either gas turbines or diesels
unless the spectrographic analysis said that the oil had become contaminanted. What we did do what to change filters frequently.
Oil will last a long time if the moisture is driven off and dirt is kept out of the engine, what the bogus testamonials don't tell you is that the air and oil filters are replaced at regular intervals. The navy doesn't change out oil in MRGs and CRP units unless there is a component failure, I have seen MRGs running 10 year oil but this oil is constantly run through a purifier, the temp is maintained at 180 deg and the filter and strainer units are serviced once or twice a day.
The color of used engine oil is an indicator of nothing, it changes color because of fuel soot. One of two things happens to engine oil, it either thickens because of suspended dirt and particulate matter or it thins out because of fuel contamination which then acts as wash instead of lubricant.

QSIMDO
05-26-2009, 10:58 AM
Sharples and DeLaval were indeed part of our daily lives as Enginemen in the Navy.
The oils we used in Buda's on up to Fairbanks 38D's were clear as water and stayed that way with a good spin.

Now there's a HSM project!
Build a oil seperator. :D

Mcgyver
05-26-2009, 11:05 AM
Motor oil should not be used in a machine tool. It's designed to hold debris and water in suspension until the oil filter can remove the debris and the heat of the engine can drive off the moisture.

is that so even with non detergent oil?

anyway, for prosperities sake, I was wrong in my extrapolation that because other Vitrea xx series = ISO xx then Vitrea 37 = iso 37. According to some guys on PM, shell changed the numbers which is why i'm not finding a Vitrea 37 listed and indeed Vitrea 37 an old series and = iso 100. I've used iso 68 hydraulic oil until i can find some 100

thanks for all the help

A.K. Boomer
05-26-2009, 11:13 AM
Now on motor oils I think our biggest problems now is the removal of ZDDP, that's what made our early 90's and before motors last so long, push rods etc, now car manufactures have gone to roller low friction engines, so the oil manufactures remove the ZDDP which does not hurt the new cars such as my 02 Honda Accord V-Tech any at all, however older engines will suffer wear.



This is of concern -- its a real problem with real consequences like cam lobe's totally disappearing and lifter faces as well ----- But just to throw in some perspective, If one educates themselves as to what engines are most at risk and what ones are not then it's just like anything else meaning the more you know about it the less concern you will have.

My bro who races is the first one I heard this through quite sometime back and he gave me a website to go to for verifying --- Its for real as many oil manufacturers are removing this additive including mobil which is what im currently running BUT - the example engine that they were using in the test was an older Porsche horizontally opposed air cooled --- Let me explain to you as I did in a reply to my bro as to why im not really concerned about this in my particular engine (92 toy-tercel)
As mentioned the Porsche is air cooled --- this is a factor that is huge right from the start as consistent and reasonable oil temps are critical for longevity --- now lets take the pushrod factor --- the loads are immense as compared to overhead cam, all that weight (the lifter/pushrod/rocker/valve/retainer/keepers) has to be returned in a set time frame so the valve springs have to be very stout -- not only that - even though an older Porsche engine is being used for the example it still is after all a porsche - which means its got good flow characteristics (big valves/and yet only two per cyl. = more weight) and also raps out in the RPM's (6,000 +) So when I mention stout valve springs I mean stout valve springs.
Last but not least I then introduce to you the nature of the horizontally opposed pushrod 4 cyl. engine where-as one cam lobe does the work load of two, so just as it gets done with one lifter it then goes into double time on the opposing side ---- this isnt just double the wear -- its far more as the single cam lobe has to eventually form wear patterns with two individual lifters, this in itself is also huge.
These engines are not only dinosaurs - with all the factors compounded I would rough estimate the the loads and wear factors to be somewhere in the neighborhood of 10 to 20 times that of a properly designed multi-valve overhead cam water cooled engine.
So - in summary ------- Im no more concerned about this additive getting yanked than I would be about not using hypoid gear oil in an application that does not require it --- get to know your engine and you will have no fear what to run as that's all that is required is knowledge, All you really need to know is if your engine is out of the stone age then run something that's designed to take care of all those engineering flaws that I just mentioned - And If your up to date with things then don't worry about it, Believe me - mobil isnt going to be putting out an inferior product that's locking up everybodys V-tech...

fasto
05-26-2009, 12:09 PM
Last but not least I then introduce to you the nature of the horizontally opposed pushrod 4 cyl. engine where-as one cam lobe does the work load of two, so just as it gets done with one lifter it then goes into double time on the opposing side ---- this isnt just double the wear -- its far more as the single cam lobe has to eventually form wear patterns with two individual lifters, this in itself is also huge.

If you have an engine of this type, and are concerned about the removal of the additive, you can always run aircraft piston engine oil (NOT turbine engine oil). Piston aircraft engines are usually opposed 4 or opposed 6 (with one opposed 8). Aeroshell oil and any other piston aircraft engine oil contains a Lycoming required additive that is rather like that mentioned above. I always ran Aeroshell 15W50 in my Lycoming O-360 and did not have a bit of cam trouble in 1200 hours.