Internal combustion engine?

[sorayahya]

What are the uses of mineral oils and self contained lubrication system in internal combustion engine?

Please answer fast Its urgent

 

[brewnog]

To lubricate, to cool, and to clean. And in some cases as hydraulic fluid too (tappets, valve actuation, fuel injection, viscous drives etc).

A more detailed question might get some more detailed answers. And how urgent can it really be?

 

[Averagesupernova]

I would say it is urgent because it sounds like homework that is soon due.

 

[sorayahya]

Well its not homework I just need an answer fast so that I can continue my work.

 

[sorayahya]

To lubricate, to cool, and to clean. And in some cases as hydraulic fluid too (tappets, valve actuation, fuel injection, viscous drives etc).

A more detailed question might get some more detailed answers. And how urgent can it really be?

Ok

What are the uses of mineral oils in the internal combustion engine?

What are the uses of self contained lubrication system in internal combustion engine?

But I need like a full description maybe a link to an article and some pictures etc.

 

[Ranger Mike]

see post in General Engineering titled Internal Combustion Piston Lubrication
Old Apr24-11, 09:56 PM

 

[sorayahya]

see post in General Engineering titled Internal Combustion Piston Lubrication
Old Apr24-11, 09:56 PM

thanks that should answer my second answer but I'm still stuck with the first question

What are the uses of mineral oils in the internal combustion engine?

 

[Unrest]

What are the uses of mineral oils in the internal combustion engine?

[/quote]

Brewnog answered that by saying what engine oil does.

Don't forget diesel fuel is a mineral oil, so it's used as fuel too.

 

[brewnog]

Asking the same question again but more loudly wasn't quite what I was getting at when I said "more detailed"...

Glad to have helped.

 

[Ranger Mike]

Maybe it is a dictionary question ..am i getting mineral oil mixed up with fossil based petroleum oil? the only mineral oil use i know of is a small amount in the air conditioning to keep the seals lubricated...brewnog..am i thinking fuzzy on this???

 

[Unrest]

Maybe it is a dictionary question ..am i getting mineral oil mixed up with fossil based petroleum oil? the only mineral oil use i know of is a small amount in the air conditioning to keep the seals lubricated...brewnog..am i thinking fuzzy on this???

Oh! Who would have realized mineral oil isn't just any old oil you find in the ground :P But seems like the OP isn't really sure what it is either.

 

[sorayahya]

No I'm asking what is the mineral oil's job in the Internal combustion engine

 

[xxChrisxx]

No I'm asking what is the mineral oil's job in the Internal combustion engine

Mineral oil does the job of any other oil in an engine. Lubricates stuff, or is used as hydraulic fluid. The mineral aspect just tells you where the oil came from (distilled crude). Mineral oil has been replaced in newer cars by fully synthetic oil. Most modern engine's don't use mineral oil at all.

Now stop asking the same question over and over.

 

[brewnog]

Mike, I read mineral oil to be a lube oil constituting something refined from crude oil (compared with synthetic or a semi-synthetic blend). See what you're getting at with regard to air conditioning, but I don't think that's what the OP is asking.

Then again, we've just been asked the same question four times, so I guess the OP is just reading from his homework paper without having a clue what he's looking for. Never mind.

 

[Ranger Mike]

Well you guys made me dig out my notes from the car hauler..
engine oil does three things, cleans, lubricates and cools.

I went through this research last year when we had over heating problems on the Formula Car, One area overlooked was the type of oil we were using..We always break in the engine with Vavoline 50 w oil...readily available at NAPA, Autozone..any auto jobbers counter.

Now hear this--- Motor oil manufacturers recommend break in with fossil based petroleum oil and NOT SYNTHETIC...that should tell you something...

We use petroleum 10w50 motor oil on break in to ensure proper piston ring seating. If you allow 1500 to 2000 miles in a street engine or 20 to 30 minutes on the dyno at low rpm, the rings will have had sufficient time to seat and the high initial break-in wear will have occurred. After good ring seating we used Redline oil ( Group 5). It is a true hybrid ( at $8.00 a quart)


There are five specific categories of base oils. These categories define the type of base stock the oil is formulated from. The categories are as follows. Note that the base oil group category is followed by the manufacturing method (in bold print) and then a description of the oil characteristics for each category.


Group I - Solvent Freezing: Group 1 base oils are the least refined of all the groups. They are usually a mix of different hydrocarbon chains with little or no uniformity. While some automotive oils on the market use Group I stocks, they are generally used in less demanding applications. Group I base stocks contain less than 90 percent saturates and/or greater than 0.03 percent sulfur and have viscosity index greater than or equal to 80 and less than 120.


Group II - Hydro processing and Refining: Group II base oils are common in mineral based motor oils currently available on the market. They have fair to good performance in lubricating properties such as volatility, oxidative stability and flash/fire points. They have only fair performance in areas such as pour point, cold crank viscosity and extreme pressure wear.Group II base stocks contain greater than or equal to 90 percent saturates and less than or equal to 0.03 percent sulfur and have viscosity index greater than or equal to 80 and less than 120.


Group III Hydro processing and Refining: Group III base oils are subjected to the highest level of mineral oil refining of the base oil groups. Although they are not chemically engineered, they offer good performance in a wide range of attributes as well as good molecular uniformity and stability. They are commonly mixed with additives and marketed as synthetic or semi-synthetic products. Group III base oils have become more common in America in the last decade. Group III base stocks contain greater than or equal to 90 percent saturates and less than or equal to 0.03 percent sulfur and have viscosity index greater than or equal to 120.


Group IV -Chemical Reactions: Group IV base oils are chemically engineered synthetic base stocks. Polyalphaolefins (PAO's) are a common example of a synthetic base stock. Synthetics, when combined with additives, offer excellent performance over a wide range of lubricating properties. They have very stable chemical compositions and highly uniform molecular chains. Group IV base oils are becoming more common in synthetic and synthetic-blend products for automotive and industrial applications.
Group IV base stocks are polyalphaolefins (PAO).


Group V - As Indicated: Group V base oils are used primarily in the creation of oil additives. Esters and polyolesters are both common Group V base oils used in the formulation of oil additives. Group V oils are generally not used as base oils themselves, but add beneficial properties to other base oils.

Note that the additives referred to in the Group V description are not aftermarket type oil additives. The additives referred to are used in the chemical engineering and blending of motor oils and other lubricating oils by the specific oil company that produces the finished product. Group V base stocks include all other base stocks not included in groups I, II, III or IV.

Bottom line is - when you have very close tolerances, high heat potentials , petroleum based oils molecular structure breaks down more quickly than synthetic molecular chains.
ifin you race a car, you better use an oil cooler..period...no exceptions...

 

[AlephZero]

Now hear this--- Motor oil manufacturers recommend break in with fossil based petroleum oil and NOT SYNTHETIC...that should tell you something...

Well, that depends on the type of car. The last new European can I bought had no requirement for a first service and oil change at 1000-2000 miles, and uses synthetic. It's just coming up to its first scheduled oil change at 18,000 miles. It's been topped up about half a liter (call that a pint) over that mileage, and the stuff on the dipstick looks almost as clean as when it was brand new...

I suppose it's possible that the makers fullly run in every new engine on a dyno, but I doubt it for a cheap mass produced compact car. It certainly took a couple of thousand miles for the engine to be running freely (the MPG improved by about 10% over that period), and that's what the sales people had told me to expect.

Another issue for road cars is oil contamination of modern "3-way" catalytic converters by burnt oil fumes. AFAIK that is a "no-no" for using non-synthetic oils, regardless of their other qualities.

 

[Ranger Mike]

granted that the new car uses synthetic oil but you do not know absolutely that it came from the factory with synthetic oil..unless you tested it and i would bet that it did come with fossil petrol oil..

but you are the owner and if it says 18000 for first oil change..you ought to know...seems like a whole lot of miles for first flush...a lot of casting chips, machining filings etc...still remain in the case regardless of care take to clean prior to assembly..
good information..thanks

 

[Ranger Mike]

As i was flogging the Formula Car for the first race event next week..i took a break and was thinking about that 18,000 mile interval...I looked up an old adviser and submit the following for thought..

Oil
What motor oil is best for my aircooled Porsche?
(or any high performance engine)
by Charles Navarro
Last Updated 03/30/09​

The purpose of proper lubrication is to provide a physical barrier (oil film) that separates moving parts reducing wear and friction, but there are many surfaces within an engine that operate with metal-to-metal contact, again popular belief, that are very highly dependant on a strong and robust anti-wear film. The top piston ring operating in sliding contact with the bore operates in a mixed lubrication regime consisting of both boundary (metal-to-metal direct contact) as well as hydrodynamic (oil film between moving surfaces) lubrication. The majority of non-corrosive wear occurs where boundary lubrication exists, especially at cam lobes, tappets, cam follower/buckets, and rockers. Oils contain dispersants, friction modifiers, viscosity modifiers, anti-foam, anti-corrosion, antioxidant and anti-wear additives, all of which can affect the strength and durability of anti-wear films. The focus of this study is on the levels of zinc and phosphorus found in motor oils and their interactions with other additives, more exactly, the zinc (Zn) and phosphorus (P) that makes up the anti-wear additive ZDDP, zinc dialkyl dithiosphosphate, as the ZDDP level is causing concern for all older engines, including aircooled Porsches, with modern oils.

What general characteristics make motor oils specifically well suited to an aircooled or other high performance engine? Aside from recommendations issued by Porsche, what makes a good oil? These oils must be thermally stable, having a very high flashpoint, low noack volatility, and must “maintain proper lubrication and protect vital engine components under the extreme pressure and the high temperature conditions” found in aircooled Porsches. Many engine builders recommend 15w40 viscosities below 90F ambient air temperatures with 20w50 for hotter climates above 90F average ambient temperatures. Porsche recommends and uses Mobil 1 0w40 as a factory fill in new vehicles and their 15w50 has been a popular choice used by many in the aftermarket in aircooled models. What was once considered a 'safe' oil is no longer as many of these lubricants have been reformulated for many reasons, not limited to allow for protection of emissions controls and for longer drain intervals.

Even prior to the introduction of the API's SM standard, there was concern that current API SL standards from back in 2003 may inhibit the backwards compatibility of motor oils, specifically referring to the limitation of ZDDP, which is "the most effective combined anti-wear and anti-oxidant additives currently available." SAE 2003-01-1957, Effect of Oil Drain Interval on Crankcase Lubricant Quality, Shell Global Solutions. The authors continue to state that oils are required to provide longer protection in severe operation but that an oils performance is "limited by environmental considerations." Furthermore, they state that it is hard to predict the effects of these reformulated oils in just a single oil change and may only be evident over an engine's lifetime. It is hard to know the full extent of the potential damage these new SM oils will have on our performance engines so chose your lubricants carefully.

Porsche’s recommendation in hand, our initial analysis from 2005 and 2006 and from virgin oil analyses going back to the 1990s, we found that then recent SH/SJ formulations of Mobil lubricants tested, including Mobil 1, have had higher Zn and P content than SL or current SM formulations. Even current "re-introduced" formulations are not the original formulations many shops and owners were used to. Aside from reduced Zn and P levels (now restored in certain products), many products with "adequate" Zn and P still use high levels of Ca detergents, well documented in various SAE publications as known for causing more wear than Ca/Mg or Ca/Mg/Na detergents, as previously used in oils like Mobil 1 15w50, back when it was API SH/SJ rated and prior to reformulation. This confirms the industry wide trend of the reduction of Zn and P from motor oils and switch to Ca-based detergents, with the eventual reduction to 0.06-0.08% or even worse, the elimination of these additives, which are essential to an aircooled Porsche engine's longevity. Depending on how detergent an oil is and which detergents are used, optimal Zn and P levels can range from 1200 to 1500 ppm, lower detergency oils requiring less Zn and P.

Many Porsche repair shops have acknowledged that these newest SM and CJ-4 motor oils are not sufficient for protecting any Porsche engine, including newer water-cooled ones. With longevity and the protection of vital engine components in mind, many shops are recommending non-approved motorcycle or racing oils, or the addition of oil supplements at every oil change, for their higher levels of protection. On newer water-cooled engines where Mobil 1 0w40 is recommended, a simple change to an oil with CJ-4 rating or preferably an oil with SL or CI-4 rating as well as a viscosity of 5w40 rather than 0w40 are two changes that can be done in addition to more frequent oil changes to ensure longevity of newer engines.

Oil companies have been cutting back on the use of Zn and P as anti-wear additives and switching to alternative zinc-free (ZF) additives and ash-less dispersants in their new low SAPS oils since Zn, P, and sulfated ash have been found to be bad for catalytic converters. One such ZF dispersant/anti-wear additive is boron, which does not foul the catalysts in the particulate emissions filters or catalytic converters. For most owners, the reduction in longevity of a catalytic converter is a small price to pay considering the many thousands of dollars it costs to properly rebuild a Porsche engine. It is worth noting that most Porsches have lived the majority of their lives with high Zn and P oils as found in API SG-SJ oils as late as 2004, and we never hear of problems with their catalytic converters.

In addition to protecting emissions controls, there are many other design considerations in formulating engine lubricants, which include improving fuel economy and longer drain intervals. Many believe that the EPA has banned zinc and phosphorus in motor oils. This is not true. In response to modern engine design and longer emission control warranties which are required by the EPA, manufacturers have turned to reformulation of oils to do this, as well as to improve fuel economy by reducing fiction. High friction can result in areas with boundary lubrication or where high viscous friction forces and drag may occur with hydrodynamic lubrication in bearings. The use of friction modifiers, such as moly (there are many different species of Mo-based friction modifiers, help to reduce friction in metal-to-metal contact with the formation of tribofilms characterized with their glassy, slippery surfaces. Lower viscosity motor oils are key to increasing fuel economy by their reduction in drag where high viscous friction occurs in hydrodynamic lubrication. While lower viscosities improve fuel economy greatly, they also reduce the hydrodynamic film strength and high temperature high shear viscosity of the motor oil, factors both of which are key to protecting high performance engines, especially aircooled ones.

However, it is worth noting that these new API guidelines do not need apply to “racing,” “severe duty,” or any motor oils that do not carry an API “starburst” seal or clearly state for off-road-use only. Motor oils meeting “Energy Conserving I or II” standards should be avoided as well as those with an API SM or ILSAC GF-4 classifications. The European ACEA A3/B3 "mid-SAPS" classifications, which place a cap on P levels at 0.10-0.12% but allow for higher Zn levels, to be better in taking into consideration wear and engine longevity, setting much lower wear limits, while still limiting emissions and protecting emissions control devices. The current ACEA A3/B3 classifications require higher high-temperature high-shear (HTHS) viscosities, stay in grade sheer stability, and tighter limits on evaporative loss (noack volatility), high temperature oxidation, and piston varnish. This makes oils meeting these ACEA standards that much better for your Porsche, especially since wear limits are much more stringent for valve train wear, 1/6th to 1/4th the wear allowed in the sequences for API's newest SM or CJ-4 standards. Of particular interest is the upcoming ACEA E9 which will incorporate some of the improvements in the CJ-4 standard along with higher Zn and P, making these mid-SAPS oils an excellent choice for older legacy engines.

Failure to use the right oil, use proper filtration, or observe proper changing intervals can affect the performance of even the best motor oil. This also includes changing the oil too often (needlessly bad for the environment and your wallet) or not often enough. Against conventional wisdom, engine wear decreases as oil ages to a certain extent, which means that changing your oil more frequently actually causes engine wear; these findings were substantiated by studies conducted by the auto manufacturers and petroleum companies, leading to standard drain intervals increased from 3,000mi/3 months to 5,000-7,500mi/6 months in most domestic vehicles, using mostly non-synthetic oils. Based off of extremely long drain intervals recommended by most European manufacturers, some in excess of two years and 20,000 mi, some users have found it best to reduce those intervals by half or even a quarter. Porsche for the 2008MY has reduced their extended drain intervals significantly to one year/12,000 mi, which is actually less miles than Porsche recommended back in the 1990s with 964 and 993 based aircooled 911s. Based on UOAs provided to us by our customers, new Porsche owners should consider reducing their drain intervals further to no more than 9,000 mi or one year and some shops recommend changes every 5,000-6,000 mi or six months (an interval we run in all our vehicles). Also, remember, Porsche drain intervals are based off a fill of min. 10 quarts, so engines with smaller sumps have to run shorter drain intervals!

Vehicles with track time or sustained high oil temperatures or RPMs should have their oil changed after every event (or every other event). This translates to a total of about 10 hours maximum combined engine operation, with vehicles with 12 qt or higher oil capacities- engines with smaller capacities must be changed more often. Vehicles subjected to very short drives or sustained operation in heavy traffic should indeed be serviced more often. Likewise, vehicles not driven often but driven hard a few times a year can probably go a year between oil changes, but that doesn't mean you shouldn't use a good oil! Regular used oil analysis is the best way to determine ideal drain intervals for your driving habits - one good rule of thumb I have seen quoted is to change the oil with the TBN (total base number) is reduced by 50% of the original total (requiring you to also know your oil's virgin TBN). Another common recommendation is to change the oil once it's TAN (total acid number) equals the TBN. Other factors to consider are fuel dilution and shearing out of grade when determining your drain interval. With this knowledge in hand, using a quality motor oil with proper filtration and regular service is the best thing to do for your engine and to protect your investment.

Any information you may receive related to this web site is provided merely as friendly suggestions, not as expert opinion, testimony or advice. Neither LN Engineering nor Charles Navarro endorses or sponsors any information, products or methodologies you may find herein. - Sorry for the legal mumbo-jumbo!

thanks Chuck!!