Topics to be Discussed
Types of oils
Oils function or Job
API grades
SAE grades
ACEA specifications
OE specifications (GM, Ford, BMW etc.)
Determine
1. The recommended oil change interval
2. The recommended viscosity (SAE rating)
3. The recommended API rating
4. The vehicle specific specification of the oil
Explain the need for Lubrication system
Identify major parts
Explain engine oil classifications
Summarize the operation of engine lubrication system
List the different types of oil pumps
List different types of oil filters
Need for Lubrication system
Friction- force that opposes movement between any two objects in contact with each other
Two properties of FrictionHeatWear
Two kinds of Friction
Dry- When both materials are free from other materials
Wet- having other materials placed between them
• Fluid • Molecules
•Why is Friction Reduced?
• There is less “friction” between fluid molecules moving over each other than
between the two surfaces moving across each other.
The formation of an oil wedge in a plain bearing
Metal-to-metal contact Oil wedge supports load
•Connecting Rod Example
Engine oil Jobs
Lubricate engine moving parts
Cooling the engine
Seal- piston rings,valve stems
Clean- detergents hold impurities in suspension until filtered out
Oil Additives
Oxidation inhibitorsDetergentsDefoamersCorrosion inhibitorsViscosity improversAdditives are put in oil to help neutralize the acids from unburned gases from blowby
Additives Improve the Base Oil
Viscosity Index (VI) improver modifies the viscosity of the base fluid
so that it changes less as the temperature rises allows the lubricant to operate over a wider temperature range
Pour point depressant keeps the lubricant flowing at low
temperatures
Antifoam foam reduces the effectiveness of a
lubricant antifoams reduce/stop foaming when
the lubricant is agitated or aerated
•Additives Protect the Base Oil
• Antioxidants– slow down the breakdown of the
base fluid caused by oxygen (air) and heat
– oxidation is the main cause of lubricant degradation in service
• Oxidation of the base fluid causes:– acid formation (corrosion)– sludges, varnishes (blockages)
• Life of a lubricant in laboratory oxidation tests is often used to give an indication of service life
• Oxidation
•Additives Protect the Engine
• Rust inhibitor– inhibits the action of water on
ferrous metals (e.g. mild steel)
• Corrosion inhibitor– protects non-ferrous metals
(e.g. copper)
• Anti-wear additive– forms a protective layer on metal
surfaces to reduce friction and prevent wear when no lubricant film is present such as ZDDP.
• Extreme pressure additive– as for anti-wear additive but
functioning only when heavy loads and temperatures are encountered
• Roller bearing
wear• Gear tooth
wear
Additives
Up to 25% of the liquid in a typical quart of oil is additive. Additives are what really make the oil and determine its performance properties. Additives extend the viscosity range of the oil, allow it to withstand high pressures and loads, handle contaminants in the crankcase, and reduce friction for improved fuel economy.
Detergents
Modern motor oils also contain detergents and dispersants to reduce varnish and sludge formation to keep the engine clean.
Anti-oxidants to minimize oil burning when the oil gets hot. This also helps reduce the formation of varnish and carbon deposits inside the engine.
Corrosion inhibitorsRust and corrosion inhibitors are added to counteract the harmful effects of water, unburned fuel and exhaust gases that blow past the rings and enter the crankcase. This prevents the formation of acids that can pit bearing surfaces.Foam inhibitors are used to minimize the formation of air bubbles as the oil is churned by moving parts. Wetting agents help the oil stick to hot surfaces so it doesn't run off and leave the metal unlubricated and unprotected.
Anti Wear/ Pressure
Anti-wear and "extreme-pressure" additives. These include zinc and phosphorus that provide wear protection when metal touches metal. Some racing oils typically have a higher dose of zinc to provide extra protection in high revving, high load applications.
Oil Viscosity
Viscosity – measure of a fluids ability to resist flowing
Viscosity Index
One of the most important additives is "Viscosity Index (VI) Improvers". These help the oil maintain a consistent viscosity as temperature and load change.
"Pour point depressants" are also used to prevent the oil from thickening at low temperature for easier starting
Polymers
Polymers- are a hydrocarbon molecule that make the oil thinner when cold and thicker when hot
Polymers are referred to as- multi-grade, multi-weight, all-season, all- weather
How to choose oil viscosity
Always follow manufacturers recommendation for viscosity
READ THE BOOK!!! Owners Manuel
As a rule, overhead cam (OHC) engines typically require thinner oils such as 5W-30 or 5W-20 to speed lubrication of the overhead cam(s) and valve-train when the engine is first started. Pushrod engines, by comparison, can use either 5W-30, 10W-30 or 10W-40.
Viscosity
• © epc graphics
Viscosity is a lubricant’s resistanceto flow.The viscosity of an industrial lubricant is normally given in: cSt (centistokes) or mm²/second
measure of kinematic viscosity
Viscosity is the main feature which influences the efficiency of lubrication
Do customers know?Do service technicians know?
SAE=? (Society of Automotive Engineers)
API=? (American Petroleum Institute)
ILSAC=? (International Lubricant Standardization and Approval Committee)
ACEA=? (Association des Contructeurs European d’Automobiles)
Need to know or nice to know?
American Petroleum Institute (API)
The "service rating" of motor oils is classified by the American Petroleum Institute (API). The program certifies that an oil meets certain OEM quality and performance standards. The service rating is shown in the API "Service Symbol Donut" on the product label. There may also be an "API Certified for Gasoline Engines" seal on the label.
API Label
API RatingsGasoline Engine Ratings
SA-SJ=older and now obsolete ratingsSL-2001-2003SM-2004+SN -October, 2010
Diesel Engine RatingsCA-CC=obsoleteCurrent ratings = CF-4 (four cycle); CG-4 and CJ-4 (low ash) (2007+ Engines using ULSD)Need to know stuff
API Service LabelsThe latest service category rating for gasoline engines is "SN", introduced in 2010 and newer engines. SN is backwards compatible and can be safely used in older engines. But the opposite is not true. Older obsolete service classifications (SH, SG, SF, etc.) may not meet OEM lubrication requirements for newer engines. Likewise, API SL oils should not be used in 2005 and later vehicles, and SJ oils should not be used in 2001 and newer vehicles.
ILSAC RatingsILSAC=International Lubricant Standardization and Approval
Committee
GF-1-First used in 1993GF-2-updated in 1997GF-3-Updated in 2000GF-4-Updated in 2004GF-5-Out now for use in 2011+ engines“Star Burst” is always on the front of the container.GF means gasoline fueled enginesStar Burst indicates that the oil is of a good quality and meets the GF rating. Usually, only 0W, 5W and 10W oils will have this symbol.
• Nice to know stuff……….but…..
ILSAC Standards for Passenger Car Motor Oil
GF-5Introduced in October 2010
For 2011 and older vehicles, designed to provide improved high temperature deposit protection for pistons and turbochargers, more stringent sludge control, improved fuel economy, enhanced emission control system compatibility, seal compatibility, and protection of engines operating on ethanol-containing fuels up to E85
GF-4 Obsolete Valid until September 30, 2011. Use GF-5 where GF-4 is recommended
GF-3 Obsolete Use GF-5 where GF-3 is recommended
GF-2 Obsolete Use GF-5 where GF-2 is recommended
GF-1 Obsolete Use GF-5 where GF-1 is recommended
SAE Grades
SAE = Society of Automotive Engineers
5W = The “W” means winter and the oil is tested at -30 C (-22F)
SAE 5W-30 = The “30” is the viscosity measured at 100 C (212 F)
Need to know stuff
• COLD (WINTER) HOT
• -22OF 212OF
• THE “W” DOES NOT STAND FOR “WEIGHT”
High-Mileage Oil
Usually higher viscosity and therefore can not meet ILSAC GF-4 ratingHas esters to swell sealsTo be used in engines with higher than 75,000 milesDoes not have the energy rating of conventional oils
Diesel Labels
For diesel engines, API has a separate rating system. The current category is "CI-4" (introduced in 2002 for newer diesels that have exhaust gas recirculation). The previous CH-4 (1998), CG-4 (1995), and CF-4 (1990), can all be used in older four-stroke diesel engines. CF-2 (1994) is the API classification for two-stroke diesels.
ACEA Diesel RatingsB1-Low viscosity passenger vehicle indirect-injected diesel enginesB2- Passenger vehicle indirect-injected diesel engine. Low viscosity.B3-High performance indirect-injected diesel engines; extended oil change intervalB4-Direct-injected diesel enginesB5-Low viscosity and extended oil change intervalNice to know stuff
What is different with European ratings?
Usually very high viscosity index (VI) meaning that the SAE grade is broad; often requiring SAE 10W-50 or 5W-40Extended oil change intervals requiring a robust additive packageLow SAPS (Sulfated Ash, Phosphorous and Sulfur)Higher HTHS (High temperature/ high shear rate viscosity)
Why to change oil?Regardless of an oil's API service rating or additive package, all motor oils eventually wear out and have to be changed (actually, it's the additives that wear out more so than the oil). As the miles add up, motor oil loses viscosity and gets dirty. The oil no longer has the same viscosity range it had when it was new, and it contains a lot of gunk (moisture and acids from combustion blowby, soot, dirt and particles of metal from normal wear). You can't really tell much about the condition of the oil by its appearance alone because most oil turns dark brown or black after a few hundred miles of use.
The oil filter will trap most of the solid contaminants, and the Positive Crankcase Ventilation (PCV) system will siphon off most of the moisture and blowby vapors -- if the engine gets hot enough and runs long enough to boil the contaminants out of the oil. Even so, after several thousand miles of driving many of the essential additives in the oil that control viscosity, oxidation, wear and corrosion are badly depleted. At this point, the oil begins to break down and provides much less lubrication and protection than when it was new. If the oil is not changed, the oil may start to gel or form engine-damaging varnish and sludge deposits -- and eventually cause the engine to fail!
Oil life
Oil life depends on many factors including driving conditions (speed, load, idle time, etc.), environmental factors (temperature, humidity, airborne dirt), and engine wear.
Extended oil life
Extended oil change intervals of 7,500 or 10,000 miles or more are based on ideal operating conditions, not the type of short trip, stop and go driving that is typical for many motorists. Consequently, most drivers should follow a "severe" service maintenance schedule rather than a "normal" service schedule to protect their engines.
Severe Service
* Most trips are less than 4 miles.* Most trips are less than 10 miles when outside temperatures remain below freezing.* Prolonged high speed driving during hot weather.* Idling for extended periods and continued low speed operation (as when driving in stop-and-go traffic).* Towing a trailer.* Driving in dusty or heavily polluted areas.
Synthetics OilsSynthetic oils are oils that are refined to a much higher degree than ordinary oils. Synthetic oils are premium oils that generally have greater viscosity stability, lower pour points and can withstand higher operating temperatures. Synthetic oils improve cold starting, reduce friction, reduce oil consumption and improve fuel economy and performance -- but they typically cost about three times as much as regular motor oil.Synthetic oils are a good upgrade for most engines, but are not recommended for breaking-in newly rebuilt engines
Some suppliers of synthetic motor oils say the higher cost of the premium quality oil can be offset by extending oil change intervals. But this would depend on the operating conditions, age and condition of the engine.
SYNTHETIC OILS •MINERAL OILS
• Large Molecules thicken at low temp
• Small molecules
• vaporize at high temp
• All molecules same size
• H-C-C-C-C-C-H
• H• H• H• H• S
• H • H• O • N• H• Impurities oxidize
• C10H20
• C10H20
• C10H20
• C10H20
What About Older Engines?
If flat-bottom (non-roller) lifters are used then a ZDDP additive may be needed:
During break-in During service
ZINC or ZDDP Additives
The phosphorous content of ZDDP= Zinc Dialkyl Dithiophosphates (commonly called zinc and/or phosphorous or ZDP)
Engine oil had about 1200 ppm zinc prior to 2001
In 2001 the zinc was reduced to 1000 ppm and in 2005 reduced again to the current 800 ppm
These are typical zinc levels; API ratings do not specify the zinc content, just oil performance
How to change oil and filter
* Drain the oil while it is hot. Contaminants will be in suspension and drain more easily from the engine.* Always replace the filter when changing the oil* Wipe some oil on the filter gasket so the seal won't stick or tear.* Hand tighten the filter about 1/2 to 3/4 of a turn after the gasket makes contact. Over-tightening may damage the threads or gasket, and make the filter difficult to remove the next time the oil is changed. Under-tightening may allow the filter to work loose and leak.
* If the oil is badly contaminated or sludged, the crankcase should be cleaned and flushed before the engine is refilled with oil.* Always check the oil level after refilling the crankcase. Start the engine, then shut it off and check the oil level after several minutes. It should be at the full mark on the dipstick. Most engine hold about four quarts of oil, plus half a pint to almost a quart for the filter (depending on the size of the filter). Overfilling can cause oil foaming and leaks. Under-filling may cause a loss of oil pressure and engine damage!_
Testing Oil
oil sample to lab for analysis
For example:
Blackstone Laboratories-$22.50 www.blackstone-labs.com
Nice to know
Oil Test ResultsSpectral Exam: Establishes the levels of wear metals, silicon, and additives present in the oil. Also checks for coolant.
Note: Silicon = dirt; not sealer
Viscosity: Determines the grade of oil.
Insolubles: Quantifies the percentage of solids present in the oil.
Flash Point: Determines the flash point of the oil to determine whether any contamination is present in the oil (such as fuel)
Understanding the Lab Report
Aluminum: Pistons, bearings, cases (heads & blocks) Chromium: Rings, a trace element in steel Iron: Cylinders, rotating shafts, the valve train, and any steel partCopper: Brass or bronze parts, copper bushings, bearings, oil coolers Lead: Bearings Tin: Bearings, bronze parts, piston coatingsMolybdenum: Anti-wear additive, some types of rings Potassium: Antifreeze inhibitor, additive in some oil typesBoron: Detergent/dispersant additive, antifreeze inhibitorsSilicon: Airborne dirt, antifreeze inhibitorsSodium: Antifreeze inhibitors, additive in some gasoline engine oils. Calcium: Detergent/dispersant additiveMagnesium: Detergent/dispersant additive
Nice to know
Frequently Asked Questions
Question: Can you go back to using conventional oil after using synthetic?
Answer: Yes. By law, all oil is miscible meaning that it can be mixed.
Disposal of used filters
Filters are crushed and placed in 55 gallon barrel
Oil is placed in 55 gallon drums and recycled
Three types of Lubrication Systems
Full pressure system
Splash system
Combination pressure-splash
Full pressure system
Draws oil from oil pan by means of oil pump. Pump forces oil through drilled and cast passages called oil galleries to the crank and camshaft journals
Splash System
Supplies oil to moving by adding dippers to the bottom of the connecting rod
Used primarily on small one cylinder engines
Types of oil pumps
Gear pump-
Rotary- pump
Vane pump-
Gear and rotary are the most widely used
Gear Pump
Gear Pump is efficient and produces high pressure and flow when needed
Rotary pump
Vane Pump
Oil Pump Pressure relief valve
An oil pump in good condition will produce pressures far beyond those necessary for lubrication.
Pumps are designed to flow large quantities of oil, but when the useable pressure limits are reached a pressure relief valve opens and returns oil back to sump
Relief valve
Relief valve
The pressure relief valve will allow the pressure reaching the bearings to remain at a predetermined level however by varying spring tension the pressure can be raised or lowered
Oil Pump drive
Oil Galleries
http://www.youtube.com/watch?v=j-IHMv6uhgo&feature=related
Four styles of lubrication
Wet sump
Dry sump
Splash
Total loss
Wet Sump
Wet Sump engines use an oil pan (sump) to store the oil at the bottom of the engine and use an oil pump to pump the oil to where it is needed in the engine. Some engines of this type will have a removable oil pan and some won't. Most Wet Sump engines have a plate under the crankshaft and over the oil. This is to prevent friction losses from the oil splashing on the spinning crankshaft. This seems to be the most popular oiling system.
Wet Sump
Dry Sump
Dry Sump engines carry their oil in an oil tank that is separate from the engine. This can be an actual tank or inside of the tubes of the frame. This engine lubrication type uses two oil pumps. One to pump oil to the engine, where it lubes everything and then drops to the bottom of the engine. From there, the second or scavenge pump pumps the oil back to the oil tank. Sometimes the scavenge pump also pumps oil to the transmission, valves and other places in the engine. The scavenge pump is twice as big as the main oil pump. If you look at the oil return pipe, when the engine is running, it will be spurting oil. This is normal. Dry Sump engines tend to back flow oil into the lower part of the engine when they sit for long periods of time. Because of this, you will need to run the engine for about five minutes before checking the oil. If you are not sure whether the engine has any oil or not, add a pint and then start the engine. If the oil level rises you can siphon some out. If not, add some more oil. At worst the oil will overflow, which is better then no oil !
Dry Sump
SplashSplash Lubrication is pretty primitive. A hook, cast or bolted onto the crankshaft, dips into the oil in the sump and splashes it around the inside of the engine.
Total Loss
This was used on motorcycles back in the early 1900s. Early motorcycle engines had plain babbet bearings or roller and needle bearings or a combination of both. Oil, oilpumps, babbet and everything else were all kind of new back then and not as good of quality as we have today. Because of this, high output engines used roller and needle bearings. The engines had hand pumps on their oil tanks. When you started the engine you gave 'er a shot of oil. Every so many miles you would give the engine another stroke of the pump. The engine used up the oil and got more clean, fresh oil to the bearings with each stroke of the pump. The engines had sumps and these where filled with oil to start with and splash lubrication took care of the rest of the engine. This gave lots of clean, fresh oil always going through the engine. Sometimes the engines had a Drip feed Lubricator, in addition to the hand pump. One pump of oil every eight to ten miles at 20 MPH was deemed sufficient. At 30 MPH you needed one pump every five or six miles. The Drip Feed should be set at 8 drops per minute, just in case you wanted to know. I don't think you will run into too many of these machines !
Hydraulic valve lifters
1. Quieter2. Low maintenance3. An ability to adjust for thermal expansion of the engine4. Built in shock absorber, eases stress on valve train5. "Bleed Rate" can be designed to accommodate different engine RPM ranges
Hydraulic Lifters
Oil under pressure is forced through the tappet when the valve is closed this extends the plunger in the tappet so valve clearance is eliminated.
When the camshaft lobe moves around and starts to raise the tappet oil is forced upward in the lower chamber of the tappet this closes the ball check valve and oil cannot escape thus opening the valve on a column of oil.
Oil Filtration
Many materials have been used to find the medium to filter oil such as cotton waste, plant fibers, metal clay and paper
Two types of filters
Depth filters-
Surface filters-
Depth filters
Depth filter operation
Depth filters
The annular ring of the cylindrical filter receives the "dirty" oil and under pressure infiltrates to the core which is the "clean" side of the filter. When excessive pressure exists across the filter medium a bypass valve opens permitting dirty oil to by-pass the filter medium preventing oil starvation at the bearings. Some oil filters have the by pass on top near the inlet (as illustrated), other designs have the by pass on the far end of the element or the bottom.
Oil filter bypass valve
Two types of filter systems
Full flow filter system- used on modern engines, entire output of the pump goes through the filter
Bypass Filter system- (Old way) only filters some of the oil
Crankcase Ventilation
Blowby- exhaust and unburned gas that seep past the piston rings and into the crankcaseUnless vented the pressure will force oil to escape past oil sealsPCV- Positive crankcase ventilation uses engine vacuum to draw fresh air through the engine
PCV testing
With the engine idling at normal temperature, pull the PCV valve from the valve cover and put your finger over the end to determine if it is pulling a vacuum. Be careful, as the valve may be hot. If no vacuum is detected, remove the valve from the hose to see that there is vacuum in the hose. If there is vacuum in the hose, the valve is defective and needs to be replaced. If there is no vacuum in the hose, and the hose does not appear to be defective,
Dipstick used to check amount of oil in crankcase
sump
Cooling the oil
Most heat from the oil is dissipated through the thin sump to the surrounding air, some oil pans have fins to help dissipate heat
Auxiliary oil cooler- some are in the radiator, external oil coolers
Oil cooler