The iso egd is not a ashless formulation. It is currently the most stringent cert in the world in terms of high temp cleanliness and scuff resistance. It is light years ahead of tcw3.
Ted, the iso cert does have a low smoke test, but it is not emmisions driven as you suggest.
I have a 02 cr500 af with about 75 hours on it useing a iso egd oil. I just replaced the piston and rings. It did not have any of the signs of blowby that the your pics had. The piston skirts as well as the head, exhaust port where clean and the motor still had comp within 20% of stock. The motor had the original plug in it and was run on a 32:1 ratio. We have lots of sand in MI also and I have no scratches on my piston. The schaefers oil my be great stuff in its intended application, but a high output bike is not it.
WATER-COOLED vs AIR-COOLED LUBRICANT REQUIREMENTS
Background:
The types of performance required of any two-cycle engine oil (Table 1) has not changed over time; only the degree of anti-seizure performance, piston cleanliness, smoking, etc. New generations of two-cycle oils are designed to satisfy higher demands presented by newer high-output engines.
The choice of oil for the American two-cycle engines has been largely controlled by marketplace availability. In the 1960's motorcycle engine oils were used with great success. The introduction of injectors in outboards, lighter two-cycle oils were needed for fluidity and BIA (now the NMMA) TC-W® oils were introduced.
Table 1 - Required Performance of Two-Cycle Engine Oils
Provide excellent lubricity. Reduce wear on rings and cylinders. Prevent piston seizures. Provide appropriate lubrication to engine bearings.
Prevent fouling or preignition of spark plugs.
Burn cleanly without leaving deposits in the combustion chamber, exhaust port, or other parts of the exhaust system.
Leave little dirt on pistons. Keep varnish and deposits from forming and keep piston rings free.
Make little exhaust smoke and odor.
Possess anti-corrosion and anti-rust properties.
Mix easily with fuel.
Have good flow properties.
The two-cycle motorcycle engine disappeared from the American scene in the late 1970's due to governmental exhaust regulations. The demand for better air-cooled lubricants in turn slowed with this loss. This left the outboard motor as the primary American two-cycle engine.
Outboard growth was dramatic in the 1980's and with it went most lubricant research. But, the explosive demand for small lawn and garden two-cycle engines, and the resurgence of the snowmobile industry, in the mid to late 1980's, required a reassessment of lubricants for air-cooled two-cycle applications.
The frequency of carbon buildup often is determined by the quality of the local fuel supply, the particular characteristics of the engine and how the engine is used. Motors that run under heavy load are more prone to carbon deposits.
"Three of the four major outboard manufacturers (Suzuki is the exception) have acknowledged at least a few engine failures traced to carbon buildup in the past two years, a situation they blame on a combination of poor-quality gasoline and suspect outboard lubricants." ("Save Your Outboard's Life", Charles Plueddeman, Boating Magazine).
Unfortunately, it's all but impossible for a boat owner to detect carbon problems before engine failure is imminent. According to Yamaha, you may notice that your outboard becomes hard to start or spins unevenly while starting if the ring land becomes contaminated. Once the rings sticks in the ring land, however, it cannot hold a film of oil on the cylinder and scuffing will occur.Two-cycle formula selection must be based on maximum cylinder temperatures. Outboard two-cycle engines have very effective cooling systems, using low temperature lake or sea water, that keep ring belt temperatures between 100-275F. Organic ashless dispersant, based on nitrogen, provide engine protection to 300F. This additive technology also insures clean burning, which is of paramount importance in outboards due to their preignition sensitivity.
Water cooling reduces the cylinder wall temperature and makes piston seizure less likely than in air-cooled engines. This makes possible higher engine speeds. In an air-cooled unit, engine speed at maximum output ranges from 5,000 to 7,000 RPM. Water-cooling allows maximum engine speeds from 7,000 to 10,000 RPM. This trend toward faster speeds and higher output is expected to continue, with oil film formation an extremely important factor in wear control.
With the introduction of unleaded gasolines back in 1985, problems not apparent in the old days began to appear. In four-stroke automotive engines, valve recession, intake valve deposits, and injector nozzle clogging took place creating the need for new additives. In two-stroke outboards piston ring sticking and piston scuffing escalated. It has also been found that some of the commercial unleaded gasolines contributed more to carbon deposits than others. In its mild form, piston rings were cold stuck in the ring grooves. This caused hard starting and rough idle due to a loss in compression pressure. In its severe form, the rings were hot stuck in the ring grooves. This caused poor engine performance from the loss of combustion pressure and shortened engine life from piston scuffing.
Air-cooled engines such as: chain saws, weed cutters, snow blowers, leaf blowers, and most other pieces of air-cooled portable power equipment, are run in short bursts at varying speeds. In these applications, heat dissipates during periods of idle. Reduced engine life due to extremely high ring belt temperatures using water-cooled, low temperature, TC-W® type fluids; are often reported.
In addition, engine builders continue their never-ending quest to increase an engine's power density or specific power (output per cubic inch displacement.) During motorcross races, using the latest high-output technology in both motorcycle and snowmobile engines, race teams experienced reduced power output, especially toward the end of the race. After significant research, this loss of power has been generally attributed to increased cylinder temperatures, caused by greater power density output, and increased RPM's.
To reduce cylinder temperatures, a water jacket system was installed in these high-performance motorcycles and snowmobile engines. This allowed builders to increase RPM speeds by 30%. This increase in RPM's in-itself resulted in a significant increase of specific power output, while the water jacket keeps cylinders under critical temperature levels. This water jacket system soon found its way into the general marketplace, and spurred current sales promotions of high-output engines, especially in the snowmobile industry.
It must be noted that, although these water jacket systems may reduce engine cylinder temperatures under low operating conditions, they were specifically designed to control peak cylinder temperatures at these new higher output RPM's, and are usually found only in the highest output engines. In air-cooled two-cycle engines, cylinder temperatures average 300-350F. Normal exhaust port temperatures range from 1,200 to 1,600F. Some high output small engines have seen exhaust port temperatures measured as high as 2,000F. Ashless dispersant, typical of TC-W® type fluid formulas, are not thermally stable at these ring belt temperatures.
No matter what the marketing claims are, there is significant evidence that even the best TC-W3® formulas are marginal, at best, for extreme temperature/output air-cooled two-cycle engine applications. This conclusion is supported by the major two-cycle additive companies.
Industry studies indicate that the high temperatures encountered by air-cooled engines make them susceptible to premature failure when using oil designed for low temperature, water-cooled outboard engines. As a result of high temperature wear in air-cooled engines, increasing numbers of engine manufacturers are prohibiting the use of all TC-W® type oils. For example, Bombardier specifically prohibits the use of any NMMA TC-W, TC-WII OR TC-W3® outboard motor oils or other ashless 2 stroke-cycle oils in SEA-DOO® watercraft, Sea-Doo® JET BOATS and SKI-DOO® products. In addition, most chainsaw manufacturers worldwide specifically prohibit the use of TC-W® type outboard oils.
These manufacturers demand oils that contain a low-ash, natural metallic detergent, delivering much higher temperature engine cleanup and cylinder scuffing protection. Something that TC-W3® ashless oils cannot provide. Thermally stable, deposit wear control metal-organic compounds are needed for these extreme conditions. In addition, replacing bright stock base oils with a specially balanced combination of polyisobutylene dramatically increases piston scuffing protection as-well-as reducing carbon deposits and exhaust smoke. For more infomation regarding polyisobutylene in two-cycle oil see BP Chemicals PIB Applications.
But, this metallic component is simply not designed for use in water-cooled engines. The water-cooled engines in boats, are run at constant speeds for extended periods of time. As a result, the metal particles in a low-ash oil can heat to the "glow point" as the engine reaches extreme temperatures. The oil's fuel component could preignite and cause engine knock and piston burns. So, in most of these applications, ashless oil is the correct choice.
TWO-CYCLE GASOLINE ENGINE LUBRICANT CLASSIFICATIONS
Water-Cooled Outboard Engines
America has experienced a rapid change in two-cycle oils since 1960. The first ashless additives for outboards were introduced in the early 1960's. By 1970 the Boating Industry Association (BIA) defined the first technical requirements for an outboard motor oil, calling approved products TC-W®.
In 1980 lube injection was introduced for outboards and became widespread by 1984 necessitating a lubricant upgrade. In 1988 the National Marine Manufacturers Association (NMMA), formerly the BIA, issued TC-WII lubricant requirements. This change was a minor change from TC-W® requirements and was specifically aimed at the Variable Rate Oiling (VRO's) injector fluidity problems.
Testing criteria for TC-WII® did not account for numerous field problems reported using NMMA TC-WII® approved fluids. Although not all TC-WII® oils experienced trouble, a new TC-W3® specification was quickly established in April 1993, and included additional tests to eliminate these problems. This category insures greater protection against high temperature wear, gelling problems and the adverse affects of common, low grade "pipeline" gasoline. NMMA TC-W3® is now required for all outboard engines.
When a outboard oil has been tested and meets all of NMMA's requirements, a license is granted. The license permits the manufacturer to display the NMMA symbol on its product with the designation TC-W3®. The marketer's license, a six digit number starting with 3 or R, is also displayed on the container. An owner's manual will tell you to look for oils with the NMMA symbol. The warranty statement in the manual is the only warranty which is official and a mechanic or dealer has no authority to supersede this statement. Federal Law Prohibits dealers/mechanics to require the use of and OEM or specific brand of oil unless the dealer/mechanic can prove to the Federal Trade Commission (FTC) that, (1) no one else has an oil which will work, or (2) they must provide the oil to you free of charge for the required warranty period. See Magnuson-Moss Warranty Improvement Act.
Air-Cooled Land Based Engines
In 1988 the American Petroleum Institute (API) and the Society of Automotive Engineers (SAE) defined oil designations for different two-cycle engine oil applications. These included:
API TA - Asian Use, High Ash Oil
API TB - European Use, Medium Ash Oil
API TC - North American Use, Low Ash Air-Cooled Engine Oil
API TD - North American Use, Ash-Free Outboard, Water-Cooled Engine Oil.
Fluidity of the lubricant was defined by SAE under the following system:
SAE 1 - For high ambient temperature areas (African, Arabian, Asian tropics)
SAE 2 - For moderate to high ambient temperatures (southern US and Europe)
SAE 3 - For moderate to low ambient temperatures and water-cooled injector engines (northern US and Canada)
SAE 4 - Lowest ambient temperatures (Arctic conditions).
Unfortunately, for those who may have depended on this classification system to clarify two-cycle engine recommendations - it no longer exist. API canceled the system in 1993, deferring to the European ISO system and/or Japanese JASO system. Although there is no official two-cycle API classification, oil marketers continue to use the outdated test criteria establish for API TC to qualify air-cooled oils. They also use the SAE numbering system to define fluidity of their product.
These two new International designations for two-cycle engines have been adopted worldwide to classify high temperature air-cooled 2-cycle engine oils. From Europe the ISO "Global" system, and from Japan the JASO system.
ISO "Global" System
Global "GD" is internationally recognized as the highest quality air-cooled 2-cycle oil available. It is a synthetic or semi-synthetic, extreme temperature/anti-scuff/lubricity, low smoke, low ash oil. There is no comparable JASO or API product.
Global "GC" is equivalent to JASO "FC," Japan's highest quality 2-cycle oil. In Japan these oils may also be referred to as "Genuine" oils. These oils are high lubricity/detergent, low smoke, semi-synthetic, low ash oils.
Global "GB" Europe's lowest quality 2-cycle oil, is equivalent to JASO "FB." It is generally accepted that North America's API TC rated oils are equivalent to these oils. These oils do not require any synthetic to meet specifications, but do have detergent and/or lubricity additives, and are typically low to medium ash oils.
JASO System
JASO "FA" rated oils are used in Pacific Rim countries and are the lowest rated Japanese 2-cycle oils. They are medium to high ash mineral oils with limited lubricity or detergency.
JASO "FB" is equivalent to Global "GB." It is generally accepted that North America's API TC rated oils are equivalent to these oils. These oils do not require any synthetic to meet specifications, but do have detergent and/or lubricity additives, and are typically low to medium ash oils.
JASO "FC" is equivalent to Global "GC," Europe's medium quality 2-cycle oil. In Japan these oils may also be referred to as "Genuine" oils. These oils are high lubricity/detergent, low smoke, semi-synthetic, low ash oils.
SUMMARY
After all is said and done, the end use should always be the primary consideration when choosing a two-cycle engine lubricant. NMMA TC-W3 lubricants are a major improvement over their predecessors, both in water-cooled and air-cooled applications. The new Global and JASCO system defines quality and the service application of air-cooled oils worldwide, and should be making an impact on the North American market shortly.
Although TC-W3® approved oils do meet some high temperature performance requirements, current ashless technology will not meet the performance requirements of Global "GD," "GC," or JASO "FC" for high temperature wear and scuffing protection. Nor are they required to be low smoke oils, which is part of the Global and JASO specification. A premium quality "GD" or "GC" air-cooled oil is specifically design for high temperature/output air-cooled applications and will outperform TC-W3® outboard oils in most high output air-cooled two stroke-cycle applications.
[ October 20, 2002, 09:13 PM: Message edited by: BOBISTHEOILGUY ]
