Motor Oil Info

AMSOIL products are tested to ensure they not only meet, but surpass the demands of the engine and operating environment for which they are developed. We recognize the importance of performance and reliability, which is why we engineer our two stroke oil with high quality chemistries to exceed industry standards and address specific demands of various two stroke applications.

In general, AMSOIL Dominator is ideal for two stroke racing applications; AMSOIL Interceptor is ideal for two stroke recreational equipment; hp injector and Saber outboard are ideal for two stroke marine equipment; and Saber Professional is ideal for lawn and garden power equipment.

Of the current two stroke specifications, NMMA TC-W3 is probably the most well known. It was developed by marine engine manufacturers for water cooled outboard engines; however, it has been deemed appropriate for other two stroke engines by many manufacturers of land based two stroke engines.

API TC is a long standing specification that applies  to air cooled engines, which may include those with a radiator. JASO and ISO two stroke specifications apply to air cooled engines commonly found on handheld power equipment.

Other area of importance for two cycle engines, Exhaust port deposit control to keep exhaust valves functioning, fluidity for oil injection systems, miscibility for mixing oil with gasoline at cold temperatures and rust protection for storage. Specifications are in place to help consumers choose the right oil for their applications.

Two stroke specifications are developed and managed by multiple governing bodies, including the Japanese Automobile Standards Organization (JASO), the International Standards Organization (ISO) and the National Marine Manufacturers Association (API) also has a specification for two stroke engine oils. Most of these organizations have adopted standards focused on lubricity, detergency and prevention of pre ignition.

Prevention of pre ignition in the combustion chamber is important for efficient two stroke operation. If the by products of burned fuel and oil accumulate inside the combustion chamber, deposits can build on top of the piston (the crown). Piston crown deposits can absorb heat from the burning fuel and oil, creating hot spots that can ignite the fuel/oil mixture before the spark plug fires, which is known as pre ignition.

Pre ignition can cause the temperatures and pressures in the combustion chamber to rise beyond the failure limits of the piston and head gasket, resulting in catastrophic engine damage. Ultimately, prevention of pre ignition requires a lubricant carefully formulated with the proper detergent additives in the right amounts for effective deposit control.

Lubricity describes an oil’s friction reduction properties. Lubricity is critical for managing the excess heat and high operating rpm common in two stroke engines. High heat is generated not only from the rapid combustion process, but also from piston to cylinder friction. Two stroke applications require a lubricant that withstands the HEAT! If the oil burns off too easily from combustion or does not provide the needed lubricity for piston lubrication, piston scuffing will occur, causing lost performance and even engine failure.

Detergency describes a lubricant’s ability to control engine deposits. In two stroke engines, deposit control is especially important on the piston skirt and ring areas in order to prevent ring jacking and ring sticking. Ring jacking occurs when deposits accumulate behind the piston rings and force them against the cylinder wall, rupturing the lubricant film. Ring sticking is caused by deposit formation on the top and bottom of the ring within the ring groove that prevents the ring from forming a proper seal in the cylinder. If a proper seal is not formed, gases and heat from the combustion process can escape past the piston and burn the protective lubricant off the cylinder wall.

Two stroke engines are lubricated by oil that is consumed during the combustion process. In addition, combustion occurs on every revolution of the crankshaft in a two stroke application, compared to every other revolution in a four stroke engine, which generates more heat and places greater demand on the lubricant.

The oil burned in the two stroke combustion process can leave deposits on the piston crown, skirts and ring grooves. Two stroke oil must be formulated to burn as cleanly as possible and control deposit formation; excessive deposits can result in engine failure. The high heat and tendency for deposit formation in two stroke engines necessitate an oil with excellent lubricity, detergency and ability to prevent pre-ignition.

It is important to remember that normal use of chainsaws by a commerical logging outfit easily qualifies as extreme severe service. At the end of the 200 hour test period, the saws were returned with missing paint, cracked handles and an overall appearance of abuse.

After the test period the saws were subjected to a detailed engine teardown to determine how well Saber performed. As expected, the teardown revealed that the chainsaws using AMSOIL Saber Professional at a mix ratio of 100:1 had fewer deposits, LESS WEAR and were generally cleaner inside than the saws that operated using the manufacturer recommended two cycle oil mixed at 50:1. In addition, the chainsaws with Saber installed used an average of 8% less fuel than the saws running conventional oil at 50:1.

AMSOIL Synthetic 100:1 2-Cycle Oils have been providing improved performance and protection in 2-cycle motors since 1973. However, there are still consumers who struggle with the notion that Saber provides optimum protection at 100:1 when the equipment manufacturer has specified a 50:1 ratio.

In order to once again demonstrate the superiority of AMSOIL Synthetic 2-Cycle Oils, AMSOIL provided a logging company with six Stihl MS440 chainsaws. Three of the saws were operated using the manufacturer recommended mix ratio (50:1). The other three saws had AMSOIL Saber Professional installed at a mix ratio of 100:1. The loggers used all six saws as they normally would for 200 hours. Results to come.

AMSOIL Saber Professional Pre-Mix 2 Cycle Oil is formulated with exclusive AMSOIL Synthetic Base Oils and Premium Additives. Designed for lean mix ratios in two cycle motors, Saber Professional has excellent lubricity and cleanliness properties to control friction and help prevent wear, plug fouling and ring sticking.

Saber Professional has a recommended MIX RATIO OF 100:1, even when the application calls for a ratio of 50:1. Its high quality base oils resist consumption and evaporation better than conventional two-cycle oils. The combination of premium base oil chemistry and superior additive technology allows Saber Professional to deliver maximum performance and protection in small engine applications: even at 100:1. OUTSTANDING!!!!

Two-stroke motors have what are considered total-loss lubricating systems. Because the crankcase is part of the intake process, it cannot act as an oil sump like on four-stroke engines. Lubricating traditional two-stroke engines is achieved by mixing the oil with the fuel. The oil is burned upon combustion of the air/fuel mixture.

Direct injection engines are different because the fuel is directly injected into the combustion chamber while the oil is injected directly into the crankcase. This process is efficient because the fuel is injected after the exhaust port closes, and therefore more complete combustion of fuel occurs and more power is developed. Direct injection engines have a higher power density than traditional two-stroke engines. Because the oil is direct injected into the crankcase, less oil is necessary and lower oil consumption results. They also require more lubricity than traditional two-stroke engines.