Two-stroke oil
Encyclopedia
Two-stroke oil is an engine oil intended for use in two-stroke engines.
Unlike four-cycle engines which have a closed crankcase, these lightweight engines use the crankcase as part of the induction
tract, and therefore, oil must be mixed with petrol to be distributed throughout the engine for lubrication
. The two-stroke oil is ultimately burned along with the fuel resulting in exhaust emissions with blue smoke and/or a distinctive odor.
The oil-base stock is either petroleum
, vegetable
, semi-synthetic or synthetic oil
and is mixed with petrol/gasoline at a fuel-to-oil ratio ranging from 16:1 to as low as 100:1.
Engine original equipment manufacturer
s (OEMs) introduced pre-injection systems (sometimes known as "auto-lube") to engines to operate from a 32:1 to 100:1 ratio. Oils must meet or exceed the following typical specifications: TC-W3TM, NMMA, [API] TC, JASO FC
, ISO-L-EGO.
Comparing regular lubricating oil with two-stroke oil, the relevant difference is that two-stroke oil must have a much lower ash content. This is required to minimize deposits that tend to form if ash is present in the oil which is burned in the engine's combustion chamber.
Unlike four-cycle engines which have a closed crankcase, these lightweight engines use the crankcase as part of the induction
Forced induction
Forced induction is the process of compressing air on the intake of an internal combustion engine . A forced induction engine uses a gas compressor to increase the pressure, temperature and density of the air...
tract, and therefore, oil must be mixed with petrol to be distributed throughout the engine for lubrication
Lubrication
Lubrication is the process, or technique employed to reduce wear of one or both surfaces in close proximity, and moving relative to each another, by interposing a substance called lubricant between the surfaces to carry or to help carry the load between the opposing surfaces. The interposed...
. The two-stroke oil is ultimately burned along with the fuel resulting in exhaust emissions with blue smoke and/or a distinctive odor.
The oil-base stock is either petroleum
Petroleum
Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...
, vegetable
Castor oil
Castor oil is a vegetable oil obtained from the castor bean . Castor oil is a colorless to very pale yellow liquid with mild or no odor or taste. Its boiling point is and its density is 961 kg/m3...
, semi-synthetic or synthetic oil
Synthetic oil
Synthetic oil is a lubricant consisting of chemical compounds that are artificially made . Synthetic lubricants can be manufactured using chemically modified petroleum components rather than whole crude oil, but can also be synthesized from other raw materials...
and is mixed with petrol/gasoline at a fuel-to-oil ratio ranging from 16:1 to as low as 100:1.
Engine original equipment manufacturer
Original Equipment Manufacturer
An original equipment manufacturer, or OEM, manufactures products or components that are purchased by a company and retailed under that purchasing company's brand name. OEM refers to the company that originally manufactured the product. When referring to automotive parts, OEM designates a...
s (OEMs) introduced pre-injection systems (sometimes known as "auto-lube") to engines to operate from a 32:1 to 100:1 ratio. Oils must meet or exceed the following typical specifications: TC-W3TM, NMMA, [API] TC, JASO FC
JASO FC
JASO FC is a performance quality classification for two stroke engine oil, for engines of Japanese origin.Oils are granted the JASO FC certification by the Japanese Automotive Standards Organization, under the test sequence M345. JASO FC is the highest rating for 2-stroke oils. JASO FC oils leave...
, ISO-L-EGO.
Comparing regular lubricating oil with two-stroke oil, the relevant difference is that two-stroke oil must have a much lower ash content. This is required to minimize deposits that tend to form if ash is present in the oil which is burned in the engine's combustion chamber.