Honda Spree and Elite 50 Forums

One difference is Injector oil's got to flow easily at low temperatures. Most important is the oil pump passages. The Honda pump I took apart used a compression spring as part of the pump operation. My opinion is if the oil is too thick the pump return stroke will not be full travel. Clearly higher RPM's would the worst for 'pump float'. Bad just when you need it

Compare some GN2 with pre-mix or castor in the cold.

Using injector oil as pre-mix can be confusion - premix usually has dye, but GN2 in the weedeater fuel can = Good thing the 4 cycle gas is in a different size can.

I found this on 2 stroke oils.

http://www.ultralighthomepage.com/OIL/oil.html

I learned that part of the TCW testing requires an air cooled segment, so it will work in air cooled engines. However, water cooled oil and air cooled oil are formulated totally differently.

"The chart in Table 1 shows the general operating conditions of each type of engine."



"To understand how two-cycle oils work in your engine, we need to cover some basic training on engine operating conditions and oil formulation. Outboard engines are characterized by their constant speed, high output operation. They are usually set at a desired high speed and continue at that speed until the destination is reached and then throttled down. Also, they are constantly cooled with fresh, cool, non recirculated water. Chain saws, on the other hand, are a high action operation. They are constantly started and stopped, used for short periods, and frequent overloads are its hard place in life. Additionally, they have smaller displacements than outboards and are air cooled. By understanding how the operation of an engine can affect the oil used and how an oil can affect the engine, we can better appreciate the difference between a water cooled two-cycle oil and one formulated for an air cooled two-cycle engine. The components used in these two oils, and reasons for their use are shown in Table 2."