If you have just bought a snow blower, then you might be wondering if the engine runs on regular gasoline or a mixture of gas and oil.
Whether your snow blower requires gasoline or a gas and oil mixture depends on the type of engine. For instance, you pour a mixture of fuel and oil into the gas tank of a two-stroke (2-cycle) engine. This provides fuel for internal combustion and a small amount of oil for lubrication. In contrast, a four-stroke (4-cycle) engine has separate tanks for gasoline and oil. The quickest way to recognize the difference between these two engine types is to look for an oil dipstick sticking out of a crankcase. If an oil dipstick is present, then it is a four-cycle engine.
Do most snow blowers have 4-cycle engines?
At the present time, probably all the newer snow blowers have 4-cycle engines, owing to the better fuel efficiency and cleaner exhaust fumes of four-stroke engines. Two-stroke engines are not considered to be environmentally friendly because of their dirty exhaust emissions. Therefore, you might only find a two-stroke engine on a snow blower if it is already ten or twenty years old.
What is the difference between 2-cycle and 4-cycle engines?
There are mainly two types of gasoline combustion engines: the 2-stroke and the 4-stroke.
Foremost, the stroke refers to the movement of the piston inside the cylinder from the top to the bottom. The full combustion cycle requires the following events to occur.
First, the air and fuel mixture is sucked through the opened intake valve into the combustion chamber as the piston moves down to the bottom.
Second, the intake valve closes while the piston moves up to the top of the cylinder, compressing the air and fuel mixture.
Third, the spark plug produces a spark, the gas ignites, it rapidly expands, forcing the piston downwards in a powered stroke.
Fourth, the exhaust valve opens up while the piston moves upwards again, pushing the exhaust gases out of the combustion chamber.
As discussed, the major strokes in a combustion cycle are the intake, compression, combustion and exhaust strokes.
In a 4-stroke engine, the four strokes happen as described above. However, in a 2-stroke engine, the combustion cycle is completed in only two strokes. That is, the combustion and exhaust strokes happen at the same time, while the intake and compression are combined. Please note that a two-cycle engine does not have valves. Instead, it has intake and exhaust ports that are closed and revealed by the movement of the piston.
I think I got that right, but you can watch this video, just in case I got it wrong. A video might be worth a thousand words…
Is a 4-stroke engine better than a 2-stroke?
A four-stroke engine has a few benefits that make it more acceptable when compared to a two-stroke engine. For example, a 4-cycle engine burns fuel very efficiently, while the 2-cycle engine tends to be much more inefficient, belching out unburned gas and oily exhaust smoke. Furthermore, a 4-cycle engine is quieter when compared to the high-pitched noise of a 2-cycle engine.
Comparatively, a two-stroke engine has better torque at higher RPM, and are generally more powerful. However, being able to run at higher RPM also creates more wear and tear on the engine, as well as more noise. Of course, you do not have to worry about checking the oil, seeing as the oil is mixed with the gasoline to provide lubrication. Although, a 2-cycle engine that has an oil injection system will need an oil check now and then. Two-stroke engines have less moving parts, while the extra components of a four-stroke engine makes it both heavier and more complex to maintain.
Overall, 2-stroke engines are dirtier than 4-stroke engines: for that reason, most snow blowers will be powered by a 4-cycle engine. Although, you might still find an old model snow blower that has a two-cycle engine on it.
What is the oil and gas mixture ratio for snow blowers?
It is important to know that each 2-cycle engine type is made to work with a specific gas to oil ratio. You have to check the snow blower’s manual for that information. Keep in mind that you should not use regular engine oil, but only use oil that is made for 2-cycle engines.
Generally, the two-stroke engine on a snow blower requires a gas to oil mixture in a ratio of 50:1. Putting it differently, you mix fifty parts unleaded gasoline with one part certified 2-stroke oil. The unleaded gasoline should probably have a minimum octane rating of at least 87, and the ethanol content should not exceed 10%.
There are two basic steps to making a gas and oil mixture. The first step is to measure and pour the precise amount of oil into an empty gasoline can that you will only use for mixing 2-cycle fuel mixtures. The second step is to slowly fill up the gas can with the exact amount of gasoline required. You should never rely on mixing the oil and gas inside the fuel tank of a snow blower. Also, try to use the fuel mixture within a month, so that it does not get stale.
What is the best gasoline for a snow blower?
The best gas to use for a snow blower engine does not contain any ethanol. Ethanol-free gas does not absorb so much moisture from the air, which will greatly reduce the amount of corrosion in the fuel system. Gasoline that does not contain ethanol (E0) should still be available in most parts of the country.
If you do not use ethanol-free gasoline, then you may use unleaded gasoline that contains no more than 10% ethanol by volume (E10). The gasoline should have an octane rating of 87 or higher. The octane rating must not be lower than 87, nor should the ethanol level be higher than 10%.
Never fill up your snow blower’s gas tank with E15, E20, or E85 fuel. This might cause the engine to perform poorly, or damage the engine, and lead to increased corrosion of the components in the fuel system. To explain, the ethanol fuel absorbs more water from the air when compared to ethanol-free gas, given that both the fuel tank and the carburetor are vented to the outside air. The water absorption effect of ethanol can be reduced by using fresh fuel that are not more than three or four weeks old.
Besides, you can keep gasoline fresh for longer by adding a fuel stabilizer to the fuel on the day of purchase. The fuel stabilizer forms a protective layer on top of the gasoline. This reduces both the absorption of moisture from the air, and the evaporation of the fuel’s volatile compounds. This treatment will help to protect the fuel system against corrosion. Moreover, it prevents the formation of sticky brown deposits due to the evaporation of volatile compounds from the fuel. For the most part, you should avoid storing a snow blower with gasoline in its tank for long periods of time.
Photo by Chris Haws on Unsplash