Technical Specifications

2-Cycle Engine 40:1 and 50:1 Mixture Ratio

Information

Unlike four-cycle engines that have a separate oil reservoir for lubricating the engine, two-cycle

engines are lubricated through the combustion cylinder by mixing specially formulated oils with

the fuel. Running a 2-cycle engine with the wrong gas/oil mixture will seriously damage your

equipment, and running one without any oil in the fuel will completely destroy your pump’s

engine in seconds.

How Long Does Gasoline Keep?

Using "new" gasoline in a gas-powered engine is not necessarily the same as using “fresh”

gasoline. The gas that just came out of the gas-can might be “new” to the engine but if it has

been stored for three to six months it might not be “fresh”. Old gasoline will break down and

lose its full potency and will reduce the power output of your pump’s engine and can cause

excessive impurity build-up in the engine’s parts.

Tips for proper gasoline storage and use:

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Discard gasoline after storing it for three to six months.

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If you store your gas-powered pump with fuel inside the gas tank, use a fuel stabilizer to

protect the engine’s carburetor.

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Even if you use a fuel stabilizer when you store your engine, discard the gasoline at the start of

the next season. The stabilizer is only there to keep the carburetor from drying up.

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If you're determined to store gasoline for long periods of time, use a fuel stabilizer. Fuel

stabilizer can extend the life of stored gasoline up to several more months.

Oil/Gas 40:1 Mixture Ratio – Oil/Gas 50:1 Mixture Ratio

Every 2-cycle engine has a specific gas/oil mixture ratio. This gas/oil ratio is displayed on side

of the engine’s gas tank, on the gas cap, and/or in the owner’s manual. For a 40:1 mixture, there

are 128 ounces in one gallon, so divide the 128 by 40 and that will give you the number of

ounces of 2-cycle oil you need for one gallon of gasoline. You will need 3.2 ounces of oil for

every gallon of gasoline for a 40:1 mixture ratio. For 50:1 you will need 2.6 ounces for

every gallon of oil.

2-Cycle Engine Oil Mixing Steps

1. The oil should always be added first.

2. Pour the pre-measured amount of 2-cycle engine oil into a clean gasoline container.

3. Add 1 gallon of gasoline to the oil.

4. Seal the gas container and gently swish it until the oil completely mixes. Do not shake the gas

container.

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2-Cycle Engine 40:1 and 50:1 Mixture Ratio Information Unlike four-cycle engines that have a separate oil reservoir for lubricating the engine, two-cycle engines are lubricated through the combustion cylinder by mixing specially formulated oils with the fuel. Running a 2-cycle engine with the wrong gas/oil mixture will seriously damage your equipment, and running one without any oil in the fuel will completely destroy your pump’s engine in seconds.
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Mixing too much oil in your 2-cycle engine is much less damaging to the engine than mixing too little oil. If there's only a little too much oil in the mixture, you may not notice any difference in your engine's performance at all. The important thing is that it's being lubricated. Smoky exhaust, oil out the muffler and loss of engine power are some of the symptoms that might appear if a lot of extra oil is mixed in the fuel.