Do Chainsaws Take Mixed Gas?

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Yes. All chainsaws require premixed gas to run at the optimum temperatures. The oil you add to gas will lubricate the piston and crankshaft and keep the engine cool for smooth running.

Since the piston moves up and down at high speed, enormous friction heats it.

So, if there is no oil to keep the fuel burning at high temperatures, the piston and the metal on the cylinder will heat and expand to a point where the piston can no longer move smoothly up and down inside the cylinder.

This will increase the friction inside the cylinder, causing the piston to stop moving completely. The crankshaft will also stop moving, and the system will shut down instantly.

How to Mix the Oil

The recommended ratio for most two-stroke chain saw combustion engines is 50:1, but some manufacturers recommend a ratio of 40:1.

The larger number is the gasoline amount, while the smaller is the amount of oil you should add. You should mix your fuel in a container designed for fuel before filling it in your chain saw.

You should also use the premixed fuel within a few days and always shake it well if it has been sitting for a while to mix the oil completely with the gas.

How to Mix Chainsaw Fuel

Step1: Select the Best Oil type for Your Application

The first thing to do is ensure that the oil type you’ve chosen is the right one for your engine. The two oil types for 2 – stroke chainsaw engines are low smoke and high-performance oils.

  • High-performance (HP): High-performance oils are best for small and water-cooled engines.
  • Low Smoke (LS): These oils promote durability of engine parts by keeping its temperature at an optimum range. In addition, they can significantly lower smoke emissions.

Depending on your priorities, you can choose any of the above oil types: if you are looking for performance, HP oils will be the best choice.

On the other hand, LS oil will serve you better if you want lower emissions. It is also important to consider the viscosity of the oils.

People in warm areas should always choose thicker oils like 10W30 and 10W40. On the other hand, people living in colder areas should go for thinner oils, like 5W30 lubricants, for better cold starting.

Step 2: Select the Right Fuel Type for Your Chainsaw

After selecting the best oil type, you should choose the right fuel type. The two most common forms of fuel are standard unleaded and ethanol-blended (E10).

Though both fuels work in all chainsaw (7 common problems with Husqvarna Chainsaws) engines, unleaded fuel may be better because it enhances performance and enhances the durability of components.

You may be required to service the fuel lines and carburettor more often if you use fuels blended with ethanol. The fuel should also have an octane number of more than 89 for smooth combustion.

Step 3: Use a Clean Fuel Container

The container you use to store the mix should be clean. Using dirty oil containers will contaminate the fuel because they contain dirt and debris.

These deposits will accumulate and eventually jam your chainsaw’s carburettor jets, making it difficult to start the engine.

Step 4: Mix the Fuel with Oil

After getting the right fuel and oil type for your chainsaw, prepare the mix in the right ratios. As said earlier, your ratio should be either 50:1 or 40:1. Don’t store the fuel-oil mixture for more than 30 days.

Step 5: Add the Mixed Fuel into the Engine

After preparing the fuel-oil mix in a clean can, you can insert it into your engine. You can use a funnel to pour the oil directly into the oil cap to avoid spills.

You can then store the container with the mix in a suitable place. Remember to add a stabiliser if you intend to keep it sitting for more than 30 days. A fuel stabiliser prevents the fuel quality from degrading.

What Should I do If I Accidentally add Raw Fuel into the Tank?

If you forget to mix the oil with fuel before adding it into the tank of your chainsaw, avoid starting the chainsaw and drain the fuel from the tank.

It is also advisable to add one tablespoon of water into the tank, shake it a bit and pour it out. You should also clean the carburettor and change the fuel lines.

Raw gas will also not damage the chainsaw’s engine if it runs for less than 5 minutes. So, if you have realised that the fuel is not mixed after running your chainsaw for a few minutes, turn off the engine and pour it out.