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How to Tell If My Lawnmower Is a 2 Cycle?

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It's crucial that you know whether your lawn mower has a 2-cycle or a 4-cycle engine. For example, each type of engine requires different fueling techniques. If you try to fuel a 2-cycle engine as you would a 4-cycle engine, it will freeze up. The engine will then likely need to be replaced. Likewise with a 4-cycle engine. Fuel it up improperly and and can foul-up, or even damage, the carburetor.

Determine how to add fuel to your lawnmower. Both types of mowers will have gas tanks, of course, but look for a crankcase with a filler tube to add oil. The top will screw off to reveal a dipstick. If there is a place to add oil separately, it's a 4-cycle engine. If you mix oil along with the gasoline when you fuel up, then that tells you it's a 2-cycle lawnmower.

  • It's crucial that you know whether your lawn mower has a 2-cycle or a 4-cycle engine.

Refer to the maintenance section of the owner's manual. If it instructs you to change the oil on a regular basis, as well as before you store it for the winter, then you have a 4-cycle lawnmower.

Try to start the lawnmower during the cold weather. Two-cycle engines start much easier. However, they give off more smoke. Also pay attention to the noise the lawnmower makes when it's running. A machine with a 2-cycle engine is much noisier than a machine with a 4-cycle engine.

  • Refer to the maintenance section of the owner's manual.
  • If it instructs you to change the oil on a regular basis, as well as before you store it for the winter, then you have a 4-cycle lawnmower.

Run the lawnmower up a steep incline. A 2-cycle engine won't lose its power like a 4-cycle engine will. It will have approximately twice as much power.

Lawnmower Revs Up & Down

Whether your lawnmower is a shiny new model that's your pride and joy, or an old faithful model that you've had for years, you want it to work correctly when it's time to mow the lawn. A mower with an engine that revs erratically, also known as hunting and surging, indicates that you need to address a problem. Check the vented gas cap as well. Check the spark plug to see if the wire is connected to it firmly and not wobbling about. If necessary, replace the spark plug with a new one. One screw controls the idle speed while the other adjusts the idle mixture. Then slowly adjust the screws tighter or looser in turn until the mower runs and idles smoothly. If you have gas-powered blowers and trimmers that use a mixture of 2-cycle oil and gasoline, check to see that you've not placed that mixture in the lawnmower inadvertently.

  • Run the lawnmower up a steep incline.
  • If you have gas-powered blowers and trimmers that use a mixture of 2-cycle oil and gasoline, check to see that you've not placed that mixture in the lawnmower inadvertently.

Tip

Because 2-cycle engines are smaller and lighter, they are best for small machines like leaf blowers and chainsaws. Keep that in mind when you're making the comparisons.

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