What Does a Choke on a Lawnmower Do? And How to Use It.

Starting a lawn mower isn’t always easy. If your lawn mower hasn’t been started in a while or it’s cold outside, starting it up can be a challenge.

The choke on a lawn mower plays an important role in starting and getting the machine running. Using the choke correctly can actually make starting a mower much easier. So if you’ve ever wondered… ‘what does a lawn mower choke do?’… read on to learn more about this important part and how to use it.

What Does a Lawn Mower Choke Do?

A choke is very simple part of almost all carbureted gas engines. If you’re of a certain age or have spent much time around older cars, you know that even cars used to have a choke. A choke simply helps the user start a cold engine.

When the choke on a lawn mower is engaged, air flow is restricted to the carburetor — essentially “choking” the engine for air. This creates a higher fuel to air ratio, making it easier for the engine to start.

Once the engine gets going it needs more air to run. At this point, the choke will need to be released, allowing the engine to breath free.

How to Find the Choke on Your Lawn Mower

On many walk behind lawn mowers, the choke is actually built right into the throttle or speed control. The throttle lever likely has a symbol at one end of a line with a dot in the middle — this is the choke position.

Some lawn mowers may also have the choke located on the mower’s carburetor near the air filter. This type of choke is usually a switch that needs to be flipped.

Other mowers have no visible choke. The choke is automatic and will be applied by the mower as needed.

How to Use a Choke on a Lawn Mower

To use a choke, you’ll need to get your mower ready to use. Once you’ve checked to make sure your mower is full of fuel and ready to go, follow these simple steps to start your lawn mower with a choke:

  1. Park your mower on a smooth, level surface — like a driveway.
  2. Depress the lawn mower’s primer bulb several times, if it has one. This add some extra fuel to the carburetor and helps with starting.
  3. Engage the choke.
  4. Depress the bail lever — sometimes known as the “dead man’s lever.”
  5. Give the pull cord and good strong tug.
  6. When the lawn mower starts, switch off the choke and slowly increase the throttle if your mower is equipped with one.

What if I Leave the Choke On?

The choke is only used to start a lawn mower. Once the mower starts, the choke must be switched off or your mower will not run properly. Remember: the choke reduces air flow to the engine, but your mower needs more air to run at normal operating speeds.

If you leave the choke on too long, your lawn mower’s engine will “flood.” When an engine floods, it simply means that too much fuel and not enough air is in the carburetor. If your lawn mower floods and stalls, you’ll have to wait a few minutes for the carburetor to dry out before starting it again.

Your Turn

While a lawn mower choke might seem complicated, it’s actually a very simple part designed to make your life easier. You don’t have to be a mechanic to use one, but it does help to understand how a lawn mower choke works and why.

Next time you’re getting your lawn mower ready to mow, be sure to use the choke to get your yard work going quicker and easier.