Do all lawn mowers have a primer button?

Asked By: Slimane Naili | Last Updated: 11th February, 2020
Category: home and garden home appliances
4.4/5 (1,322 Views . 20 Votes)
While some machines have a choke plate, others have a primer bulb made out of rubber. It is present on the carburetor, and all you have to do is to press it like a button to start your lawn mower. It works by squirting fuel into your engine. The good news is that you don't have to panic or run to buy a new lawn mower.

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Considering this, where is the primer on my lawn mower?

Primer bulbs are usually positioned on the lawn mower one of two ways. They're either directly on the carburetor, or placed at a distance from the carburetor and connected to it with rubber tubing. Once you've gained access to the bulb's housing, remove the screws that hold it in place.

Secondly, can you run a chainsaw without a primer bulb? No, it won't work depending on the engine design. Without going into details the primer bulb forces fuel to the carb jets and not the engine directly. It also forces pressure and vacuum. Without the bulb your carb will be flooded on a permanent basis.

In this regard, how do you start a lawn mower with primer?

Starting a cold lawnmower is easier if you first prime the carburetor.

  1. Remove the cap from the lawnmower fuel tank.
  2. Locate the primer bulb on the side of the lawnmower engine.
  3. Press and release the primer bulb three times with your finger to prime the lawnmower carburetor.

What happens if you prime a lawn mower too much?

Over-Priming. Too many unsuccessful attempts to start an engine can cause flooding, because each attempt deposits more gas in the combustion chamber, and the mixture eventually becomes too rich. Over-priming floods the engine for a similar reason.

34 Related Question Answers Found

Is primer bulb necessary?

A primer bulb is important because it is helps to fill the carburetor with the correct amount of fuel. It does this by pulling fuel through the fuel line. You may need to fix or replace your primer bulb if: It is not creating proper suction.

How does a primer work on a small engine?

The primer bulb on small engines is a small plastic piece that, when pressed down, draws fuel from the fuel reservoir and into the carburetor. The carburetor is a part of the engine that mixes fuel and air together to make a combustion. Most weed trimmers have a primer bulb to prime the carburetor.

Why do primer bulbs stick?

Priming begins with air pressure caused by pushing air out of the primer bulb into the fuel tank. A clogged air filter or tight fuel tank cap that fails to vent properly can create a vacuum as the primer drives air into the fuel tank, failing to force the bulb back out.

Why do some primer bulbs have a hole?

the no hole primer is used when the primer is part of the carb itself. Yes the carb bowl vents through the primer hole on the engines with the primer mounted on the air cleaner. It is very common for the air cleaner backing plate, to warp were it mounts to the carb, and if it doesn't seal, when not prime.

How do you prime a craftsman platinum lawn mower?


How to Start a Craftsman Platinum
  1. Check the lawnmower engine oil before starting the engine to prevent damage to the internal rotating engine parts.
  2. Twist the gas cap from the fuel filler tube located on the fuel tank.
  3. Push the rubber primer bulb in on the side of the lawnmower engine carburetor five times by hand to start a cold engine.

How do you prime a Craftsman lawn mower?

How to Prime a Craftsman Push Mower
  1. Look for a flexible push-button style bulb on the carburetor of your Craftsman mower.
  2. Park the mower on flat, level ground.
  3. Press the primer bulb fully 3 times.
  4. Crank the engine.
  5. Repeat the priming and cranking process in colder weather if the engine fails to start the first time through the sequence.

How do you start a lawnmower without a primer?

How to Prime a Lawn Mower Without Primer Bulb?
  1. Find the air cleaner and remove its cover.
  2. Proceed to remove the air cleaner itself.
  3. The housing should be clearly exposed by now.
  4. Quickly put the air cleaner back in its original position and replace the cover.
  5. Now, your lawn mower is ready to use without the primer bulb!

How many times do you prime a lawn mower?

Engines with primer: For most temperature conditions, firmly push the primer bulb three times. In cooler weather, additional priming may be needed. A warm engine will usually not require priming. Every time you push the primer button, wait two seconds.

Can you put car gas in a lawn mower?

Can I pour leftover lawnmower gas in my car? No, the lawnmower wasn't a 2-cycle. I bought a battery electric mower to replace the gas mower. Even if the gas is two cycle, gone stale or both, just make sure you dump it in an almost full auto tank.

How do you start a Briggs and Stratton lawn mower?


How to Get My Briggs & Stratton Lawn Mower to Start
  1. Check the manual that came with your mower to determine the type of ignition system it has.
  2. Locate the priming bulb.
  3. Squeeze the handle lever to disengage the engine brake, if there is one.
  4. Start a mower equipped with the Ready Start Electric ignition system by turning the key to the Start position.

How do you prime a carburetor?

Simply cranking the car for 10 - 15 seconds should prime the carb.
  1. Crank the car for about 15 seconds.
  2. Stop for about 15 seconds.
  3. Pump the accelerator petal twice.
  4. Crank the car again, if it doesn't start immediately keep cranking the car for a maximum of 15 seconds.

How do you prime a Lawn Boy mower?

After you fill the gasoline and top off the oil, if needed, press the primer bulb in firmly and hold it in for a second before releasing it slowly. Press the primer bulb three times to start your lawn mower with a cold engine. If the air temperature is below 55 degrees Fahrenheit, press the bulb in five times.

What does a purge bulb do?

The purge bulb, used on many of today's two stroke outdoor power equipment engines, is designed to circulate fuel through the carburetor, removing air and allowing the carburetor to have a fresh fuel charge before attempting to start the equipment thereby aiding startup.

Can you bypass primer bulb?

Removing purge/primer bulb altogether. No, it won't work depending on the engine design. Without going into details the primer bulb forces fuel to the carb jets and not the engine directly. Without the bulb your carb will be flooded on a permanent basis.

Why does my primer bulb not work?


When the primer bulb isn't working, it may be a problem with the bulb itself, with the fuel lines that feed fuel to the bulb or both. The same goes for fuel lines. When they've hardened and cracked, they let in air, which makes it impossible to draw the fuel into the carburetor properly.

How do you install a primer bulb?

Reviewing these steps will likely help with primer bulb replacements on other engines.
  1. Access the carburetor.
  2. Unscrew the two carburetor mount screws.
  3. Remove the old primer bulb.
  4. Clean the carburetor and primer bulb components.
  5. Install the new primer bulb.
  6. Remount the carburetor.