There are several possible reasons why your lawnmower won’t start, and one of them is a broken primer. The primer allows clean fuel into the carburetor. Which then sends it to the engine to power on the mower. Read this if you’re trying to figure out how to prime a lawnmower without a primer.
The carburetor works with the primer to send fuel to the engine and create a spark that powers it on. So without the primer, there’ll be no spark therefore, the engine will not start.
It is essential to know how to turn on your mower without the primer since it can go bad after a while. We will explain how to turn on your lawnmower if your primer is faulty in this guide.
What is a primer bulb?
The primer bulb is a small red bulb or button located near the carburetor. Its function is to push fresh fuel and air mix to the carburetor. The carburetor goes dry from time to time and needs the primer to send fuel to it. It then sends it to the engine, thereby creating a spark that starts the machine.
There are two types of primers, and they both perform the same function. One is the primer bulb, and the other is the automatic primer. The bulb is located on the outside, near the carburetor. But the automatic type works from the inside, sending fuel to the carburetor to power the engine.
Why does a mower primer stop working?
Several reasons can cause a primer to fail to work. But these three are the most common:
- Cold primer
- Broken bulb
- Dirty fuel filter
Pulling your mower out of the garage after a long time could mean the primer has been without use for too long. It can fail to work since it is probably dry now; no drop of fuel on it. No matter how much you try, the mower will not start because fuel is not reaching the combustion chamber to start the engine.
If you have the primer bulb on your mower, check If the rubber is torn or has any holes. If it is, the mower can not start since the bulb is unable to push fuel into the carburetor in that condition.
If dirt clogs the fuel filter, the primer can not work since that is where it takes the fuel from. It is not able to send the combustible to the carburetor, and the mower will not start as a result.
You can bypass the primer and start the mower no matter what the fault of the primer is.
We will show you how. But before that, consider these points before you prime the mower:
- It might take you up to 20 minutes to complete this priming process, much less time if you’re technically inclined and have experience with lawnmowers.
- You may need starter fluid to finish the priming. Starter fluids are liquid flammable substances used when a piece of equipment, such as a mower, would not start and needs priming.
- The starter fluid is thicker than fuel. You should only sprinkle a little quantity to prevent clogging and blocking the air into the carburetor.
Follow the steps below to prime your lawnmower without a primer.
It is quite a straightforward process to prime the mower without a primer. You don’t need any fancy tools to do it.
The process won’t take long, and you would get your mower started for the day’s work before you know it. Let’s begin.
What you’ll need to have:
- Starting fluid (to wet the carburetor)
- Flat head screwdriver
What you’ll need to do:
- Prep the mower
- Check the fuel content – make sure there’s enough to power the machine. Add fuel if it is low.
- Remove the cover at the top of the mower – check everything, including the carburetor, the filter, and the fuel pipes. Make sure they are all in good condition
- Identify and Inspect the primer
- Push the throttle down
- Find the air filter and remove it
- Sprinkle the starter fluid
- Return the air filter and start the engine
First, you need to ensure the mower is in working condition to start. Prepare the mower for priming by doing the following:
Confirm that the fuel pipes are still in place and there’s no disconnection. If there is, the mower will fail to start.
If yours is the primer bulb, it should be beside or under the carburetor, near the engine. It is a black or red button-like device, though it looks like a small bulb.
Check if it is broken or torn. If so, you can’t start the mower without it. If it is not torn, and there are no holes in it, push the button three times to pump some fuel into the carburetor.
After that, try starting the engine again.
If the engine does not start after you push the primer bulb, and if the bulb is in good shape, pull the throttle lever to its higher position.
Then drag the starter rope. The engine may attempt to power on at this point.
Push the throttle all the way down and pull the starter rope again. This should start the engine.
If not, go to the next step.
You should find the air filter near the side of the engine. There will be a plastic or metal cover housing it. Gently unscrew its cover to reveal the filter.
Take a mental note of where each screw or bolt goes and how the filter sits inside the compartment. This way, you would have no problem fixing it back in its place.
Once you have unscrewed or unbolted the cover, carefully take out the filter.
The air filter is usually situated in the place where air passes to the carburetor. This is where the fluid can be sprayed to get the machine to start. Once you take out the filter, sprinkle very little fluid in this area. It goes straight into the carburetor. Which then sends it to the engine.
If the filter is dirty, you might want to wash or clean it before putting it back, depending on the type. But ensure you cover the area quick enough so that the fluid does not evaporate.
After putting it back correctly, start the mower like usually do. It should take more than a couple of tries before it starts. But it refuses to start, sprinkle more fluid on the air filter area and try again.
Once it starts, you know the process is successful.
Why do lawnmowers have Primer bulb?
Lawnmowers come with small components, such as small engines, carburetors, etc. They are not as big as regular vehicle, so the size of these parts should be according to the equipment.
The carburetor is responsible for mixing the fuel with the right amount of air and passing it to the combustion chamber. Which then ignites the engine and powers on the mower.
The small carburetor holds a small amount of fuel to make the process successful. If you don’t turn on the mower for sometime, the fuel dries off. To turn on the mower engine, the carburetor needs fuel. This is the work of the primer bulb. It pumps the fuel to the carburetor. Without that, the engine will not start.
Therefore, if the primer suddenly fails or breaks, you need to find a different way to pump fuel into the carburetor. We explained this procedure above. But this is a temporary fix for when you need to use the mower immediately. You should consider replacing the primer as a permanent solution.
As you have seen, priming your mower without a primer is not a difficult thing to do. You only need to push the primer button, and if that doesn’t work, sprinkle starter fluid near the air filter. This should get your mower to start.
However, this is a temporary measure when you suddenly discover the problem and can’t wait to mow your lawn. You should replace it soon enough if it has broken.
If, after following the steps above, the mower still does not start, contact a professional to have a look at the mower.