How To Bypass Primer Bulb On Weedeater In 2021?

A broken primer bulb of your weedeater might not be the best thing for you. Especially when you have piles and piles of leaves stocked up in your backyard. And the weedeater is the most essential thing for you at that time. You know pretty well that the weedeater is quite useless without that primer bulb on it. Bypassing the primer bulb will turn your weedeater on instantly. So, how to bypass primer bulb on weedeater?

First, you need to remove the screws and get rid of the faulty air bulb. Then, pull the metal plate away and clean the air bulb seat. Put a polythene as a replacement of the air bulb and screw it into place with the metal plate. Lastly, press the little ball of polythene till the bubbles in the carburetor line appear.

how to bypass primer bulb on weedeater

Sound worthwhile of your time today for the sake of your weedeater? If so, let’s start off with the essential you need to grab first-

Grab These Essentials

The most essential things that you’re going to need to bypass the primer bulb might be right next to you.

However, you need to double-check that the things that you’re getting are good enough to get your work done right at the moment.

Or else, you’ll turn up messing the whole weedeater up rather than bypassing the primer bulb.

Here’re the things you’ll need-


You’ll need to unscrew the screws that hold the metal piece of the primer bulb in places.

Polythene (Highly Durable and Flexible)

By putting polythene under the metal plate, we’ll create it as a ball-like structure. 

Now, we know what you’re thinking, just two? Yes, these two things are enough to get your job done for now. At least it’ll turn on the weedeater for now.

6 Steps On How To Bypass Primer Bulb On Weedeater

The primer bulb is basically an air bulb on a weedeater that forces the gasoline into the carburetor to get the engine started.

You see, each push of the bulb sprays a fine mist of gasoline along with the air needed for the weedeater to start.

As the air bulbs are made of plastic or rubber most of the time, it eventually cracks or breaks after long term usage.

To repair this you just need another bulb and replace it. But you might face a situation when there’s no bulb available near you and you need the weedeater turned on right away.

However, the repair we’re going to show you is just going to take a few minutes only to get the weedeater started.

So, let’s check out how you’re going to bypass primer bulb step-by-step-

Step 1: Remove the Screws

You’ll notice that there are two screws on each side of the air bulb. You need to remove those two screws from the metal plate using a screwdriver.

However, you might also find flat -head screws or Philips head screws. It basically depends on the brand of your weed eater.

After you’re done removing the screw, keep them aside to a certain place so that you don’t lose it.

Step 2: Pull Away Air Bulb and Metal Plate

Now, you need to pull the metal plate upward to remove it from around the air bulb. Grab the previous defective air bulb and pull it straight upward.

If you notice that the air bulb or the metal plate is stuck, don’t worry. You can use a needlenose pliers to remove them.

Step 3: Clean the Air Bulb Seat

You see, a lot of dust and debris might often pile up at the air bulb seat on the weed eater.

If those enter the carburetor, there’s a high chance that they might do great damage to the inside mechanism of the weedeater.

Step 4: Put the Polythene in Place

It’s going to sound weird but this is what you need to do. You need to put the polythene under the metal plate where the air bulb was.

Now, push outside from the hole using your finger. This will create like a ball of polythene and it will act just like the primer bulb.

Step 5: Screw the Metal Plate Back on

You need to screw the metal plate back on now using the two screws to tightly fit it into place.

Make sure that it’s too tight to let any outside air get into that tiny ball of polythene.

Step 6: Press the Polythene Ball Few Times

Now you need the DIY bulb you’ve made to be ready so that you can start your weedeater right away.

As soon as you screw it tightly, you’ll notice the gas piling up inside the ball of polythene and that’s exactly what we want.

All you need to do it keep pressing that little ball for quite a few times till you see bubbles in the carburetor line. Because that’s when you know your weedeater is ready to start.

Now try to start your weedeater. It might not want to start at first, but it’ll start running after a few attempts.

Frequently Asked Questions

Question: Why is my primer bulb not working?

Answer: You see, when your primer bulb isn’t working, it may be a problem with the bulb itself. Also, people often face issues with the fuel lines that feed fuel to the bulb or both. Often fuel lines hardened and cracked and they let in air. That air is what makes it impossible to draw the fuel into the carburetor properly.

Question: Which fuel line goes to the primer bulb?

Answer: You’ll notice the clear pipe which is the fuel intake line, runs from the top of the carburetor. And it goes to the short post on the back of the primer bulb. The blue line a.k.a the return line comes from the long post on the back of the primer bulb and goes into the bottom of the fuel tank.

Question: Why is my carburetor not getting gas?

Answer: The most obvious reason could be the supply of zero fuel at your carburetor. Also, it can be a simple issue like a fuel filter plugged so tight that no fuel can pass through. Nevertheless, a hole in the fuel line on the tank side could also cause the fuel pump to such air instead of fuel from the fuel tank.


Well, now you know how to bypass primer bulb on weedeater with just a simple trick.

However, in the long run, you should grab a new primer bulb from the market and replace it.

And if you feel like that the situation of your weedeater is out of your reach, there’re professionals always ready to take of it.

So, don’t worry and get your weedeater started in no time.