Outboard Primer Bulb Won’t Fill? Here Is Everything You Need To Know

The priming bulb is a modest piece of equipment, but it has a very significant function. On a small contemporary engine, it could just appear to be another piece of plastic, but its purpose is to pull fuel from the reservoir and deliver it straight to the carburetor.

These kinds of items occasionally have a tendency to stop functioning altogether. Fortunately, this is a great illustration of a task you can accomplish quickly from the convenience of your home. Today, we’ll demonstrate the process of an outboard primer bulb won’t fill and show you how to fix it

Why Outboard Primer Bulb Won’t Fill

If the priming bulb isn’t working, there may be an issue with the bulb, the fuel lines that supply the bulb with gasoline, or perhaps both. Primer bulbs and tubes will ultimately harden, break, and degrade over time since they are both constructed of flexible plastic or rubber. A primer bulb that no longer has flexibility responds differently than a fresh one. Fuel lines follow the same rules. When they get hard and break, air can enter, which interferes with the carburetor’s ability to suck in the necessary amount of fuel.

Because it might be damaged, your priming bulb won’t be gassed up. Fuel lines that have been swapped or damaged may potentially be to blame. Additionally, the carburetor or hoses might be obstructed. However, worn-out ring seals and check valves are occasionally the other causes. Moreover, gasoline line connections are faulty.

outboard primer bulb won't fill

Primer bulbs and carburetors are still utilized in tiny engines, as we already know. Consider lawnmowers, leaf blowers, and string trimmers.

Now, some of them could be powered by 2- or 4-cycle engines. The whole crankshaft rotation caused by the pistons is referred to as the cycle or stroke. Primers exist in various sizes for this reason. Depending on the tools you’re employing. They still serve the same function, though. And it’s to fill the carburetor with gasoline for combustion.

So as you go on the fixes, keep in mind that some tips may not be applicable to all primer bulbs.

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How To Fix Primer Bulb Not Filling

The most frequent issue individuals have with priming bulbs is that occasionally they will just stop filling. They’ll experiment with it, but they almost never succeed in getting the desired outcome. The problem is that if it is left in this state, it may have a variety of unintended consequences.

Therefore, it’s better to think ahead and be aware of all the possible solutions. This article will demonstrate a variety of techniques for identifying and resolving the issue. Don’t worry if you don’t happen to have any expertise correcting stuff like this.

You don’t need much to solve this particular issue; all you need is the will to learn and try. You won’t be asked to participate in anything advanced. After saying that, let’s get started with our first recommendation.

1. Possibly air leak

This is possibly the most frequent cause of the bulb not functioning properly out of all the possibilities. The intake line has most likely developed a leak, which is the root of the issue. Alternately, if the intake line is the incorrect size, this may also occur. It’s also possible that the filter line is not buried beneath the fuel in the tank.

You may just reach for a cup of petrol and pour it in first. This is to see if it will continue to draw gasoline if the level is raised. If not, we must go to the following phase.

2. Try to giving the bulb a press

Sometimes, the only way to make things right is to just press the bulb down so it can function. You should strive to press it down while keeping one or more fingers on the portion of the line that connects to the tank itself, to further explain this. Simply let go of the bulb again after that.

This advice generally works, however there is a risk that it won’t the first time you attempt it. Due to this, we advise you to test it a few times before continuing.

Hopefully, the bulb will start drawing gasoline shortly. If not, it’s possible that the lines are all backwards. If so, you will have to straighten them up once more.

3. The primer might just be faulty

There is a slight possibility that the primer may have acquired a flaw if nothing has so far worked. I looked through the message boards and forums, and it seems that quite a number of you have experienced this.

Of course, it is always worthwhile to investigate to determine if this is the real reason. We avoid wasting away perfectly fine components in this way.

Even though it’s not ideal, we advise you to try using a different priming bulb. If doing so solves the issue, you will know that the bulb was to blame.

4. Have the fuel lines replaced

Unfortunately, that would suggest that you could need to replace your fuel line with a new one if changing the primer didn’t help to resolve the issue. In reality, according to the majority of publications, you must replace the fuel line and priming bulb simultaneously.

The first step in changing your gasoline lines is to remove the outdated ones. This ought to be simple enough. The new lines must then be the exact same size, therefore you must use them as a guide.

You can swap in the new for the old after you are absolutely certain that they match. Of course, it would be wise to seek expert advice if you were unsure. This can end up being the best move if you have no idea what you’re doing.

How To Prime Up Fuel When Primer Bulb is Air Locked

Primer bulbs should also be used if the fuel spills too far back into the tank. Without removing it, the priming bulb won’t be able to suck it up.

When the priming bulb airlocks and doesn’t appear to be receiving any fuel:

  • Disconnect the fuel line from the engine side of the bulb. With the arrow pointing to the side where you pulled the hose off.
  • Hold the primer bulb vertically with the arrow facing the sky and squeeze the primer bulb until it is completely collapsed.
  • Then, stick your finger on the hose barb.
  • Let go of the primer bulb.
  • Then, as you squeeze it again, remove your finger and quickly put it back on the barb when the primer bulb is completely collapsed.
  • Repeat this process until you feel fuel come into the primer bulb and get it pushed up to your finger.
  • Then reconnect the fuel hose on the bulb and prime that bad boy up!

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