Symptoms Of a Bad Primer Bulb On An Outboard Motor

In order to enjoy using your boat more often, it is necessary to keep your outboard motor in optimum performance.

Detecting the symptoms of a bad primer bulb on an outboard motor early will save you from a lot of stress.

Some of the symptoms of a bad primer bulb includes flat primer bulb, leaking points or loosely connected valves and hose to the primer bulb.

Once a primer bulb is bad, it will affect the overall performance of your boat.

These symptoms are to be detected early to avoid having a faulty boat in the middle of the ocean.

That is why it is very important to know the signs of a bad primer bulb on a boat.

Symptoms Of a Bad Primer Bulb

When a primer bulb fails to function well, it could be a two way issue.

It could be a problem caused directly by the primer bulb.

It could also be as a result of another part of the boat or other components attached to the primer bulb.

A thorough routine check always helps to detect the issue.

These issues that show symptoms of a bad boat primer bulb include;

1) Cold Start Of Engine

When a primer bulb has an issue, one of the signs it shows is that the engine will have difficulty in starting smoothly.

Normally when the it has no issue, starting the engine should be done flawlessly.

But when it develops faults, it will often take time before the engine starts well.

This can be a really big turn off and loss of revenue especially when you are operating a commercial boat.

So if your engine has a delayed or cold start, just press the primer bulb and observe how it is when the engine is off.

If it is soft, then it has an issue or components attached to it has some issue.

Fix it and your boat will be optimally working again as it should.

2) Damaged Fuel Line

When the pressure in the interior of a primer bulb gets low an issue is detected.

This makes the primer bulb to be soft or not too hard when the engine is off.

Typically this is seen as a sign of a bad primer bulb on onboard motor.

But a thorough investigation is always needed to conclude.

This has to do with checking if there is any damage on the fuel line linking to the primer valve.

If the fuel line is bad, it will cause the primer to lose optimal performance.

This is due to the loss of pressure and fuel through the fuel line that is leaking.

Due to this leakage, it affects the optimal productivity of the primer bulb.

3) Prime Bulb Too Soft When Engine Is Off

One of the key indicators of a bad primer bulb is always seen when you hold it.

This is done when the engine of the boat is off.

At a good performance, it is supposed to be hard when the engine is off.

But if it gets soft even when the engine is off, then there is an issue somewhere.

A lot of times this is always a symptom of a bad primer bulb on outboard engine.  

That is why you have to always make sure that you are buying a good one anytime you are replacing it.

This will cut the frequency of it getting bad too quickly.

So if you notice that your primer bulb is soft when your engine is off, you may need to change it to a better one.

This will help the engine perform at an optimal level.

As such, you will also have a nice ride time anytime you feel like driving.

4) Engine Shuts Down Even When Gas Pumps

Engine needs to continuously take in fuel to keep the cylinders firing.

This is what keeps the engine running consistently.

But it does not just need fuel to keep firing, there is a quantity that it needs to keep working well.

If the quantity that is being supplied to the engine is not up to the quantity that the engine needs, it will not work well.

Most times, the engine will shut down due to the inadequate supply of fuel.

This is one of the problems that you will encounter when your primer bulb is bad.

This is because it will limit the volume of fuel that flows out through the exit valve.

When this happens, a lower volume of fuel gets fed into the engine.

This will starve the engine of an optimal volume of fuel to perform well.

As this prolongs, the engine will shut down.

5) Lose Contact Of Primer Bulb Hose

One of the symptoms of a bad outboard primer bulb has to do with how the hose are linked to the primer bulb.

This extends to how tight the fuel line is connected to the primer bulb.

Also it extends to how tight the exit hose that is taking fuel out of the primer bulb is connected.

Any loose connection in any of these hose will bring a problem to the primer bulb.

It will reduce the optimal performance of the primer bulb.

Due to this, the efficiency of the engine will be reduced.

That is why it is very important to make sure that you check the contact points on a primer bulb.

Make sure that the hose that is bringing in fuel to the primer bulb is tightly secured.

This will prevent loss of fuel through leakage.

Also it will prevent loss of pressure in the inside of the primer bulb when the engine is off.

Make sure that you also check the hose that takes fuel out of the primer bulb too.

It should also be tightly held to aid the optimal flow of fuel.

6) Damaged Fuel Line

Most of the times people are too fast to place judgment on the optimal performance of a primer bulb.

Once they touch it and feel that it is soft or flat, they directly crucify the primer bulb of being bad.

But some of the times after a thorough check is done, it is discovered that the primer bulb is still good.

The problem is always attributed to a failed fuel line with leakage.

When a fuel line is leaking, it will also affect the performance of the primer bulb too.

This is because when the fuel line is in a bad condition, it will not be able to supply the optimal volume of fuel.

Some will be loss through the leakage point that exist in the fuel line.

Also pressure is also lost in the process too.

So if you notice that the fuel line is bad, you need to make sure that you change it.

This will help increase the performance of the primer bulb.

This will also result in supplying an optimal volume of fuel to the engine so as to perform well in various levels of acceleration.

7) Leaking Primer Bulb

One of the worse symptoms of a bad primer bulb in outboard motor that shows up is when the primer bulb has a cut.

This can be in the body or at the points at which the hose are connected to take in or send out fuel from the primer bulb.

Due to this cut, the primer bulb will develop leakage.

This will also lead to the loss of pressure in the inside of the primer bulb.

This is seen when fuel starts leaking from the primer bulb.

Due to this, it will not be hard enough due to loss of pressure through the point where the cut exist.

8) Cloaked Or Blocked Primer Bulb

As the years of usage of a primer bulb increases, the debris that exist inside it may also increase too.

There are a lot of factors that contribute to this.

One is due to the quality of fuel that you use.

Another is also due to the quality of filter that you use too.

If the quality of the fuel or filter is bad, it will not be able to trap debris that is present in the fuel.

When this occurs, it might block the primer bulb exit valve if the primer bulb is not kept in a vertical position.

When the signs of a bad primer bulb on a boat shows up like this, it can be taken out and properly cleaned.

This will help take the debris away.

How Do I Know If My Primer Bulb Is Bad

Knowing if a primer bulb is bad depends on how it functions.

This has to do with how the primer bulb feels when touched while an engine is running.

Also it has to do with how it functions too when the engine of a boat is on.

For a primer bulb to function well, it has to be hard when the engine is off.

But if you have a primer bulb that is flat or soft when the engine is off, that shows that there is a problem somewhere.

Can You Repair a Bad Primer Bulb

Repairing a bad primer bulb depends on the degree of damage that is sustained.

If it is an issue like a blocked valve, it can be easily fixed.

This can be done by removing it and washing the inside with fuel to remove the debris.

But if the primer bulb sustains a severe cut that causes a leak, it is better to just replace it with a new one.

Conclusion

Anytime you are making use of your boat, you have to make sure that it is in an optimal performance.

This will help avoid boating casualties that lead to the most fatalities from taking place.

Apart from performing tasks like having a helpful boating pre-departure checklist, you have to make sure that you pay attention to signs of a failed part.

Such includes the symptoms of a bad primer bulb.

Having these things in check will help you have a great time anytime you are driving your boat.

Further Reading

Safety Tips When Fueling Your Boat

Symptoms of a bad fuel pump on outboard motor

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