Why Is My Nail Gun Leaking Air? (Solved)

A nail gun leaking air is a bad thing. It will affect the operation of the nail gun and let the nail gun shooting blanks, and nail gun hissing can be extremely irritating and frustrating.

But how do you deal with this? You must first determine the cause. Fortunately, I can assist you because I have already solved this problem with my nail gun.

There are several possible causes for a nail gun leaking air. In many cases, an o-ring will be damaged and must be replaced. A damaged pistol ring, valve, or a broken gasket or collar between two parts are all possible causes.

Thanks to this nail gun leaking air problem that I experienced myself, I can now help you on your way to solving the same problem you experience with your nail gun.

I’ll look for the right cause with you in the first part of this article, and then I’ll walk you through how to solve this problem step by step in the second part.

You can be confident that the nail gun hissing problem has been resolved and that annoying sound has been eliminated by the end of this article.

Disclosure: At zero cost to you, I may get commissions for purchases made through links in this post. I earn from qualifying purchases as an Amazon associate. Products featured are selected based on quality, performance, and reputation, regardless of affiliate relationships.

Identify Where the Nail Gun Is Leaking Air

Nail Gun Leaking Air from the Exhaust

Your nail gun is leaking air from the exhaust because the pistol ring is damaged, or the O-ring is not sealing properly, or worse, damaged.

Damaged pistol ring

Inside the nail gun is a piston ring that seals the piston to the cylinder. By firing again and again, and stressing this piston ring, it can wear out and the seal will be lost. You will recognize this by air leaking from the exhaust of your nail gun.

A damaged piston ring can only be repaired by replacement, later in this article, you will see how to do this.

The O-ring was not properly sealed

The o-ring around the seal at the top of the cylinder not sealing properly is a common problem. Don’t be put off, though, because this too is an issue that the handy DIYer can handle. I’ll show you how to do this in a minute.

Nail Gun Leaking Air from the Trigger

If your nail gun leaks air from the trigger, this may be because of a worn O-ring rubber, or damage to the trigger valve due to wear. read on, because I will show you how to find the leak.

Damaged O-ring

O-rings are placed on the trigger valve to prevent air from leaking so that the nail gun can work optimally. These O-rings are designed to seal the space around the overhead valve and are often made of rubber or synthetic rubber. However, this rubber is subject to the conditions (drying through the air) and wear can therefore occur. With this wear, the O-ring will no longer seal, causing the nail gun to leak air from the trigger.

The only thing you can do in case of a worn o-ring is to replace it. Don’t try to fix it with slicone or any kind of sealant, you might do more damage with it than it already was. Later in this article I will show you through a simple manual how to replace the O-ring yourself.

Damaged valve

The trigger of a nail gun works in such a way that when you press it there is an internal short but powerful blast of air that pushes to release.
the piston which in turn fires the nail. If you feel the trigger leaking air when you pull the trigger, then you can be pretty sure it’s the trigger valve that is damaged. You will experience this problem more easily with older nail guns that have been pulled the trigger many times. In other words, this is a wear problem.

Because of this wear, you must replace the trigger valve. I will also come back to this task later in this article

Nail Gun Leaking Air from the Top

This last problem could be caused by one of three factors. I’ll go over them briefly below in order for you to identify and address the underlying cause.

Gasket failure

Gaskets are used to close the gap between two components. These gaskets have the appearance of a thin layer and are made of rubber, metal, or cloth/paper. The gasket is faulty if there is air leakage between the two parts. Gaskets are less likely to wear and break than o-rings unless the parts have been disassembled numerous times.
If your nail gun’s gasket breaks, the only thing you can do is replace it right away.

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A broken Collar

The most common reason is a broken collar. The collar functions as both a seal and a spacer collar for the nail guns. This is a neoprene component that can degrade over time.

Check the collar first if you have an air leak in the tip of your nail gun. If it is broken, you must replace it.

The seal is leaking

You might also notice air escaping from the top of your nail gun. This could be due to a broken seal. This seal prevents air from leaking between the piston and the cylinder. However, it can wear out and crack over time, necessitating replacement to keep the engine running smoothly.

How Do You Fix a Nail Gun Air Leak?

Sealing an air leak is actually not that difficult. You will be more likely to let yourself be held back by the thought that you cannot do this yourself. However, the truth is reversed. Below, you can find step-by-step how to solve all nail gun blowing air problems discussed above.

Whatever issue you want to solve, always disconnect the nail gun from the compressor and remove all nails from the magazine. This way, you are safe that nothing can happen.

Fixing the Nail Gun Leaking Air from the Exhaust

You’ve seen before that a nail gun leaking air from the exhaust is because the pistol ring is damaged or the o-ring is not sealing well enough.

In this part I will tell you how to solve these two problems so that the nail gun no longer leaks air through the exhaust.

How to replace the Pistol ring

Replacing the pistol ring may sound like a daunting task, but these steps make it so easy:

  • Remove the cap from the nail gun.
  • The next step is to remove the plunger from the nail gun.
  • Subsequently, you can take the piston ring off the piston.
  • Now you can mount the new piston ring on top of the piston. It is better to apply a small amount of lubricant to the piston ring. always be careful when installing the piston ring so that it does not break.
  • When putting the assembly back into the gun, pay close attention to the grooves in the driver. This is important if you want the nail gun to work as before.
  • Now put the piston back in the cylinder.
  • Attach the gasket to the top of the gun and install the main valve.
  • Reinstall the overhead cover and tighten the screws.

How to seal the o ring

If the O-ring does not seal, this does not immediately mean that you will have to replace it. You only need to lubricate the O-ring. If the lubrication steps below do not help, you can still replace the o-ring.

  • To lubricate the o-ring, stretch it slightly to loosen it and allow the lubricant to reach the entire o-ring
  • Now apply the lubricant, but make sure it is only on the o-ring, and you don’t a-lubricate the whole thing. There is a good chance that dust would stick here, which could be detrimental to your nail gun in the longer term.

Fixing the Nail Gun Leaking Air from the Trigger

When you have a nail gun blowing air from the trigger, you can easily repair this yourself by replacing the O-ring or replacing the trigger valve. In this section I explain step by step how you can do this.

How to Replace the O-ring

If you need to replace an O-ring, I advise you to always look for an original O-ring set. This way you are always sure of a perfect repair.

Replacing the o-ring is very easy to do in just a few steps that I share with you below:

  • Start by loosening the bolts on the top of the nailer and remove the old gasket.
  • Remove the grommet on the trigger side and push out the pin or pins. Take out the trigger.
  • Depending on the model you have, the trigger valves may be bolted or attached with roller pins. Remove these.
  • Clean the inside of the housing. use the supplied oil if necessary. (you can also use wd40)
  • Replace the outer O-ring and lubricate it lightly with lubricating oil.
  • Now also remove the inner O-ring and replace it .
  • Now put the parts back together.
  • Tighten until the plunger is flush with the top of the saucer.
  • Please do a test to see if everything is working properly. For safety, keep the nail gun as far away from you as possible and wear protection.

How to Replace the trigger valve

if the trigger valve is damaged, replacement is the only solution to this problem. To replace the trigger valve, use the following steps:

  • Remove the retaining pin from the valve first.
  • Once the valve is removed you can remove the trigger valve.
  • Before installing the new valve body, apply a thin coat of the included grease to all O-rings.
  • Carefully insert the valve into the bore. Keep in mind that you hold it perpendicular to the valve body. this will prevent the O-rings from tearing.
  • Insert the locking pin back into the hole.
  • The final step is to hold the trigger in place, making sure the holes line up. then gently tap the roller pin into place.

Fixing the Nail Gun Leaking Air from the Top

In this section, I’ll walk you through all of the steps for the three issues you might encounter with a nail gun leaking air from the top.

How to replace the gasket

Remove the screws to separate the parts.
Remove and discard the gasket. Do not attempt to restore or reuse.
Install the new gasket after cleaning the two mating surfaces.
Reassemble the parts and tighten the screws. I always use the star technique (at least that’s what I call it) for any part that requires multiple screws. I’m going to gradually tighten the screws that are opposite each other. I draw a star to ensure that the pressure on the gasket is evenly distributed.

How to replace the collar.

Remove the screws from the gun cap.
Remove the old collar with care.
Replace the collar.
After tightening the screws, replace the top (preferably again using the star technique I explained just now).

How to change the seal.

First, remove the top cover.
When the top cover is removed, look if you see any wear and damage on the seal.
Replace the seal, and install a new gasket between the housing and the top cover.
Replace the top cap and carefully tighten the screws wit the technique I described above to avoid damage.

Frequently Asked Questions

Should O-Rings Be Lubricated?

O-rings must always be well lubricated, not only when installing, but also in between when doing maintenance. This ensures the flexibility of the rubber so that it can always ensure the best seal.

Is Wd 40 Good for O-Rings?

If you don’t have a lubricant that is specifically used for maintaining the nail gun, you can use WD40 as an alternative to lubricate o-rings. Always check the manufacturer’s instructions so that you are very sure that it is safe to use.

Can You Put Vaseline on O-Rings?

Vaseline should never be used on o-rings. The petroleum jelly will eat away at the rubber, causing the o-ring to wear out faster. To keep them soft, always use a lubricant based on Teflon or silicone.

How to Avoid Nail Gun Air Leaking

Leakage can be postponed by giving the nail gun the best care.
Proper maintenance is the most important concern. Because a lot can be said about this, I wrote a separate article earlier. Be sure to check out How To Maintain A Nail Gun (2-Minute Guide) and follow all the steps outlined therein to have a nail gun that works well every time.

Another thing you can do to avoid leaks is to always store your nail gun properly. As a result, not only the nail gun cannot be damaged, but also the internal parts of the nail gun.
All tips for the correct storage of the nail gun can be found in my article, How To Store Nail Guns? Best Advice To Keep Them As New

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Is your nail gun leaking air, then I hope this article gave you the answers you needed to fix this problem soon.

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Christophe, founder of Christofix.com
Woodworking | DIY | Home decoration

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