Air Compressor Leaking Air – How Can You Fix It

You must be wondering why your compressor always lacks sufficient air. There are several reasons for it. Today I will talk about the reasons behind why is your air compressor leaking air. I will also help you on how you can fix this problem, in this article. So buckle up and let’s start.

Possible Causes of an Air Compressor Leaking Air

Directly from the Tank

If the air tank, where the compressor holds the air, has some holes then the air will leak directly from the tank. The holes may occur due to heavy-duty use of the compressor. It can also occur if the tank is really old.

Holes are not the only reason. The tank is connected to the hose. In the joint, if the connection is not sealed properly, the tank will also leak air in this case.

Image Shows the Tank of an Air Compressor

Problem with the Unloader Valve

The unloader valve of a compressor is attached with the pressure switch. When the pressure switch reaches the cut off pressure, the valve closes and seals the air inside.

However, if the unloader valve of your compressor is quite old, then it won’t be able to seal the air properly as the rings on the valve becomes loose. Hence, your air compressor unloader valve starts leaking air.

Pressure Switch Diaphragm Broke

If the unloader valve has no problem, yet the air is leaking from the valve area, it is due to the pressure switch. Just like the regulator, the pressure switch also has a diaphragm inside it. In time the diaphragm gets cracked or gets a hole in it by rusting. In this case, the air compressor pressure switch starts leaking air.

The Check Valve is Damaged

Another cause of an air compressor leaking could be the damage of the check valve. The check valve is the valve that prevents the back-flow of air into the tank. However, if the disc of the check valve is broken or if the body of the check valve is damaged, then it will leak air.

Regulator Blowing out Air

Regulators are usually installed to the discharge coupler of your compressor. There is a flexible diaphragm inside the regulator which holds the air. If you are using the compressor for a long time, this diaphragm gets cracked. This will cause the air compressor leaking air from regulator.

The Obvious Cause

Of course, the tube or the compressor hose is the most delicate part of a compressor set. When there is a leak on the tube or the hose, the compressor will surely leak air. But this will only leak while the compressor is operating. If the compressor is turned off, the hose will not leak.

Ways You Can Detect the Air Leak

Simply Hear the Sound

You can simply identify the leak by hearing the noise of the leaking air. Usually, air leaking produces a simple noise which can be heard by anyone. It is the easiest technique but it helps if there are one or two leaks.

If there are a lot of leaks in different places of the compressor then you need other methods to find the leaks. Because then you cannot identify all the leaking points as the sounds of each leak point will collide.

Use Soap or Detergent

Have you ever seen how the leaks of a tire tube are identified? Soaps or detergents (which can make bubbles) are used on them and the air is blown inside the tube. The place where the bubbles are coming out is the point of the leaking.

You can use this same old technique to find the leaks in your air compressor tubes or valves. For example, you can put some soap around the valves and the hose. Then start the compressor, you will find bubbles in the leaking area.

Use Ultrasonic Leak Detectors

Sometimes you won’t hear the sound of air leaking with your ear. In this case, an ultrasonic leak detector can help. This is a device built with directional microphones, audio filters, and amplifiers.

An example of an ultrasonic leak detector
Credit: Wikimedia Commons

This device will identify sounds produced by the leak of air as it can capture high-frequency hissing noises. Ultrasonic leak detectors are really compact and they have microphones and a digital display that will help you to find the leaks easily.

Fixing Air Leak on Your Compressor

If your air compressor is leaking air you can follow these steps for fixing it.

Tighten the Connections

The first and foremost way to fix an air leakage problem is for you to tighten the connections. All the valves are connected to different parts of the compressor. Some are connected to the hose, others are directly connected to the tank.

Whichever it is, you must properly tighten all the connections in order to prevent air leaking from your compressor.

Repair the Broken parts

Repairing the parts that are broken is another great way to fix this problem. For example, if you find air leaking from the pressure switch, then the switch is broken. Check if the diaphragm inside the switch is broken or not. If it is broken, repair the pressure switch by using a new diaphragm.

Replace the Damaged Parts

You can also replace the damaged parts to fix air leaking problems too. If the drain valve or the unloader valve of your compressor is too old, then you cannot repair this part. In this case, the best option for you is to simply replace this part.

Tips on Preventing Air Leaks

Here are a few ways you can use to prevent air leaks in your compressor.

Get Well-Built Equipment

You should get an air compressor with high quality built material so that it doesn’t get damaged easily. This doesn’t mean the compressor have to be too expensive or something. You can get a good quality air compressor with a fair budget too. Just make sure, all the parts are well built when you buy one.

Lower the Pressure

If you do not need much pressure for your work, then do not use high pressure. The valves and the pressure switch function by depending on the pressure level. Regular use of high pressure leads to quicker damage to these parts. So, it is better not to use high pressure when it is not necessary.

Check & Seal the Parts Properly

Every time you turn on and turn off the compressor, make sure you have sealed all the parts properly. Sometimes accidentally some parts are not sealed properly. This leads to leakage of air. So keep this part in mind.

A fully sealed air compressor
Credit: Flickr


How to plumb up your air compressor to keep from leaking out overnight?

Follow the steps given below and you can keep your compressor from leaking out.

  • Identify the part from where the air is leaking. Follow the given instructions above to identify the leakage.
  • After identifying the leakage, either repair or replace the part that is leaking the air. If the check valve is leaking air see if you can fix it. If it is not fixable replace it.

This is the simplest way to solve this problem overnight.

Why is the water trap on the air compressor leaking?

The water trap on the air compressor leaks only when the valve is not functioning properly. The valve is obviously damaged. If not, then you should check if you have tightened or sealed the valve properly or not.

How to fix a leaking air compressor tank?

If you find the air is leaking from the tank, there are two possible reasons. The tank top is not tightened properly, or the tank has holes on it.

  • If the tank top is not properly tightened, you simply tighten the top. That’s all.
  • And if you identify holes, you can simply use sealants to cover the holes. This won’t last for days, but you can use it till you get a new tank.

How do I know if my car air compressor is leaking?

You can use the same techniques given above to find if your car air compressor is leaking or not. When the air compressor leaks, you simply see that there is not enough pressure coming from the compressor.

Why is my compressor leaking air out of the oil dipstick hole?

When a compressor is leaking air out of the oil dipstick, this means the pump has a problem rather the dipstick. There is a hole in the cover of the dipstick that allows air into the sump.

But there is a piston seal in the pump cylinder that keeps the air out. However, if there is a problem with the seal, then air will leak from the dipstick hole.

Why would my drain valve on the air compressor be leaking?

If the drain valve is old or if the disc in the valve is cracked or if there are holes in the valve, then the drain valve usually leaks.

How do you fix a leaking air hose on your compressor?

If your hose is leaking, first you have to identify from where in the hose is the air compressor leaking air. Then you can simply use duct tape or regular tape to fix the hole. Note that this won’t last for a long time so it is better you replace the hose with a new one.

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