It’s clear that dealing with hydraulic machinery is not easy, especially when learning how to bleed a hydraulic cylinder without a bleeder valve. You probably do not know what to do when you discover that there is no bleeder valve for releasing the trapped air. We’re here to help at Coastal Hydraulics!
Explaining the Absence of the Bleeder Valve
The designers of each particular hydraulic system have their own reasons for creating this or that machine or mechanism. It means that the absence of a specific valve can sometimes be explained by particular requirements of its operation. In other words, sometimes, a hydraulic bleeder valve may be absent because the manufacturer intended to make the cylinder compact or to minimize production expenses.
However, sometimes the system is made in such a way that it pushes all air bubbles towards the tank. Therefore, you have to use hydraulic lines for air release when no bleeder valve is installed in the equipment.
Our Simple Step-by-Step Guide for Air Removal from a Cylinder
As mentioned, air bubbles always tend to rise upwards within any mechanical fluid system. You have to take advantage of this natural feature. Below you will find the step-by-step procedure for how our professionals perform air removal from a hydraulic cylinder.
Preparing the Cylinder for Effective Purging
Gravity plays the key role in successful air removal process. We position the cylinder in such a way that its ports are located in the upper part. In case of mounted cylinders, we articulate the equipment arm in the right direction. As for the detached devices, they are recommended to be placed in a vice grip so that the ports will be located upwards. This will guarantee that the air pockets will travel toward the connections.
Loosening the Hydraulic Connections Gently
Having positioned the cylinder correctly, it is time to open its connections. We don’t unscrew them completely; instead, we just crack one of the nuts. We always pay special attention to safety measures because opening hydraulic lines is dangerous in terms of injury. We always wear safety goggles and heavy-duty gloves for protection. Moreover, it is crucial to set up a catch pan to prevent fluid spills, especially when working around a hydraulic air bleed valve.
Pumping the Cylinder and Releasing the Trapped Air
After that, we can begin the process of purging the trapped air pockets. First, we cycle the cylinder with low-pressure settings. We pull and push the rod gently, and air bubbles move in the direction of the loosened line connection. Then we start to hear some noise followed by fluid sputtering. It goes without saying that we always continue cycling until we notice that fluid is flowing steadily and evenly.
Securing the Fittings and Checking the Operation
The moment we notice a steady stream of oil from the opened port, we then tighten the line connection. We always clean the surface of the cylinder after purging. We also repeat the cycle for a couple of times to make sure that everything works properly. In case of some problems with movement smoothness, we repeat the process.
Why You Should Consult with Our Experts
If you have doubts concerning the possibility of working with pressurized hydraulic connections, you are welcome to visit our repair center for hydraulic valve repairing. In this case, our skilled technicians will use professional equipment and tools to bleed, diagnose and rebuild your cylinder. Our specialists at Coastal Hydraulics will be able to detect the sources of air entry and repair or replace faulty components.
Frequently Asked Questions About Cylinder Air Release
When Is It Necessary To Bleed A Cylinder?
Our clients often ask how often they need to bleed their cylinders. The answer to this question depends greatly on particular needs of your machinery. Typically, bleeding is required only after the completion of certain procedures, such as replacing parts or flushing liquid.
How Much Oil Loss Can You Expect During The Bleeding Process?
Another popular question is related to oil loss. When you do not have a bleeder valve in your cylinder, some oil is guaranteed to leak while releasing air. Therefore, it is important to keep your fluid supply tanks full.
Is It Safe To Apply Thread Sealant To The Line Connections?
Finally, there is one more aspect that our clients usually want to know. They wonder whether it is possible to put sealant to the cylinder ports. Our specialists strictly prohibit applying ordinary pipes tape to hydraulic devices. Small chunks of this product can become serious contaminants in valves.
Achieving Peak Precision in Movement
As was said above, air is a major obstacle for proper operation of your machinery. Nevertheless, the presence of air pockets is a problem that can be easily solved by purging your equipment. You only need to be extremely careful while working with fluid lines. In case you doubt in your skills, please contact our expert technicians today.
Wayne Rodick is the owner and founder of Coastal Hydraulics, a company built on the principle of “Speed to Recovery.” A U.S. Navy veteran, Wayne developed extensive hydraulic expertise while maintaining F-18 fighter jets, where precision, reliability, and rapid service were critical. Today, he brings that same commitment to excellence to the hydraulic repair industry, leading a team dedicated to delivering fast, dependable repairs that minimize downtime and keep equipment operating at peak performance.