Hydraulic Oil Leak

An unexpected hydraulic oil leak can cause unwanted downtime and costly repairs. Therefore, it is important to undertake regular maintenance to make sure leaks are found and repaired quickly to prevent severe repercussions…

Leakage in a hydraulic system can result in unreliability, increased energy consumption, increased maintenance costs and overall reduced cost-effectiveness – which can all take a significant toll on your profits. Unfortunately, leaks aren’t always easy to spot – often not until after operation has been negatively affected.

Hydraulic Oil LeakHowever, some hydraulic systems have leaks that have been planned. Manufacturing these type of system is deliberate, as it allows an Original Equipment Manufacturer to record the maximum amount of leakage during normal operation. Deliberate leakage allows a fluid to travel from a highly pressurised zone to a lower pressurised zone to clean and cool specific areas of a component. The fluid is unable to exit, leaving no obvious sign of its existence.

Most leaks are a direct result of wear along the surfaces of hydraulic equipment. However, they can also occur through poor design, inappropriate equipment choice and poor quality control during the manufacturing process. The first obvious signs of leakage could be decreased performance, unreliability and increased working temperatures.

If the viscosity of hydraulic oil is low or the temperature is too high, this may increase the chance of leaking. Untimely wear of surfaces and fluid properties in a component can be a consequence of this. Many original equipment manufacturers recommend a maximum viscosity in order for their equipment to operate fully. Choosing the correct oil and sustaining a sensible temperature to retain this viscosity is usually achieved by the end user.

A hydraulic oil leak can be found in one of two ways:

Infrared thermometers: these are useful for taking unobtrusive measurements of equipment temperature. Abnormal temperatures in relief valves are examples of anomalies that could go undetected, due to the hydraulic system’s cooling or distribution of heat throughout the equipment.

Ultrasonic detection: another recognised method of measurement may be ultrasonic detection. Ultrasonic detection localises the internal leakage, however it doesn’t confirm how much the component is leaking. To gain a better understanding of the hydraulic oil leak, the best measurement would be taken from a flow meter or similar equipment.

It is easier to distinguish a hydraulic oil leak if it is external. Leaks like these should be fixed swiftly, as they could eventually lead to expensive downtime on a production line. In many cases replacing fluid can be a lot less cost-effective than buying brand new oil;  safety and environmental issues also need to be considered, however.

Hydraulic Oil LeakIn order to make it easier to detect an external hydraulic oil leak, dyes that are sensitive to black light are good ways of determining the location of external leaks. This dye is designed to be compatible with both the hydraulic fluid being used and the component surfaces thmselves without contaminating the oil. When mixed with the oil, the dye creates a bright green/yellow glow when exposed to the black light. This enables you to see where the leak in coming from in the hydraulic system.

If you can’t find what you’re looking for then call us or go to our Contact page to enquire online.

Our team has over 100 years’ of technical experience between them. Please refer to our library of  customer testimonials for more information.


Testimonial: Rayne Precision Engineering

I have passed your cards onto a couple of our maintenance contractors and have given you a high recommendation to them both, so hopefully they too will be using in the future. Thanks for helping to get our repair solved so promptly.

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Testimonial: Engineering Solutions

The valve arrived about 9:00am this morning. The service from you and Steve has been first class, so thank you very much. I shall certainly use your services again and recommend you to others. Thanks again and best regards.

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Testimonial: Philippines

We would like to confirm receipt of your shipment for our initial order: PO# 07623. It was a pleasure having started working with you and we hope this is just the start of a good business relationship between our companies. Again, thank you very much and we look forward for more future business opportunities with you.

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Testimonial: The Netherlands

Thank you for your service with selecting the proper pump. Pumps have arrived this morning and they completely conform with the old pumps.

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Testimonial: Abernethy Trust

Please pass on my thanks to Steven for great customer service and his product knowledge; our gang mowers are back up and working.

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Testimonial: Virginia

Please thank your team very much in helping me solve a pump issue. I needed a pump that was manufactured by a company no longer in business, and Steven was able to locate a duplicate that was manufactured by Parker.

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Testimonial: Gwynedd

Thank you, Joanna. Mark’s quote was from a technical discussion which answered many questions that I have been trying to get without success from other suppliers. Please thank Mark for his time and expertise; it was so refreshing to have a knowledgeable person rather than a sales assistant.

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Just wanted to tell you that the pump fits and works perfectly. You were a big help, thank you.

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Testimonial: Lift Company

Hi Mark, Thanks for sorting this out for me so quickly. Absolutely brilliant service… In this day and age it is so rare to come across a company with customer service to this level. Much appreciated.

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Testimonial – Perth

Can you let the boys know that they are providing us with great service, parts and information in all our locations. Your service is prompt and reliable; you’re our “go to” guys when it comes to hydraulics.

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