Hydraulic pumps fail for the same three reasons in Australia as anywhere else – Excess heat, Contamination, and Cavitation.

But the way they’re used and maintained in Aussie conditions (heat, dust, heavy machinery, long duty cycles) makes good practice even more important.

Why Hydraulic Pumps Fail (And How to Prevent It)

Like any mechanical component, hydraulic pumps will let you know when they’re not happy. If they’re not maintained properly, you’ll cop breakdowns, downtime, and some hefty repair bills. With a bit of know‑how and regular attention, you can prevent most failures and keep your machines,  trucks and building services running reliably.

The main culprits in Australian hydraulic systems

Even though modern pumps are robust, they’re still vulnerable to a few familiar enemies.   No maintenance, tough operating conditions (Melbourne can be dry and hot) and design shortcuts often show up as one or more of the following problems.

1. Excess heat

Across Australia – from metro sites in Melbourne to mining and civil jobs in the regions – high ambient temperatures and long operating hours mean hydraulic systems are constantly battling heat. Some warmth is normal, but sustained high oil temperature is one of the quickest ways to cook a pump.

Why heat is a problem

When hydraulic oil gets too hot, it starts to break down and lose viscosity. That means less effective lubrication, more metal‑to‑metal contact, and accelerated wear on the pump and other components. Seals can harden, crack or deform, leading to internal leakage, external oil leaks, and eventually outright failure. On mobile equipment, once the oil gets hot, performance drops and operators tend to “push through”, which only makes things worse.

How to prevent excess heat

• Size the reservoir properly - Make sure the tank is large enough for the duty cycle and environment the machine is working in. A properly sized reservoir gives the oil time to shed heat before returning to the pump.

• Fit and maintain oil coolers - Where systems run hard (e.g. access equipment, compactors, elevators, car stackers), oil coolers are essential. Keep fins and tubes clean and ensure the cooler is sized for peak summer loads, not just mild weather.

• Monitor oil levels and viscosity - Running low on oil or using the wrong grade for Australian temperatures leads to overheating. Follow the manufacturer’s recommendations and adjust for the climate and operating hours.

2. Contamination

Dust, dirt, moisture and metal particles are a fact of life on Australian sites and in plant rooms, and they’re one of the biggest causes of hydraulic pump failure. Once contaminants get into the oil, they circulate through the system and quietly chew everything up.

Why contamination is dangerous

Abrasive particles score pump housings, pistons and gears, increasing clearances and internal leakage. Water and chemical contamination attack surfaces and alter the oil’s properties, reducing lubrication and promoting corrosion. Over time, efficiency drops, temperatures rise, and the pump works harder just to do the same job.

How to keep hydraulic oil clean

• Change filters on schedule - Use the correct suction, pressure and return filters and replace them at recommended intervals, not just when there’s a breakdown. Blocked or overloaded filters let contaminants bypass straight into the pump.

• Use quality, compatible hydraulic fluids - Cheap or incorrect fluids can separate, foam, or react with seals and hoses. Always use the fluid type and grade specified for the equipment, and stick to reputable brands commonly used in Australian industry.

• Protect fill points and breathers - Keep reservoir caps, breathers and fill points clean. On dusty sites or in plant rooms, fit high‑quality breathers so you’re not sucking in airborne dirt every time the tank “breathes”.

• Inspect and replace seals - Worn cylinder rods, pump shaft seals and hose connections are common ingress points. Routine inspection and timely replacement prevent contamination from entering in the first place.

3. Cavitation

Cavitation is a silent killer of hydraulic pumps. It occurs when the pump doesn’t receive enough oil at the inlet, creating vapour bubbles that collapse under pressure and pit internal surfaces.

Signs of cavitation

A cavitating pump often runs with a distinctive whine or growl, and operators may notice a loss of power or slow response. You may also see foamy oil in the reservoir, indicating air or vapour in the fluid.

How to prevent cavitation

• Increase inlet line size where needed - A larger, correctly sized suction line helps maintain steady flow to the pump, particularly on longer runs or high‑flow applications common on Australian mobile plant.

• Remove unnecessary restrictions - Avoid sharp bends, elbows, strainers or fine filters on the inlet side. Every restriction increases the chance of localised low pressure and vapour formation.

• Position the reservoir above the pump - Where design allows (especially in fixed plant and building services), keeping the tank above the pump provides positive head, improving inlet conditions and reducing cavitation risk.

• Check fittings and connections - Loose fittings on the suction side can draw air into the system. Regularly check and tighten connections, especially on equipment that sees a lot of vibration and movement.

Prolonging the life of your hydraulic pump in Australian conditions

Preventing pump failure isn’t just about reacting when something breaks; it’s about building good habits into your system design and maintenance routines.

• Monitor oil quality and temperature - Make oil sampling and temperature checks part of your standard service. Spotting rising particle counts or temperature trends early can prevent a major failure.

• Schedule routine inspections - Regularly inspect pumps, hoses, fittings and cylinders for leaks, wear and unusual noise. A simple visual and audible check on each service visit can save thousands in downtime.

• Use predictive maintenance where possible - Modern hydraulic systems often include pressure, temperature and flow sensors. Hooking these into a monitoring system or logging key readings during service lets you identify changes in performance before they turn into breakdowns.

• Train operators and site staff - Many failures start with how equipment is used day‑to‑day. Basic training on warm‑up procedures, avoiding overloading, and reporting early signs (noise, heat, leaks) makes a big difference in the real world.

Final Thought

The quality of your components certainly matters in avoiding pump failure. However it’s quarterly maintenance that makes the biggest difference. That’s where a trusted expert like Flotek comes in. As the highest rated hydraulics company in Melbourne, our Technicians are trained to know everything about hydraulic pump maintenance. With over 50 years of proven experience, and exclusive partnerships with Hydac and Enerpac, Flotek can ensure your hydraulic pump continues to operate at it’s best for many years.

Find out about our quarterly Hydraulic System Inspection (HSI) program. A Flotek Technician will inspect your hydraulic system each quarter, ensuring everything is working to it’s optimum. Because we know that Melbourne businesses can’t afford downtime.