30 June, 2026

When the thermometer exceeds 35°C on the job site and the asphalt seems to melt under the tracks, a poorly prepared excavator can become a very expensive problem. Overheating breakdowns, hydraulic failures, and premature component wear are situations repeated every summer in Spain, especially in regions like Andalusia, Extremadura, or the interior of Castile, where July and August temperatures frequently approach 45°C. The difference between a machine that lasts the entire summer campaign and one that stops mid-day usually isn't the brand or model: it's the prior preparation.

A good summer preventive maintenance plan for excavators reduces unscheduled downtime by up to 40%, according to data from manufacturers like Caterpillar and Komatsu published in their technical reports. And the best part is that most necessary actions do not require large investments, but rather consistency and knowledge. Here is what truly works.

Importance of Summer Excavator Maintenance

Summer is not just heat: it means suspended dust, longer working days, and harder ground. This combination punishes excavators in a way that simply doesn't happen during the rest of the year. Many fleet managers assume that if the machine worked well in spring, it will endure summer without adjustments. This is a mistake paid for with high repair bills and missed project deadlines.

 

A well-designed summer maintenance program not only prevents breakdowns; it extends the lifespan of critical components such as hydraulic pumps, engines, and transmissions. According to the Spanish Association of Machinery Manufacturers (ANMOPYC), the average cost of a major repair due to overheating is around 8,000 euros, not counting machine downtime hours. Investing between 500 and 1,200 euros in preventive inspections before June is, quite simply, economic common sense.

Impact of High Temperatures on Operating Performance

When the ambient temperature exceeds 38°C, an excavator's engine works with a very narrow thermal margin. The cooling system operates near its limit, hydraulic oil loses viscosity faster, and the ECU's electronic components can generate error codes due to excessive heat. The result is a power loss that can reach 10-15% compared to nominal performance.

 

Experienced operators notice it immediately: the machine responds more slowly, excavation cycles lengthen, and fuel consumption rises. This performance drop is not a factory defect, but the engine protection system's response to excessive temperatures. If ignored, the next step is an automatic shutdown due to overheating or, worse yet, irreversible internal damage to the engine block.

Inspection of the Cooling System in Heavy Machinery

The cooling system is the first line of defense against heat. A complete inspection before summer arrives should be mandatory for any fleet, regardless of size. It is not enough to check that the fan spins: every component of the circuit must be verified to ensure the assembly operates with the efficiency the manufacturer designed.

 

The cooling system inspection in heavy machinery includes several points that are often overlooked. The intercooler, for instance, tends to accumulate dust and dirt between its fins, reducing its thermal exchange capacity without showing visible signs until the problem is severe. The same happens with the hydraulic oil cooler, which in many excavators shares space with the main radiator and suffers from the same clogging due to dust and debris.

Cleaning Radiators and Controlling Coolant Levels

Cleaning the radiator with low-pressure compressed air (never above 2 bar to avoid damaging the fins) should be done at least every two weeks during the summer months. On highly dusty job sites, the ideal frequency is weekly. The direction of blowing matters: always from the inside out, contrary to the normal airflow direction, to expel accumulated dirt.

 

The coolant level must be checked with a cold engine, verifying that the antifreeze-coolant concentration remains between 40% and 50%. A lower concentration reduces the boiling point of the mixture and increases the risk of cavitation in the water pump. Using tap water for top-offs is a frequent mistake: lime and dissolved minerals accelerate internal corrosion of the circuit.

Inspection of Hoses and Thermostats

Cooling hoses suffer especially from the heat. Rubber ages faster when continuously exposed to extreme temperatures, and a hose that looks to be in good condition on the outside may have internal micro-cracks that will cause a sudden rupture. Manual inspection, squeezing the hose by hand to detect soft or swollen areas, remains the most reliable method.

 

The thermostat is another component that deserves special attention. A thermostat that does not open completely restricts coolant flow and causes localized overheating in the engine block. Replacing it every two years or 4,000 working hours is a practice recommended by most manufacturers, and its cost rarely exceeds 60 euros—an insignificant figure compared to the consequences of a failure.

Protecting Hydraulic Components Against Extreme Heat

The hydraulic system is the heart of any excavator, and heat is its worst enemy. When hydraulic oil temperature sustainably exceeds 80°C, joints and seals begin to degrade, valves lose precision, and the risk of internal leaks increases exponentially. Protecting hydraulic components against extreme heat is not an option; it is an operational necessity.

 

A point that many technicians neglect is the condition of the hydraulic tank. In summer, thermal expansion of the oil can cause the level to rise above the maximum mark if it was filled cold. This causes excessive pressure in the return circuit and can damage the tank seals. The correct procedure is to verify the level with the oil at working temperature, between 50 and 60°C.

Monitoring the Viscosity and Quality of Hydraulic Oil

Hydraulic oil loses viscosity with heat, and oil that is too fluid does not properly lubricate pumps or maintain the necessary pressure in the actuators. Taking oil samples every 250 hours during the summer and sending them to an analytical laboratory allows problems to be detected before they become breakdowns. The cost per sample is around 25-30 euros, a minimal investment.

 

If the analysis reveals that viscosity has fallen below the range specified by the manufacturer, switching to a higher SAE grade should be considered. Many operators in southern Spain switch from an ISO VG 46 oil to an ISO VG 68 from June to September, with excellent results in terms of protection and performance.

Best Lubricants for Excavators in Hot Climates

Selecting lubricants for summer goes beyond hydraulic oil. Engine oil, transmission lubricants, and general greases must adapt to real thermal working conditions. A 15W-40 engine oil that works perfectly in winter may fall short in summer if the excavator operates at full load for eight consecutive hours in a 42°C ambient temperature.

 

The best lubricants for excavators in hot climates are those with a synthetic or semi-synthetic base, which maintain their thermal stability at higher temperatures than conventional mineral oils. Brands like Shell Rimula, Mobil Delvac, and Repsol Diesel Turbo offer specific formulations for heavy machinery in extreme conditions, with reinforced anti-oxidant additives that delay oil degradation.

Selecting High-Temperature Greases for Joints

The joints of the arm, boom, and bucket need greases capable of staying in place when the metal reaches surface temperatures of 90-100°C. Conventional lithium greases tend to liquefy and run off at those temperatures, leaving the joints unprotected. Lithium complex or polyurea greases with a dropping point above 260°C are the correct choice for summer.

 

The greasing interval should also be shortened. If greasing is done every 10 working hours during the rest of the year, it is advisable to do it every 8 hours in summer. It seems like a minor detail, but the difference in bushing and pin wear at the end of the season is remarkable: up to 30% less wear according to data from workshops specialized in public works machinery.

Inspection of Tires and Tracks Due to High Temperatures

The inspection of tires and tracks due to high temperatures is an aspect that often takes a back seat to the engine and hydraulics, but undercarriage failures can immobilize an excavator just as quickly. Tire rubber softens with heat, and metal track chains expand, altering their tension and accelerating wear on rollers and idlers.

 

On wheeled excavators, hot asphalt can raise tire temperatures above 70°C, a threshold that accelerates compound aging and increases blowout risks. Parking the machine on dirt or gravel instead of asphalt during breaks is a simple measure that significantly reduces this risk.

Managing Tire Pressure and Track Tension

Tire pressure should always be checked when cold, first thing in the morning before starting. Operating heat can increase pressure by 10 to 15% compared to the cold reading, and adjusting pressure while the tire is hot leads to under-inflation. Following the manufacturer's specifications to the letter is essential.

 

For tracks, correct tension is verified by measuring the track sag in the upper section between the drive sprocket and the idler. Excessive tension due to thermal expansion overloads the lower rollers and can cause link breakage. Slightly loosening the tension at the start of the day, when the chain is still cold, compensates for the expansion that will occur during the central hours of the day.

Care Protocols for the Operator and the Cabin

A well-maintained excavator needs an operator in good condition. Heat strokes are a real risk in poorly air-conditioned cabins, and an operator fatigued by heat makes more mistakes, reduces productivity, and increases accident risks. Taking care of the cabin is taking care of the person working inside.

 

Installing exterior sunshades on the front and side glass reduces the interior cabin temperature by 5 to 8°C, even with the air conditioning running. Having fresh water accessible inside the cabin and establishing mandatory breaks every two hours are measures that any responsible company should implement during hot months.

Maintenance of the Air Conditioning System and Filters

The cabin filter should be replaced at the start of summer and checked every month. A clogged filter reduces cold airflow and forces the compressor to work harder, increasing fuel consumption and shortening system life. Checking the R134a or R1234yf refrigerant gas charge is just as important: a low charge of even 15% noticeably reduces cooling capacity.

 

The door and window seals of the cabin also deserve inspection. A damaged seal lets hot air and dust in, canceling out part of the air conditioning's work. Replacing these seals costs little and makes a real difference in operator comfort and safety during the toughest summer days.

Preparing the Excavator for Summer: An Investment That Pays for Itself

Everything invested in preparing machinery for the hot months is recovered many times over in availability, performance, and component lifespan. It doesn't take an extraordinary budget: it takes a plan, a schedule, and the discipline to follow it. Companies that integrate these summer reviews into their annual maintenance program see clear results in their operating accounts.

 

High temperatures test all systems of an excavator, from the engine to the hydraulic circuit or the undercarriage. Anticipating with a specific summer preventive maintenance plan is the best way to prevent breakdowns, reduce downtime, and maintain maximum performance during the months of highest demand. Checking the cooling system, using the right lubricants, and periodically monitoring the most sensitive components will extend the machine's lifespan and optimize operating costs.

 

If you need spare parts, components, or advice to keep your excavator in top condition during the summer, CYCLICA provides a wide catalog of machinery, engines, and spare parts for heavy machinery, along with a specialized technical team that will help you find the best solution for each piece of equipment.

FAQS

Why is it so important to perform specific maintenance in summer?

High temperatures accelerate the wear of mechanical and hydraulic components, increase the risk of overheating, and can reduce excavator performance. Preventive maintenance helps minimize these problems and avoids costly breakdowns.

 

What should I check before summer arrives? I

t is recommended to check the cooling system, clean radiators, check coolant level and condition, inspect hoses, verify thermostat operation, and check hydraulic oil status, filters, and the cabin air conditioning system.

 

How often should I clean the radiators in summer?

Under normal conditions, cleaning is recommended at least every two weeks. If the excavator works in highly dusty environments, such as quarries or demolitions, it is advisable to do it weekly to maintain proper cooling.

 

How does heat affect an excavator's hydraulic system?

High temperatures reduce hydraulic oil viscosity, decrease its lubricating capacity, and can cause greater wear on pumps, valves, and cylinders. Regular monitoring of the oil and its temperature is essential to prevent breakdowns.

 

What lubricants are most suitable for working in hot climates?

Oils and greases with synthetic or semi-synthetic formulations offer greater thermal stability and better maintain their properties when machinery works intensively under high temperatures.

 

Is it necessary to check tracks and tires during the summer?

Yes. Heat causes track chains to expand and increases internal tire pressure. Regularly checking tension and pressure helps reduce wear and prevents damage to the undercarriage.

 

How can I prevent engine overheating?

By keeping the cooling system clean, using the manufacturer-recommended coolant, checking proper fan operation, and preventing the radiator from accumulating dust or debris that hinders heat dissipation.

 

Where can I find spare parts and components for excavator maintenance?

At CYCLICA, you will find a wide catalog of spare parts, engines, and components for heavy machinery, as well as specialized advice to keep your excavator ready to work safely and efficiently throughout the summer.