A Breakdown of Heavy Equipment Filters Used in Construction Machinery

Filters are essential in construction equipment, crucial in maintaining optimal performance and extending the life of various machines. They help reduce maintenance costs, prevent unexpected breakdowns and extend the overall service life of equipment by keeping various systems clean and free of contaminants. Regular inspection and filter replacement are vital maintenance tasks that can significantly affect the productivity and reliability of construction equipment.

This article will discuss the types of filters found in construction equipment, offer best practices for replacement and explain how they keep equipment running smoothly.

How Do Filters Keep Construction Equipment Running Efficiently?

Filters protect vital systems in construction equipment by trapping contaminants such as dirt, dust, water and metal particles. If allowed to circulate, these contaminants can cause abrasive wear and damage to engine components, hydraulic systems and fuel delivery mechanisms. Air filters prevent debris from entering combustion chambers, enhancing engine efficiency. Fuel filters protect fuel injectors from clogging, while oil filters keep engine oil free from particles that can cause friction and wear. Hydraulic filters maintain fluid purity to prevent damage to pumps and valves.

Maintaining clean filters minimizes the risk of unplanned maintenance by ensuring consistent system performance and preventing blockages or contamination-related damage. This proactive approach reduces downtime and repair costs, allowing machines to operate reliably and efficiently over a more extended period. Routine filter checks and replacements are essential in achieving these benefits. 

Types of Filters Used in Heavy Equipment 

Air Filters

• Primary Function: Air filters trap dust, dirt and debris from the air before it enters the engine, preventing contaminants from causing wear and damage to internal components, thus ensuring optimal engine performance.
• Types of Machines: Excavators, loaders, bulldozers and cranes.
• Replacement Frequency: Typically, you should replace your machine’s air filter every 250 to 500 operating hours, depending on the environment and the manufacturer's specifications.
• Physical Appearance: Air filters generally appear as rectangular or cylindrical elements, often made of pleated paper, foam or cotton. They are housed within a plastic or metal casing to fit snugly into an engine's intake system. The pleats in the material increase the surface area for trapping dust and debris.
• Watch Out For: Air filters that are dirty or have discolored filter material typically indicate that a filter isn’t new. Clogged pleats can also restrict airflow through the filter causing performance issues. Conversely, tears or holes in the material will allow air to pass through unfiltered and let harmful contaminants into your engine. Lastly, be on the look out for compressed or misshapen air filters that do not properly fit into housings and allow unfiltered air to enter the engine.

Fuel Filters

• Primary Function: Fuel filters remove particles and contaminants from fuel before it reaches the engine, protecting fuel injectors and ensuring clean fuel flow, which supports efficient combustion and engine longevity.
• Types of Machines: Diesel-powered equipment like bulldozers, excavators, loaders and trucks.
• Replacement Frequency: Fuel filters should be replaced every 500 operating hours, as clean fuel is vital for engine efficiency.
• Physical Appearance: Fuel filters are typically cylindrical and often encased in metal or plastic. Inside, they contain a pleated filter medium made of paper or fabric designed to trap contaminants like dirt from the fuel. They are usually positioned along the fuel line and can vary in size depending on the machine.
• Watch Out For: Cracks or physical damage on the filter compromise the integrity of the filter and can leak fuel. Rust or other excessive debris accumulation can also indicate that a filter has been in storage too long and no longer structurally sound. If there’s visible moisture or water in the casing, it’s likely the filter is compromised.

Oil Filters

• Primary Function: Oil filters capture impurities and debris from engine oil, helping to maintain lubrication, reduce friction and prevent premature engine wear, keeping the engine running smoothly and reliably.
• Types of Machines: All heavy equipment with engines, including loaders, excavators and skid steers.
• Replacement Frequency: You should replace your machine’s oil filter every 250-500 operating hours, or at least once a year to maintain proper lubrication. It’s usually a good idea to replace your machine’s oil filter when you change the machine’s oil.
• Physical Appearance: Oil filters commonly look like metal canisters with a threaded end that screws onto the engine block. Inside, they have a filter medium—usually made of paper or fabric—wrapped around a central support tube. Oil filters may also have bypass and anti-drain-back valves to maintain oil flow under various conditions.
• Watch Out For: Corrosion or rusting on the casing can be indicative of a filter that’s been exposed to the elements to the point of compromising its integrity. Keep an eye out for degradation of seals—which can prevent the filter from being properly housed. Lastly, any bulging or misshapen indentions in the casing can indicate the filter is compromised.

Hydraulic Filters

• Primary Function: Hydraulic filters clean the hydraulic fluid by trapping particles and contaminants, which protects pumps, valves and other hydraulic components, reducing the risk of costly breakdowns and ensuring efficient operation.
• Types of Machines: Excavators, backhoes, forklifts and any machine with hydraulic systems.
• Replacement Frequency: To ensure hydraulic system cleanliness and performance, you should replace your hydraulic filter every 500-1000 operating hours. Some machines may require more frequent replacement, however, such as every 250 operating hours.
• Physical Appearance: Hydraulic filters can come in various shapes, including cylindrical or disc-like designs, and are encased in metal or robust plastic housings. They contain a filtration medium, often made of microscopic fibers or a mesh screen, designed to remove particles from hydraulic fluid.
• Watch Out For: Old or brittle seals and gaskets can prevent the filter from being tightly sealed. Any visible damage or deformation is usually a good indicator that the filter has been structurally compromised. Once the filter is installed, watch out for fluid leaks around the housing which can indicate a bad or incorrectly installed filter.

Cabin Air Filters

• Primary Function: Cabin air filters remove dust, pollen and pollutants from the air entering the operator cabin, creating a healthier environment for operators and preventing debris from affecting sensitive electronics.
• Types of Machines: Equipment with enclosed cabs, such as excavators and wheel loaders.
• Replacement Frequency: Cabin air filters should usually be replaced every 1,000 to 2,000 operating hours, or once a year, to maintain air quality within the cabin.
• Physical Appearance: Cabin air filters are typically flat and rectangular, resembling a large, dense white sponge. They are encased in a plastic frame and contain pleated filter media, often made of paper or a fibrous material. These filters are typically inserted into the machine's HVAC system to purify the air entering the cabin.
• Watch Out For: Visible mold or mildew indicate that moisture is trapped in the filter, compromising the air quality. As with all air filters, blocked pleats or tears in the filter material will either restrict air access or allow excess debris to pass through. Excessive dust and dirt on the filter itself are often indicators that your filter is not new and should be replaced.

Transmission Filters

• Primary Function: Transmission filters capture particles and contaminants from transmission fluid, which protects gears and clutches from excessive wear, supporting smooth gear shifts and prolonging transmission life.
• Types of Machines: Bulldozers, excavators, wheel loaders and backhoes require transmission filters.
• Replacement Frequency: You should replace your machine’s transmission filter every 1000 operating hours or sooner, depending on the type of transmission, operating conditions and the quality of the filter.
• Physical Appearance: Transmission filters come in various designs and materials. However, they typically resemble cylindrical components with a metal or plastic body containing a fine mesh or paper filter element that traps dirt and contaminants.
• Watch Out For: Like most other filters, deteriorated seals and gaskets are signs that the filter isn’t usable. Filters should be discarded if any physical damage to the filter has compromised its integrity. Once installed, watch out for signs of moisture or water contamination, fluid pressure issues or fluid leaks.  

Extending the Lifespan of Construction Equipment with Filters

Signs that a heavy equipment filter needs to be replaced include a noticeable loss of engine power, the equipment emitting black smoke or increased fuel consumption. A physical inspection of the filter itself may reveal excessive dirt and debris build-up, indicating that it is clogged and requires replacement. 

One best practice is to ensure regular inspection and cleaning of the filters to prevent excessive wear and tear. Using high-quality OEM or aftermarket filters designed for the equipment can also significantly improve longevity. 

Finally, maintaining a log of filter check-ups and replacements helps prevent potential issues from becoming significant problems. Regular maintenance checks are crucial to identify these signs early and ensure your equipment runs efficiently.

Saving Money on Filters

A lot of quality aftermarket filters on the market are made to the same standards as OEM products and make great alternatives to your machine’s manufacturer’s parts. Aftermarket filters are a good alternative for a reliable, cost-effective replacement to your OEM filter.  If your machine is still under warranty, however, you should consult with the manufacturer before using aftermarket parts to make sure you don’t void your machine’s warranty. 

Final Thoughts on Heavy Equipment Filters

It is crucial to regularly inspect and replace the filters in your heavy equipment to ensure optimal performance. Consistently maintaining these components helps prevent the buildup of debris and contaminants, which can lead to costly repairs down the road.

If you’re in need of replacement filters for your fleet, check out the EquipmentShare Shop. Our growing catalog of high-quality OEM and aftermarket filters has you covered. Plus, our collection of service kits for 250, 500 and 1000 hour maintenance can help ease the pain of tracking down parts. Still don’t see what you’re looking for? Reach out to our dedicated parts experts and get personalized assistance.