The vacuum truck plays a central role in our society. It takes care of the muck and dirt in sewers that would otherwise cause a nasty overflow during a storm. While this equipment is highly capable of taking care of almost any kind of material, whether it is partially liquid, completely solid or even toxic, it does require strict maintenance routines. One of the most crucial parts of the vacuum truck that requires regular maintenance is its hydraulic system.

This mechanical component has a very important function. It is a vital powerhouse that controls most of the moving components of the truck. It is responsible for moving the boom for the suction house into position; it also operates the locking mechanism that secures the massive trap door. Due to the fact that vacuum trucks deal with liquid and sometimes caustic substances that could potentially damage components, it is important to perform regular maintenance on certain parts to prevent damage such as corrosion from occurring.

Common Causes of Hydraulic Failure

There are two common causes of hydraulic failure. One cause is a mechanical failure, or a malfunction that is caused by a component of the truck. The other most common cause is hydraulic fluid contamination. This contamination occurs when foreign material is present inside the fluid. Ideally, the inside of this system should be free from any type of contaminant except for the fluid. This is one place where the lack of regular maintenance could cause infiltration of the hydraulic system.

Although this system is sealed, prolonged use will eventually wear out the dust sealants that offer protection. An improperly sealed reservoir can also lead to severe contamination. Even without the presence of foreign debris, the deterioration of the fluid from prolonged use can lead to problems in its performance.

The presence of even the smallest foreign material inside this system could cause a myriad of problems such as: pump wear; malfunctioning of pumps or valves; and sludge accumulation.

Maintenance Tips

To prevent problems with the vacuum truck’s hydraulic system, it is important for operators to perform regular preventive maintenance at least twice a year or as prescribed by the manufacturer. The maintenance should include the following steps:

• Filter Replacement – In the case where foreign debris is present that could cause blockage to the small orifices along the system, the filter would prevent the debris from circulating inside the system. Regular filter replacement is the only way to ensure sufficient protection from any contaminants.

• Fluid Testing – As part of preventive maintenance, it is also important to conduct regular inspection of the quality of the hydraulic fluid. Such a test would detect the presence of contaminants that could potentially damage the system. A small amount of fluid should be drained after the system’s operation to be submitted for a particle count, as well as for testing for spectro-chemicals, water content, and viscosity.

• Flushing - As part of the vacuum truck’s regular maintenance schedule, it is also necessary to conduct regular flushing. This action involves cleaning the hydraulic system by draining the old fluid and replacing it with fresh fluid. This will ensure that any possible contaminants in the fluid or surrounding components are flushed away.

• Visual Inspection - It is also important to visually check the components on a regular basis for problems such as leaks around the fittings. Small leaks may lead to rupture during operation or cause the fluid to bleed out below the normal level, either of which could result in an unsafe operation of the truck’s hydraulic components.

These simple yet important tips apply to any piece of equipment that contains a hydraulic system. Following and implementing these tips can significantly increase the lifespan of this special element of a vacuum truck and ensure optimal performance throughout the life of the equipment!