Choosing the best used air compressor requires you to observe and test a few key functions of the machine, including the motor, electrical wiring, and exterior hosing. Previous compressor owners may have cared for the compressor correctly, but some people can be neglectful of maintenance schedules. As a result, a used air compressor can have hidden issues that may affect the overall machine functionality.
An air compressor pressurizes incoming air for powering air tools, from drills to impact wrenches. Over time, a used air compressor may receive dents or small damage across its exterior surfaces from all the work it is used to perform. You can easily view the compressor's exterior and note any extreme damage, such as cracks. Small dents along the compressor's tank do not typically affect the machine's functionality; however, a small rupture along the surface will hinder air pressurization.
The compressor's motor is the heart of the system; it pulls air from the outside and compacts it into the attached tank. During the initial review of the used air compressor, you can turn the motor on and listen to its functions. Any odd frictional noise, such as scraping, should be noted as a possible problem. Additionally, you should listen to the noise level; oiled compressors should be much quieter than oil free machine types.
If the used air compressor is an oiled model, you should check the oil level by visually observing the gauge. A low oil level may indicate that the machine has been previously neglected and may be prone to breakdowns in the future. In addition, you can observe the oil's consistency. The oil should be clear of contaminants, as well as having a fluid motion within the machine. Used air compressor machines that do not receive periodic oil changes will have a chunky oil consistency that may impede the motor's physical movement.
You should carefully examine the exterior electrical wiring that connects the used air compressor to the wall outlet or electrical panel. The cable should be free of cracks and the connection to the electrical power should have no loose wiring. If you observe any loose wires on the cable, you should not touch it to prevent any accidental shock.
The hosing transports the pressurized air from the compressor's tank to the attached tool requiring power. You should examine this hosing along its length to verify that no holes exist. Any holes, or other damage, will allow air to escape; this escaped air will reduce the compressor's power output for the attached tool.