Changing Compressor Oil

Lubricated reciprocating air compressors, like an automobile, require regular oil changes to ensure that bearings and piston skirts are receiving clean lubricant to prevent metal to metal contact. Most small reciprocating compressor manufacturers recommend oil changes every 12 months or 500 hours – whichever comes first. Many small reciprocating air compressors may operate on single phase power directly fed by a breaker. Three phase models may use an economically priced off-the-shelf magnetic motor starter. In both of these scenarios, there is usually no provision made to log hours on the compressor.

The Problem with Start/Stop Air Compressors
The problem with compressors operating on a start/stop basis, is that the user usually has no idea of the actual hours that accumulate on the air compressor. As a result, oil changes are often neglected, or allowed to run past the due date. This may result in excessive wear causing reduced life expectancy of the pump, or pump failure if allowed to extend too long.

Two Solutions for Problematic Operation
Two easy solutions exist to ensure your compressor operates without problems rappl air compressors meterelating to oil changes.

  1. Always use the manufacturer’s recommended oil type and viscosity (temperature dependent). Never use a standard automotive detergent-added oil. This oil will quickly leave carbon deposits on compressor valves, and result in major repair issues.
  2. Know when to change your oil by installing an APPL vibration-activated hour meter. This is the least expensive way to KNOW the operating hours on your air compressor. It is also the easiest hour meter to install, as there is no electrical wiring required to power up the meter. It is powered by an on-board lithium battery rated for 8 year service life.

The Economical Hour Meter

How to Install The APPL Vibration-activated Hour Meter


  • To install, simply clean an area on the compressor air receiver saddle, and apply the Velcro adhesive backed strip (included)
  • Snip the startup wires on the back of the meter, and stick  it onto the Velcro backing.
  • The vibration from the compressor operation will cause the meter to time during compressor operation.
  • The numbers in the display will flash to indicate the unit is timing during compressor operation.

By logging your hours, you can also determine your compressor’s duty cycle over time, which may indicate changes in performance or demand for air.

These meters may also be used on other pumps, blowers, or anything that vibrates during operation. This is a super investment for only $49.00 each.